**4. Species Accounts**

## **Genus** *Centrolene* Jiménez de la Espada, 1872 [83]

**Etymology:** The name *Centrolene* is derived from the Greek words *kéntron* (point or spur) and *ol¯ éne¯* (elbow, forearm), alluding to the humeral spine found in males of this genus [84]. Although the name *Centrolene* has been used as neuter in gender for almost 150 years, now, because of an intricate game of words and nomenclatural regulations, it is considered to be feminine [85], creating nomenclatural instability that, in our opinion, was unnecessary. *Centrolene* is the type genus for the family Centrolenidae.

*Centrolene ballux* (Duellman and Burrowes 1989 [86]; Figures 20–23)

*Centrolenella ballux* Duellman and Burrowes, 1989 [86]. Holotype: KU 164725.

Type locality: "14 km (by road) west of Chiriboga (00◦18- S, 78◦49- W), 1960 m, Provincia de

Pichincha, Ecuador" (now in Provincia de Santo Domingo de los Tsáchilas).

*Centrolene ballux*—Ruiz-Carranza and Lynch, 1991 [6].

*"Centrolene" ballux*—Guayasamin, Castroviejo-Fisher, Trueb, Ayarzagüena, Rada, and Vilà, 2009 [1].

**Common names:** English: Gold-dust Glassfrog. Spanish: Rana de Cristal Polvo de Oro.

**Etymology:** The specific name *ballux* is Latin; it means "gold dust" and is used in reference to the minute gold flecks on the dorsum [86].

**Identification:** On the Pacific versant of the Ecuadorian Andes, only *Nymphargus buenaventura* and some populations of *N*. *gri*ffi*thsi* are similar to *Centrolene ballux* in having a green dorsum with small light spots (Figure 20), but they di ffer by possessing basal webbing between outer fingers (moderate webbing in *C*. *ballux*), concealed prepollex (distinct in *C*. *ballux*), and lacking humeral spines (present in males of *C*. *ballux*). The Colombian *"Centrolene" robledoi* resembles *C*. *ballux;* both lack vomerine teeth, have a small series of white spots on flanks, and have a similar webbing and snout shape. However, *C*. *robledoi* has small dark spots on its dorsum (absent in *C*. *ballux*), concealed prepollex (distinct in *C*. *ballux*), and is slightly larger than *C*. *ballux* (males, SVL 19.9–24.4 mm in *C*. *robledoi;* 19.2–22.2 mm in *C*. *ballux*). *Centrolene peristicta* and *C*. *lynchi* are sympatric with *C*. *ballux* in several localities, but the two species can be distinguished by having dorsal dark and light minute spots (only light spots present in *C*. *ballux;* Figure 20).

**Diagnosis:** (1) Vomers lacking teeth; (2) snout bluntly rounded to truncated in dorsal and lateral profiles (Figure 21); (3) tympanum oriented almost vertically, ED/TD = 31%–34%; tympanic annulus visible except for dorsal border covered by supratympanic fold; tympanic membrane partially pigmented, di fferentiated from surrounding skin; (4) dorsal surfaces shagreen with small warts; (5) pair of enlarged subcloacal tubercles (Figure 15); (6) anterior two-thirds of ventral parietal peritoneum white, posterior third transparent (condition P3); silvery white pericardium; no iridophores in peritonea covering intestines, stomach, testes, kidneys, gall bladder, and urinary bladder (condition V1); (7) liver tetralobed, lacking iridophores (condition H0); (8) humeral spines present in adult males; (9) no webbing between Fingers I and II, webbing between Fingers II and III basal or absent; webbing formula for outer fingers: III (2<sup>1</sup>/4–23/4)—(2–2+) IV (Figure 21C); (10) webbing formula on foot: I 1—(2–2+) II 1—(2–2+) III (1–1+)—(2–2<sup>1</sup>/3) IV 21/2—(1–11/3) V; (11) ulnar fold low, white; inner tarsal fold

low; outer tarsal fold absent, but small white tubercles evident along ventrolateral margin of tarsus; (12) distinct prepollex, clearly separated from Finger I; in males, nuptial pad Type I; (13) Finger II slightly longer than Finger I (Finger I 91.4%–98.0% of Finger II); (14) disc of Finger III of moderate size, about 47.4%–59.3% of eye diameter; (15) in life, dorsum green with small white warts; upper lip white; bones green; (16) in preservative, dorsal surfaces lavender with small white and/or unpigmented spots, particularly evident on limbs; (17) iris whitish cream with dark-grey thin reticulation and pale yellow hue around pupil; (18) melanophores mostly absent from fingers and toes, except for a few on Toes IV and V and on base of Finger IV; (19) males call from the upper side of leaves; call emitted sporadically and consisting of a single short note (328.5–420.4 ms) with 7–9 pulses; mean dominant frequency at peak amplitude 4833 Hz ± 14 (range 444–464); notes are frequency modulated (Márquez et al. 1996); (20) fighting behavior unknown; (21) eggs deposited on the upper sides of leaves; short-term maternal care unknown; long-term parental care absent; (22) tadpoles undescribed; (23) minute body size; SVL 19.2–22.2 mm (X = 20.6 ± 0.911, *n* = 25) in males; SVL 21.0–23.3 mm (*n* = 3) in females.

**Figure 20.** *Centrolene ballux* in life from Reserva Las Gralarias, Pichincha province, Ecuador. (**A**,**B**) Adult males. (**C**) Adult male in dorsal view, QCAZ 40199. (**D**) Egg clutch on upper side of leaf. (**E**) Metamorph. (**F**) Adult female in ventral view, QCAZ 40196. Photos by Carl R. Hutter (**B**,**D**,**E**), Luis A. Coloma (**C**,**F**), and Alejandro Arteaga/Tropical Herping (**A**).

**Figure 21.** *Centrolene ballux*. (**A**) Head in lateral view, KU 164725. (**B**) Finger I and nuptial pad in dorsal view, KU 200275, adult male. (**C**) Hand in ventral view, KU 164725. Illustrations by Juan M. Guayasamin.

**Color in life** (Figure 20): Dorsum lime green with small greenish–white to yellowish–white warts; fingers and toes yellowish green; anterior two-thirds of ventral parietal peritoneum white; visceral peritoneum lacking iridophores; pericardium silvery white; bones green; upper lip yellowish white to white; iris cream white with fine black reticulations.

**Color in ethanol:** Dorsal surfaces of head, body, and limbs lavender with small white and/or unpigmented warts; hands and Toes I–III mostly unpigmented; margin of upper lip white; ulnar fold white; small tubercles on outer ventrolateral margin of tarsus white; small white tubercles posterior to cloacal opening; ventral surfaces cream. Anterior two-thirds of the ventral parietal peritoneum white, posterior third transparent; silvery white pericardium; no iridophores in peritonea covering intestines, stomach, testes, kidneys, gall bladder, and urinary bladder.

**Biology and ecology:** Individuals are active at night on the upper surfaces of leaves of bushes and trees 50–800 cm above and along small streams, or on ferns over roadside ditches (Arteaga et al. 2013). The reproductive activity of *Centrolene ballux* occurs in the rainy season (December–April [87]). One male (IND-AN 1725) was on a leaf 5 cm below another leaf on which there was a clutch of 18 eggs [86]. Another clutch found at La Planada had 13 eggs. Near Chiriboga, a gravid female (KU 164729) with green eggs and five adult males were found along a stream on 8 May 1975. At Reserva Las Gralarias, on March 2009, a clutch with 21 embryos was found on the upper side of a leaf, which was hidden by another leaf; an adult male was observed nearby (ca. 100 cm from the clutch). *Centrolene ballux* is relatively abundant at Reserva Las Gralarias, where it maintains reproductive populations along several streams (Ballux Creek, Five-frog Creek, Heloderma Creek, Chalguayacu River, Kathy's Creek; [88]). It is unknown if females provide short-term parental care to egg clutches; males do not exhibit parental care [25].

**Call** (Figure 22): The advertisement call of *Centrolene ballux* was described from Las Palmeras, Ecuador, by Márquez et al. [89]. The call was emitted sporadically and consisted of a single short note (328.5–420.4 ms, *n* = 2) with 7–9 pulses, the first 4–5 being repeated at short, regular intervals, and the last three pulses being emitted at longer intervals (mean pulses per second = 21.0 ± 0.1, range 21.3–21.4). The dominant frequency was high (mean dominant frequency at peak amplitude 4833 Hz ± 14). The notes were frequency modulated (dominant frequency at the beginning of note is lower than at its end). Recordings obtained at Reserva Las Gralarias, Ecuador, match this description.

**Figure 22.** Call of *Centrolene ballux* from Reserva Las Gralarias, Pichincha province, Ecuador.

**Tadpole:** Not described.

**Distribution** (Figure 23): *Centrolene ballux* is known from six localities in the cloud forests of Carchi, Imbabura, Pichincha, and Santo Domingo de los Tsáchilas provinces (Ecuador) and one in the department of Nariño (Colombia) on the Pacific slopes of the Cordillera Occidental of the Andes at elevation between 1780 and 2340 m [86,87,89] (Specimens Examined). The species inhabits the Western Montane Forest ecoregion. In Ecuador, it has a potential distribution of 4752 km2.

**Conservation status:** Globally, *Centrolene ballux* is currently listed as *Endangered* by the IUCN [90]. In Ecuador, the most recent records of the species are from Reserva Las Gralarias (March 2018) and Reserva Río Manduriacu (2008) [21]. In Colombia, the last published record is from Reserva La Planada on April–June 1986 [86]. Recent surveys at Quebrada Zapadores and Las Palmeras (= Río Guajalito) have been unsuccessful in finding this species [91] (DFCH unpubl. data). During the rainy seasons (December–April) of 2011–2018, reproductive populations were observed in four streams at Reserva Las Gralarias. The species has a very restricted distribution, with only five known localities in Ecuador, in an area where forest fragmentation is common. At Reserva Las Gralarias, the amphibian chytrid fungus *Batrachochytrium dendrobatidis* infects *C*. *ballux* with a relatively high prevalence, but no recent declines have been recorded [92].

**Evolutionary relationships** (Figure 24): *Centrolene ballux* and *C*. *buckleyi* are sister species.

**Specimens examined:** *Centrolene ballux:* Ecuador: *Provincia de Carchi:* ca. 5 km W La Gruel (0.916667 N, 78.13333 W; 2340 m), KU 202798. *Provincia de Pichincha:* Reserva Las Gralarias (0.00806 S, 78.72433 W, 1852 m), QCAZ 40195–99; Quebrada Zapadores, 5 km ESE of Chiriboga on Chiriboga–Quito road (0.245278 S, 78.7261 W, 2010 m), KU 164733. *Provincia de Santo Domingo de los Tsáchilas:* 14 km we'st of Chiriboga on Chiriboga–Santo Domingo road (0.265278 S, 78.8478 W, 1960 m), KU 164725 (holotype), 164726–32 (paratypes).

**Localities from the Literature:** *Provincia de Pichincha:* Las Palmeras (=Bosque Protector Río Guajalito) (0.283 S, 78.75 W; 1800 m) [89].

**Figure 23.** Distribution of *Centrolene ballux* in Ecuador (yellow dots).

**Figure 24.** Evolutionary relationships among species in the genus *Centrolene*, inferred using maximum likelihood and Bayesian criteria.

## *Centrolene buckleyi* (Boulenger 1882 [93]; Figures 25–28)

*Hylella buckleyi* Boulenger, 1882 [93]. Syntypes: BM 78.1.25.16 (Intac), 80.12.5.201 (Pallatanga). See comments below on type material. Neotype: KU 202770.

Neotype locality: Isla Wolf of Laguna Cuicocha (0◦18-07" N, 78◦22-00" W; 3070 m), Provincia Imbabura, Ecuador, collected on 28 February 1984 by W. E. Duellman.

*Centrolenella buckleyi*—Noble, 1920 [94].

*Cochranella buckleyi*—Taylor, 1951 [15]. Rivero, 1961.

*Centrolenella buckleyi buckleyi*—Rivero, 1968 [95].

*Centrolenella johnelsi* Cochran and Goin, 1970 [96]. Holotype: MLS 432. Type locality: "San Pedro, N of Medellín, Antioquia, Colombia". Synonymy by Ruiz-Carranza and Lynch, 1991 [6].

*Centrolene buckleyi*—Ruiz-Carranza and Lynch, 1991 [6].

**Common names:** English: Buckley's Glassfrog. Spanish: Rana de Cristal de Buckley.

**Etymology:** The specific name *buckleyi* was used to recognize Mr. Buckley, who collected the type series of the species.

**Identification:** *Centrolene buckleyi* is one of the few species of glassfrogs found in the highlands of Ecuador (2050–3070 m). It is easily recognized by the presence of a large humeral spine (in adult males), white upper lip, inclined snout in lateral profile, and reduced webbing between fingers (Figures 25 and 26). In life, dorsal surfaces are uniform green, but some individuals have small whitish warts. *Centrolene heloderma* and *C*. *condor* can be confused with *C*. *buckleyi;* however, *C*. *heloderma* has a pustular dorsal skin (shagreen in *C*. *buckleyi*) and *C*. *condor* has small light and dark spots on the dorsum (dark spots absent in *C*. *buckleyi*). Similar species from other countries include *Centrolene hesperia*, *C*. *lemniscata* (Peru), *C*. *altitudinalis*, and *C*. *venezuelensis* (Venezuela). We note that, as currently defined, *C*. *buckleyi* is a species complex that requires further taxonomic studies.

**Figure 25.** *Centrolene buckleyi* in life. (**Left**): Adult male from locality near Oyacachi, Napo province, 3012 m, MZUTI 763, photo by Eduardo Toral. (**Right**): Adult male from Guarumales, Zamora Chinchipe province, 2070 m, CJ-11364, photo by Diego Acosta-López.

**Comments on type material:** The description of *Centrolene buckleyi* was based on two specimens housed at The Natural History Museum, London (formerly British Museum of Natural History). As noted by Goin [97] and Lynch and Duellman [22], one syntype (BMNH 80.12.5.201; from Pallatanga, Provincia de Chimborazo, Ecuador) is now almost completely macerated in ethanol and almost no bones remain, and the other (BMNH 78.1.25.16; from Intac, Imbabura province, Ecuador) is missing and recent searches by Jeff Streicher and DFCH were unsuccessful. Both localities are on the western versant of the Andes of Ecuador, on the slopes of the Cordillera Occidental. Because *Centrolene buckleyi* represents a species complex [20,98] (Figure 24), we here designate a neotype for *Centrolene buckleyi* (KU 202770, adult female) collected from Laguna de Cuicocha (near the syntype locality of Intac = Intag), thereby allowing clear comparisons among populations that might represent independent lineages. The morphological characteristics of the neotype fully correspond to those mentioned by Boulenger [93] in the original description of the species. Additionally, mitochondrial sequences of the neotype are included in the phylogeny shown in Figure 24. The designation of the neotype is justified on the Article 75.3 of the International Code of Zoological Nomenclature [99].

**Diagnosis:** (1) Vomers lacking teeth; (2) snout round in dorsal aspect, slightly sloping to sloping in lateral profile (Figure 26); (3) tympanum partially or completely hidden under skin, when visible oriented almost vertically, its diameter is 29.0%–38.6% of eye diameter; supratympanic fold moderately heavy; tympanic membrane slightly thinner than skin around tympanum; (4) dorsal skin finely shagreen, males with spicules; (5) pair of round subcloacal warts (Figure 26); (6) anterior half to two-thirds of venter covered by white parietal peritoneum, posterior portion translucent (condition P2–P3); silvery white pericardium; translucent peritoneum covering intestines, stomach, testes, kidneys, gall bladder, and urinary bladder (condition V1); (7) liver with four or five lobes, lacking iridophores (condition H0); (8) in males, humeral spines present; (9) webbing absent between Fingers I, II, and III; reduced webbing between outer fingers: III (2<sup>1</sup>/4–3−)—(2<sup>+</sup>–21/2) IV (Figure 26); (10) webbing formula on foot: I (1<sup>1</sup>/2–2−)—(2–2<sup>1</sup>/4) II (1−–1<sup>+</sup>)—(2<sup>+</sup>–21/2) III (1<sup>+</sup>–12/3)—(21/3–3) IV (2<sup>2</sup>/3–3)—(12/3–2−) V; (11) ulnar fold low, ventrolateral margin of arm white; inner tarsal fold evident; outer tarsal fold absent, external ventrolateral margin of tarsus white; (12) concealed prepollex; in males, nuptial pad Type I; (13) Finger II slightly longer than Finger I (Finger I 86.5%–98.7% of Finger II); (14) disc of Finger III of moderate size, about 54.2%–64.5% of eye diameter; (15) in life, dorsum uniform green that may have scattered whitish warts; upper lip white, usually continuing as a white line across the flanks; bones green; (16) in preservative, pericardium and anterior half to two-thirds of ventral parietal peritoneum white, visceral peritoneum translucent, peritoneum around kidneys translucent; (17) iris grey-white with thin black reticulation and a horizontal brown stripe; (18) melanophores mostly absent from fingers and toes, except for a few on Toes IV and V and on base of outer fingers; (19) males call from the upper sides of leaves; two call descriptions available (see Call section); (20) males fight upside down, grasping one another venter to venter; (21) eggs deposited on the upper sides of leaves; females provide short-term parental care; prolonged parental care is absent; (22) tadpoles unknown; egg clutches deposited within male's territory, but parental care has not been reported; (23) medium body size, SVL in males 26.5–30.9 mm ( X = 29.0; *n* = 25), in females 29.3–34.4 mm ( X = 31.2; *n* = 9).

**Figure 26.** *Centrolene buckleyi*. ( **A**) Head in lateral view, adult female, KU 178035. (**B**) Venter and thighs in ventral view, adult female, KU 178040. ( **C**) Hand in ventral view, adult female, KU 178055. Illustrations by Juan M. Guayasamin.

**Description of Neotype:** Adult female, SVL 32.6 mm (KU 202770; Figure 27). Head wider than long; head length 28.5% of SVL; snout rounded in dorsal profile, sloping in lateral profile; canthus indistinct; loreal region slightly concave; upper lip white, slightly flared; nostril protuberant, closer to eye than to tip of snout, directed dorsolaterally; internarinal area barely depressed. Eye small (diameter 14% of SVL), directed anterolaterally; transverse diameter of disc of Finger III 50.9% of eye diameter. Supratympanic fold conspicuous; tympanum not visible externally. Vomers lacking teeth, choanae large, round; tongue ovoid, ventral posterior half not attached to floor of mouth and posterior margin notched; vocal slits extending posterolaterally from the posterolateral base of tongue to angle of jaws.

Humeral spine absent; ulnar fold evident, white; relative length of fingers: III > IV > II > I; webbing between Fingers I, II, and III absent, basal webbing for outer fingers: III 22/3—2<sup>+</sup> IV; discs and disc pads expanded, elliptical; subarticular tubercles large, round, simple; numerous fleshy supernumerary tubercles present; palmar tubercle elliptical, simple. Length of tibia 51.5% of SVL; inner tarsal fold evident; outer tarsal fold absent, ventrolateral margin of tarsi white; feet about three-fourths webbed; webbing formula on foot I 11/2—2 II 1—2<sup>+</sup> III 11/2—3 IV 3—12/<sup>3</sup> V; discs on toes elliptical; disc on Toe IV narrower that disc on Finger IV; inner metatarsal tubercle large, ovoid; outer metatarsal tubercle not evident; subarticular tubercles small, round; numerous fleshy supernumerary tubercles evident.

Skin on dorsal surfaces of head, body, and lateral surface of head and flanks shagreen, lacking spicules; throat smooth; venter and lower flanks areolate; cloacal opening directed posteriorly at upper level of thighs; small, white tubercles located immediately posterior to cloacae. In ventral view, pair of enlarged subcloacal tubercles not evident.

**Figure 27.** *Centrolene buckleyi*, adult female, neotype, KU 220770. Ecuador, Imbabura province, Isla Grande, Lago Cuicocha, 3070 m. Photos by Juan M. Guayasamin.

**Color in life** (Figure 25): Dorsal surfaces bright to dark green, sharply demarcated laterally from lower white flanks; throat and most of venter pale green; parietal peritoneum yellowish white; edge of upper lip white; ventrolateral borders of arms and tarsus white; small, white warts posterior to cloacal opening; bones green; grey–white iris with thin black reticulation and a horizontal brown stripe. Some individuals have whitish warts on dorsum (QCAZ 22388, 26031–32) or small white spots on legs and forearms (KU 202770)

**Color in ethanol** (Figure 27): Dorsum of head and body uniform lavender or with minute whitish or unpigmented spots; limbs cream with slight lavender tone and with or without small white spots; conspicuous white border on the upper lip; dorsally, all fingers, Toes I–III, and most of Toe IV unpigmented; ventrolateral borders of arms and tarsus white; cloacal region mostly unpigmented, except for several white warts posterior to cloacal opening; males with cream nuptial pad on Finger I. Three specimens (QCAZ 26031–32, KU 178042) were dissected to observe coloration of internal organs: Anterior half to two-thirds of ventral parietal peritoneum white; pericardium white; hepatic peritoneum transparent; peritonea covering viscera and kidneys translucent to opaque.

**Biology and ecology:** During the day, *Centrolene buckleyi* has been found in terrestrial and arboreal bromeliads near and away from streams in secondary forest and pastures (J. D. Lynch, W. E. Duellman field notes). During the night, *Centrolene buckleyi* were active on terrestrial bromeliads and vegetation 30–160 cm above streams, lakes, and marshes in primary and secondary forests ([20,22], this work). Lynch and Duellman [22] suggested that *C*. *buckleyi* might breed in the same situations as other centrolenids—rapid, mountain streams—but also in bromeliads or in ciénegas; they based this statement on the observation of an egg clutch (KU 170221) on the inner leaf of bromeliad in an area where *C*. *buckleyi* was abundant. Males fight dangling upside down while holding onto vegetation with their hind limbs, grasping one another venter to venter (Bolívar et al. 1999). A male (QCAZ 22388) was found on the upper side of a leaf close to another leaf with a clutch of eggs, approximately 160 cm above a stream [20]. Females provide short-term parental care to egg clutches; males do not exhibit parental care [25].

**Call** (Figure 28): Two descriptions of the call of *Centrolene buckleyi* are available in the literature [20,100]. The di fferences between these calls, combined with the non-monophyly of *C*. *buckleyi* (Figure 24), clearly show that *Centrolene buckleyi*, as currently recognized, represents a species complex [20,98]. Below we describe a call from the highlands of Ecuador (MZUTI 763; see Examined Specimens); although the call presented herein is not from the neotype locality, genetically, it clusters together with samples from the type locality; thus, apparently corresponding to the same species. Calls are produced in series, every 45–67 s (mean = 53 ± 9.9; *n* = 10). Each call has a single, highly pulsed note, with a duration of 0.248–0.288 s (mean = 0.264 ± 13.7; *n* = 10; Figure 23). Calls have a slight frequency modulation, with an initial dominant frequency at 2816–2941 Hz (mean = 2893 ± 38; *n* = 10) and a final dominant frequency at 3222–3255 Hz (mean = 3229 ± 12; *n* = 10). First harmonics are at 5385–6393 Hz.

**Figure 28.** Call of *Centrolene buckleyi*, MZUTI 763. Recorded at páramo wetland nearby Oyacachi, 3012 m, Napo province, Ecuador.

**Tadpole:** Not described.

**Distribution** (Figure 29): The *Centrolene buckleyi* species complex occurs through the Andes of Colombia and Ecuador to Huacambamba in the Departamento de Piura in northern Peru at elevations between 2450 and 3300 m ([17,101,102], this work). Records below 2450 m are considered dubious. In Ecuador, *Centrolene buckleyi* is found along the Cordillera Oriental and Cordillera Occidental of the Andes, and inhabits the Western Montane Forest, Andean Shrub, Páramo, and Eastern Montane Forest ecoregions, with a potential distribution of 44,586 km2.

**Figure 29.** Distribution of the species complex currently recognized as *Centrolene buckleyi* in Ecuador (yellow dots).

**Conservation status:** *Centrolene buckleyi* is listed as *Vulnerable* at a global level by the IUCN [103]. In Ecuador, *Centrolene buckleyi* was abundant along the high Andes, but recent fieldwork demonstrates population crashes at historical localities (e.g., Pilaló, Cuicocha, Cashca Totoras, Quito, San Pablo de Atenas, Papallacta) ([91], JMG pers. obs.). The last records of the species in Ecuador are from Bosque Protector Cashca-Totoras in 2002 [91], Morán on February 2017 (Diego Batallas, pers. com., Mario Yánez-Muñoz, pers. com.); Yanayacu Biological Station in 2001–2003 [20], Sigchos (0◦42- S, 78◦53- W; 2080 m) on March 2008, Zamorahuaico, near Loja (3◦59- S, 79◦12- W; 2100 m) on August 2008, and nearby Oyacachi (3012 m) on May 2012. The habitat (Páramo, Andean shrub, and montane forest) occupied by the species is heavily impacted by human activities, mainly agriculture and pasture lands. Considering that that populations declines are widespread in the species complex, we sugges<sup>t</sup> the category of *Critically Endangered* in Ecuador (IUCN criteria A2c,e).

**Evolutionary relationships** (Figure 24): As defined herein, *Centrolene buckleyi* is sister to *Centrolene ballux*. See Taxonomic Remarks.

**Taxonomic Remarks:** *Centrolene buckleyi* is a species complex that requires formal subdivision [20,98]. Moreover, morphologically, *Centrolene buckleyi* is almost identical to four Andean species, namely *C*. *altitudinalis*, *C*. *venezuelensis* (Venezuela), *Centrolene hesperia*, and *C*. *lemniscata* (Peru). Myers and Donnelly [104] elevated the Venezuelan populations of *Centrolene buckleyi* (*Centrolenella buckleyi venezuelensis* Rivero, 1968 [105]) to the species status, without morphological justification; Señaris and Ayarzagüena [106] provided morphological and acoustic data supporting the recognition of *Centrolene venezuelensis*. The original descriptions of *C*. *hesperia* and *C*. *lemniscata*

did not include a comparison between these species and *C*. *buckleyi;* therefore, a reevaluation of their species status is necessary. Genetic [20,98] and morphological [105,106] differences support the validity of *Centrolene altitudinalis*; for example, the lower two-thirds of the tympanic annulus is visible in *C*. *altitudinalis*, whereas the tympanum is completely or mostly concealed in *C*. *buckleyi*, *C*. *lemniscata*, and *C*. *hesperia*. Also, we call attention to the conspicuous geographical barriers that have the potential of limiting gene flow among these species. The Peruvian *C*. *hesperia and C*. *lemniscata* are isolated from other species by the Huacambamba Depression, and isolated from each other by interandean valleys. Likewise, the Venezuelan *C*. *venezuelensis* and *C*. *altitudinalis* are isolated from other species by the Táchira Depression. The distribution of *C*. *buckleyi* is restricted, mostly, to the Andes of Ecuador and Colombia, but these populations, based on genetic and call data, represent several independent evolutionary lineages (Figure 24). Thus, clearly, further work is necessary within this species complex.

**Measurements of neotype (in mm):** The morphometric data for the neotype (female, KU 202770) are as follows: SVL = 32.6; tibia length = 16.8; foot length = 15.1; head length = 9.3; head width = 10.3; interorbital distance = 3.3; upper eyelid width = 2.6; internarial distance = 2.8; eye-nostril distance = 2.2; snout-eye distance = 4.3; eye diameter = 4.6; tympanum diameter = —; eye-tympanum distance = —; radio-ulna length = 6.72; hand length = 10.4; Finger I length = 6.3; Finger II length = 6.7; disc of Finger III = 2.3; and Finger III width = 1.2.

**Specimens examined:** *Centrolene buckleyi:* Ecuador: *Provincia del Azuay:* 10 km N Girón (3.0833 S, 79.0833 W; 2750 m), KU 202777; 11.5 km SE Gualaceo (2.9333 S, 78.71667; 2940 m); Sigsig (3.05 S, 78.8 W; 2450), QCAZ 1245. *Provincia de Bolívar:* Bosque Protector Cashca-Totoras (1.71 S, 78.98 W; 2800–3159 m), QCAZ 740, 21231; Guanujo (1.5667 S, 79.01667 W. 2600 m), KU 182214; San Pablo de Atenas (1.8 S, 79.0667 W), QCAZ 372, 2415–16; Santiago (1.7167 S, 78.9833 W), QCAZ 1531. *Provincia de Carchi:* near Tulcán (0.8 N, 77.7167 W; 2770 m), KU 118005–08; 14 km SW Tulcán (0.72889 N, 77.7958, 3340 m), KU 164516; 5.7 km NW El Carmelo (0.6908 N, 77.63389 W, 2910 m), KU 178053–67; Santa Bárbara (0.61667 N, 77.5833; 2650 m), KU 190017–19; El Goatal, Morán, 0.5 km from Escuela de Morán via La Cortadera, QCAZ 43110; Morán (0.7686 N, 78.056 W, 2785 m), DBR 187, 193. *Provincia de Cañar:* 4 km W Ingapirca (2.51667 S, 78.9 W; 3000 m), KU 178077. *Provincia de Cotopaxi:* near Pilaló (0.933 S, 78.9833 W; 2410 m), KU 178034–50, 202780–83. *Provincia de Imbabura:* La Delicia (0.0667 N, 78.7 W; 2710 m), KU 178079–81, 180311; Lago Cuicocha (0.3 N, 78.3667 W; 3010 m), KU 138822, 178030–33; S shore of Lago Cuicocha (0.29194 N, 78.35389; 3070 m), KU 202703–74; Isla Wolf in Lago Cuicocha (0.3019 N, 78.366 W; 3070 m), KU 202770–72; Mariano Acosta (0.3 N, 77.9833 W; 3000 m), QCAZ 12172. *Provincia de Loja:* 13 km E Loja, Abra de Zamora (3.9744 S, 79.1114 W; 2800 m), KU 164511–15, 166321; 2 km SSW Saraguro (3.6397 S, 79.24 W; 2560 m), KU 178068–76; 3.7 km S Saraguro (3.6469 S, 79.245 W; 2800 m), KU 202778–79. *Provincia de Morona Santiago:* 25.5 km WSW Plan de Milagro (3.21667 S, 78.5 W; 2600 m), KU 202775. *Provincia de Napo:* 9.2 km ESE Papallacta (0.3761 S, 78.0683 W; 2750 m), KU 178052; 11 km ESE Papallacta (0.3869 S, 78.0569; 2660 m), KU 164507–09; 11.2 km ESE Papallacta (0.388 S, 78.055; 2660 m), KU 178051; 12 km ESE Papallacta (0.39194 S, 78.04944 W; 2630 m), KU 155481–92, 164505–06; 31 km N Jondachi (0.5711 S, 77.869 W; 2190 m), QCAZ 2740; Oyacachi–El Chaco road (0.219 S, 78.044 N; 3012 m), MZUTI 763. *Provincia de Pichincha:* 9.5 km NW Nono (0.026389 S, 78.6403 W; 2530 m), KU 164510; Hacienda El Beaterio, KU 178078; near Machachi (0.5 S, 78.5667 W; 2950 m), KU 148429–30. *Provincia de Zamora Chinchipe:* 13.5 km E Loja (3.973 S, 79.107 W; 2800 m), KU 142648; Guarumales (3.9405 S, 78.987 W; 2070 m), CJ-11364.

**Localities from the literature:** *Centrolene buckleyi:* Ecuador: *Provincia del Azuay:* Sinicay, 2560 m, AMNH 17464. *Provincia de Chimborazo:* Pallatanga (1.9833 S, 78.95 W; 1520 m), BMNH 80.12.5.201. *Provincia de Imbabura:* Intac (0.4 N, 78.6 W), BMNH 78.1.25.16. *Provincia de Zamora Chinchipe:* Sabanilla (4.033 S, 79.0 W), AMNH 13530 [22,93].

*Centrolene charapita* Twomey, Delia, and Castroviejo-Fisher 2014 [19] (Figures 30 and 31).

*Centrolene charapita* Twomey, Delia, and Castroviejo-Fisher, 2014 [19]. Holotype: MHNCP 13933. Type locality: "near the village of La Oliva, past the village of Muyo (a larger village roughly 49 km N from Bagua), Amazonas, Peru (5◦18-3.86" S, 78◦23-44.57" W, 682 m)".

**Common names:** English: Charapita Glassfrog. Spanish: Rana de Cristal Charapita.

**Etymology:** The specific name *charapita* derives from a type of yellow chili pepper (ají charapita), which resembles the dorsal ocelli of the species [19].

**Identification:** *Centrolene charapita* is the only glassfrog with yellow dorsal ocelli, scalloped and enameled ulnar and tarsal folds (Figure 30), and relatively large size (adult male SVL = 34.7–37.0).

**Figure 30.** *Centrolene charapita* in life. Type series from near La Olivia, 682 m, Departamento Amazonas, Peru. Photos by Santiago Castroviejo-Fisher and Evan Twomey.

**Diagnosis:** *Centrolene charapita* is recognized by (modified from Twomey et al. [19]): (1) Vomers with 4–10 vomerine teeth; (2) in Peruvian population, snout truncated in dorsal view and truncated to slightly rounded in profile; in Ecuadorian population, snout round in dorsal view and sloping in profile; (3) tympanum small, partially hidden under skin; supratympanic fold present; (4) dorsal skin smooth with microspicules and low enameled warts on ocelli; venter and thighs coarsely areolate, other ventral surfaces smooth; (5) cloacal ornamentation conspicuous, formed by enameled folded skin (flaps) surrounded by lower warts; pair of enlarged subcloacal warts; (6) anterior third-to-half of parietal peritoneum white, posterior portion transparent (state P2); pericardium, hepatic, renal, and gonadal peritonea transparent, visceral peritoneum white; (7) liver trilobed, lacking iridophores (state H0); (8) humeral spines absent; (9) no webbing between Fingers I and II; webbing formula for outer fingers: II 2−—31/<sup>3</sup> III 2—(1<sup>+</sup>–11/3) IV; (10) webbing formula on foot: I (1<sup>1</sup>/3–11/2)—(2−–2) II 1—(2−–21/3) III (1–1+)—(2–2+) IV (2–2<sup>1</sup>/3)—1 V; (11) scalloped enameled ulnar and tarsal folds, extending from fringe on postaxial edge of Finger IV to elbow, and from fringe on postaxial edge of Toe V to ankle, respectively; (12) concealed prepollex; in males, nuptial pad Type I, not pigmented; (13) when appressed, Finger I about equal length or slightly longer than Finger II; (14) eye diameter about 2.5 times the width of disc on Finger III; (15) in life, dorsal and dorsolateral surfaces covered with yellow or pale green spots of di fferent size (ocelli); upper lip and tip of finger and toes I, II, and III white (enameled); ventral surfaces not pigmented; bones green; (16) in preservative, dorsal surfaces and dorsolateral surfaces with cream spots of di fferent size (ocelli), bearing enameled warts and microspicules set in a lavender-greyish reticulum; upper lip and tip of finger and toes I, II, and III white (enameled); ventral surfaces not pigmented; (17) iris in life o ff-white to light grey with yellow tones and black dots and reticulation, with black ring delimiting iris; in preservative, iris silvery white with black dots and reticulation, with black ring delimiting iris; (18) in life and preservative, tip of fingers and toes white (enameled), Finger IV and Toes IV and V pigmented, Finger II and Toe III not pigmented, but for a small group of melanophores towards the tip, Fingers and Toes I and II not pigmented; (19) males call from upper side of leaves; call not described; (20) fighting behavior unknown; (21) eggs deposition site unknown; parental care unknown; (22) tadpoles undescribed; (23) large size in adult males; SVL 34.7–37.0 mm (*n* = 5) in males; females unknown.

**Color in life** (Figure 30): Modified from Twomey et al. [19]. Dorsal and dorsolateral surfaces green, with yellow or pale green spots of di fferent size (ocelli). Upper lip and discs of fingers and toes I, II, and III white (enameled). Ventral surfaces, flanks, upper arms, Fingers I and II, and Toes I and II not pigmented. Iris delimited by a black ring, background coloration o ff white to light grey with yellow shades and black dots and reticulation. Anterior third-to-half of parietal peritoneum white, posterior portion transparent. Visceral peritoneum white. Hepatic peritoneum transparent.

**Color in ethanol:** Obtained from Twomey et al. [19]. Dorsal and dorsolateral surfaces with relatively large cream spots bearing enameled warts and microspicules set in a lavender–greyish reticulum, which is formed by minute melanophores that are darker around the ocelli. Upper lip and tips of fingers and toes I, II, and III white (enameled). Ventral surfaces, flanks, upper arms, Fingers I and II, and Toes I and II not pigmented.

**Biology and ecology:** Very little is known about *Centrolene charapita*. Twomey et al. [19] report that, at the type locality, individuals were found perched on riverine vegetation during the night, and that sympatric amphibians included *Ameerega trivittata*, *Bolitoglossa altamazonica*, *Cochranella erminea*, *Hyloscirtus* sp., *Rulyrana mcdiarmidi*, *Pristimantis* <sup>a</sup>ff. *acuminatus*, *Pristimantis* sp., and *Rhaebo glaberrimus*. Parental care is unknown.

**Call:** Unknown.

**Tadpole:** Not described.

**Distribution** (Figure 31): *Centrolene charapita* is known from the type locality, a stream (5◦18-3.86" S, 78◦23-44.57" W, 682 m) near La Oliva, Peru [19], and Reserva Natural Maycu (4.2◦ S, 78.6◦ W, 940–1219 m) in southeast Ecuador.

**Figure 31.** Distribution of *Centrolene charapita* in Ecuador (yellow dots).

**Conservation status:** The conservation status of *Centrolene charapita* has not been evaluated by the IUCN. In Ecuador, populations are within a private reserve (Reserva Natural Maycu). The whole distribution range of the species is within a mining concession. Based on IUCN criteriaB2, Ba, Bb(iii), we sugges<sup>t</sup> that *C*. *charapita* should be considered as *Critically Endangered* in Ecuador.

**Evolutionary relationships** (Figure 24): Our phylogeny places *Centrolene charapita* as the sister species to a clade formed by several *Centrolene* species. A previous analysis had inferred *C*. *charapita* as sister to *C*. *geckoidea* [19].

**Specimens examined:** *Centrolene charapita:* Ecuador: *Provincia de Zamora Chinchipe:* Reserva Natural Maycu (4.207◦ S, 78.630◦ W, QCAZ 66783; 4.222◦ S, 78.645◦ W, QCAZ 66786–87; 4.229◦ S, 78.616◦ W, QCAZ 66785; 4.226◦ S, 78.620◦ W, QCAZ 66784).

*Centrolene condor* Cisneros-Heredia and Morales-Mite 2008 [107] (Figures 32 and 33).

*Centrolene condor* Cisneros-Heredia and Morales-Mite, 2008 [107]. Holotype: QCAZ 37279. Type locality: "Destacamento Militar Cóndor Mirador, western slope of the Cordillera del Cóndor (03◦18-25" S, 78◦23-36" W, between 1750–1850 m elevation), Provincia de Zamora Chinchipe, República del Ecuador".

**Common names:** English: Condor Glassfrog. Spanish: Rana de Cristal del Cóndor.

**Etymology:** The name of this species is in reference to its type locality, Cordillera del Cóndor, a mountain chain shared by Ecuador and Peru [107].

**Identification:** *Centrolene condor* can be distinguished from all other glassfrogs by having a green dorsum with many small yellowish–white flecks and dark bluish-black/brown flecks and punctuations (Figure 32), sloping snout in lateral view, light labial stripe, vomerine teeth, small humeral spine in males, enameled ulnar fold, and enameled metatarsal fold followed by a row of distinct enameled tubercles along the outer edge of the tarsus. Among Ecuadorian centrolenids, only *C*. *pipilata* shares a similar dorsal pattern, but *C*. *condor* has vomerine teeth (absent in *C*. *pipilata*) and a small, curved humeral spine (larger and straight in *C*. *pipilata*).

**Figure 32.** *Centrolene condor* in life. Ecuador, Zamora Chinchipe province, Paquisha, EPN 11343. Photo by Ana Almendáriz.

**Diagnosis:** *Centrolene condor* is diagnosed by the following traits (modified from Cisneros-Heredia and Morales-Mite [107]): (1) Vomerine teeth present; (2) snout subacuminate in dorsal view and sloping in profile; nostrils slightly elevated, producing depression in the internarial area; (3) tympanic annulus visible, vertical, with slight dorsolateral orientation; tympanic membrane not differentiated from surrounding skin; (4) dorsal skin shagreen, but with low warts and abundant spicules; (5) ventral skin granular; subcloacal area also granular with several enameled warts; (6) upper two-thirds of parietal peritoneum covered by iridophores (condition P3), pericardium white, all other peritonea not covered by iridophores (condition V1); (7) liver lobed, lacking iridophores (condition H0); (8) small humeral spines present in adult males; (9) webbing absent between Fingers I and II, basal between II and III, moderate between outer fingers: III 2—2− IV; (10) webbing between toes moderate: I 11/2—2<sup>+</sup> II 1—2<sup>+</sup> III 1—2 IV 2—1 V; (11) enameled ulnar fold; enameled fringe on edge of toe V that continues into thin enameled metatarsal fold and then into row of enameled tubercles along outer edge of tarsus; (12) nuptial excrescences present, Type I; concealed prepollex; (13) first finger shorter than second; (14) eye diameter larger than width of disc on Finger III; (15) in life, green dorsum with abundant yellowish–white flecks and abundant dark flecks; green bones; (16) in preservative, dorsal surfaces greyish with slight lavender hue and abundant light and dark flecks; (17) in life, iris cream–yellow with fine dark reticulation; in preservative, iris light grey with fine dark reticulation; (18) melanophores absent from fingers and toes, except for few on dorsal surfaces of outer fingers and outer toes; (19) males call from upper side of leaves; call composed by two pulsed notes, with dominant frequency at 2.62–2.97 KHz; (20, 21, 22) parental care, fighting behavior, egg clutches, and tadpoles unknown; and (23) medium body size, SVL in adult males 23.2–27.6 mm (X = 25.4 ± 1.826; *n* = 5); females unknown.

**Color in life** (Figure 32): Green dorsum with abundant yellowish–white flecks and dark punctuations. Enameled spots and yellowish–white flecks on arms and legs. Whitish–yellow labial line present. Enameled arm and leg folds. Green bones [107].

**Color in ethanol:** Dorsal surfaces greyish with slight lavender tint, with abundant light and dark flecks. Anterior two-thirds of ventral parietal peritoneum white, pericardium white, all other peritonea lack white lining (modified from Cisneros-Heredia and Morales-Mite [107]).

**Biology and ecology:** *Centrolene condor* is a recently described species and little information is available on its natural history. It is nocturnal and males call from amidst the leaves of riverine

vegetation a few centimeters over water in mature elfin forest. The species seems to be fairly common at Loma Tigres Bajo, where about 30 males were heard calling [108]. Tadpoles have a bright red coloration and are benthic [108].

**Call:** The advertisement call has a duration of 650–700 ms (*n* = 3); it is similar to a trill, composed of two pulsed notes; the first note has a duration of 435–510 ms and is conspicuously longer than the second (101–102 ms); the time between notes is 66–118 ms, and the dominant frequency is 2.62–2.97 KHz [108].

**Tadpole:** Not described.

**Distribution** (Figure 33): *Centrolene condor* is endemic to Ecuador, from localities in the Cordillera del Cóndor, Ecuador, at an elevation of 1737–2920 m [107,108]. The species is distributed within the Eastern Montane Forest ecoregion. Additional searches in the Cordillera del Cóndor have not yielded additional localities for the species [108].

**Conservation status:** *Centrolene condor* is currently listed as *Data Deficient* by the IUCN [109]. Given that the species is known from few localities in an isolated mountain range (Cordillera del Cóndor) with extensive mining activities and associated deforestation and contamination, we sugges<sup>t</sup> considering the species as *Endangered*—EN B1ab(iii), at the global and local levels, in agreemen<sup>t</sup> with Almendáriz and Batallas [108].

**Evolutionary relationships** (Figure 24): Terminals identified as *Centrolene condor* are placed in di fferent positions in the tree. Thus, it is likely that more than one species is found in what is currently recognized as *C*. *condor*.

**Specimens examined:** *Centrolene condor:* Ecuador: Provincia Zamora Chinchipe: Destacamento Militar Cóndor Mirador, western slope of the Cordillera del Cóndor (03◦18-25" S, 78◦23-36" W, 1750–1850 m), QCAZ 37279.

**Figure 33.** Distribution of *Centrolene condor* in Ecuador (yellow dots).

#### *Centrolene geckoidea* Jiménez de la Espada 1872 [83] (Figures 34–36).

*Centrolene geckoideum* Jiménez de la Espada, 1872 [83]. Holotype: MNCN 1596. Type locality: "las riberas del río Napo en el Ecuador". See comment in Distribution. *Centrolene geckoidea*—Barrio-Amorós, Rojas-Runjaic, and Señaris, 2019 [85].

## **Common names:** English: Gecko Glassfrog. Spanish: Rana de Cristal Geco.

**Etymology:** The specific epithet *geckoidea* refers to the enormous size of the discs on fingers and toes of this species, which resemble those of gecko lizards (Gekkonidae). For almost 150 years, this species was known as *C. geckoideum*, but its specific ephited was recently modified to *geckoidea* [85].

**Identification:** *Centrolene geckoidea* is unique among centrolenids in having a giant body size (adult males, SVL 70.2–80.7 mm; females, SVL 61.8–72.9 mm) and webbing between the two innermost fingers (Figure 35). Males also have a conspicuous humeral spine (Figure 34), which in some individuals, perforates the skin of the arm. Only *C*. *paezorum*, endemic of the high Andes of Colombia, could be confused with *C*. *geckoidea; C*. *paezorum* is known only from a single female and is reported to be smaller (SVL 44.5 mm; see Remarks) and with less hand webbing than *C*. *geckoidea* [110].

**Figure 34.** *Centrolene geckoidea* in life. Ecuador, Carchi province, Río La Plata (00◦48- N, 78◦02- W; 2525 m), on the Maldonado–Tulcán road, DHMECN 0900. Photo by Doug Wechsler (25 July 1988).

**Diagnosis:** (1) Each vomer with four or five teeth; (2) snout truncated in dorsal and lateral profiles (Figure 35); (3) tympanum visible and small, oriented almost vertically, its diameter 40.3%–50.0% of eye diameter; supratympanic fold moderate; tympanic membrane completely pigmented, differentiated from surrounding skin; (4) dorsal surfaces of males and females covered with warts, spicules evident only in males; (5) ventral surfaces of thighs below vent lacking pair of enlarged warts; (6) anterior two-thirds or the entire ventral parietal peritoneum white (conditions P3–P4); silvery white pericardium; no iridophores in peritonea covering intestines, stomach, testes, kidneys, gall bladder, and urinary bladder (condition V1); (7) liver tetralobed, lacking iridophores (condition H0); (8) in males, humeral spines present; (9) webbing present, but reduced between Fingers I, II, and III; extensive webbing between Fingers III and IV; hand webbing formula I 2—(2–2+) II (1–1+)—(2<sup>3</sup>/4–3+) III (1<sup>1</sup>/3–12/3)—1 IV (Figure 35); (10) webbing formula on foot I 0<sup>+</sup>—(0<sup>+</sup>–1) II 0<sup>+</sup>—(0<sup>+</sup>–1) III 0<sup>+</sup>—(1–1<sup>1</sup>/2) IV (1–1<sup>1</sup>/2)—0+ V; (11) ulnar fold with small, white tubercles; inner tarsal fold low, short; outer tarsal fold low, with small, white tubercles; (12) concealed prepollex; in males, nuptial pad Type I; (13) Finger I about same length as Finger II (Finger I 91.7%–100.0% of Finger II); (14) disc of Finger III wide, about 115%–130% of eye diameter; (15) in life, dorsum dull green to dark grey; upper lip yellow; bones green; (16) in preservative, dorsal surfaces grey to dark grey; (17) iris greenish gold with fine black reticulation; (18) melanophores covering dorsal surfaces of hands and feet; (19) males call from rocks behind waterfalls or within or near spray zones of fast-flowing streams; call loud, high-pitched, trilled whistle that lacks any consistent pattern of amplitude modulation; weakly to moderately pulsed, duration 155–373 ms; emitted infrequently at intervals of 1.48–5.05 min; dominant frequency modulated, 3468–4187 Hz; (20) fighting behavior unknown; (21) black eggs deposited on rocks in spray zones of streams; males provide prolonged parental care; (22) tadpoles dark, labial tooth row formula (LTRF) 2/3, but see below; (23) giant body size, males SVL 70.2–80.7 mm ( X = 75.2, *n* = 12); females, SVL 61.8–72.9 mm ( X = 68.1, *n* = 9).

**Figure 35.** *Centrolene geckoidea*. ( **A**) Head in lateral view, male, KU 116447. (**B**) Drawing of holotype, not to scale [83]. ( **C**) Hand in ventral view, male, KU 116447; drawing by Juan M. Guayasamin. (**D**) Humeral spine of adult female; modified from Rueda-Almonacid [111]. (**E**) Humeral spine of adult male; modified from Rueda-Almonacid [111].

**Color in life** (Figure 34): Dorsum dull green, with enameled greenish or bluish warts; throat greenish yellow; margin of upper lip yellow; venter cream or yellow cream; ulnar, tarsal, and cloacal tubercles creamy white; white flecks on flanks; iris pale greenish gold with fine black reticulation; palpebrum clear (W. E. Duellman field notes, 9 April 1975; this work); bones green [111]. Males and females are dark grey to brownish green during the night [112].

**Color in ethanol:** Dorsal surfaces of head, body, and limbs cream grey to dark grey with tips of spicules being white; cloacal, ulnar, and tarsal tubercles white; ventral surfaces cream. Anterior two-thirds of the ventral parietal peritoneum white, posterior third transparent; pericardium white; no iridophores in peritonea covering liver, kidneys, and digestive tract.

**Biology and ecology:** Males and females of *Centrolene geckoidea* have been found clinging to vertical or overhanging rock surfaces in the spray zone behind waterfalls [112–114]. Males have remarkable call-site fidelity. Egg clutches are deposited on rocks within the spray zone and contain 89–112 black eggs, which are glued to the rocks by a brittle jelly unknown in other centrolenids [112,113]; an "empty space" is evident in the center of the attached clutch [113]. Although oviposition has not been observed, Grant et al. [112] suggested that the ova may be deposited as the female rotates through a circle with the head at the center, a scenario that would explain the origin of the "empty space" near the center of the egg mass. During the night, males have been observed sitting on or near up to four clutches of eggs while calling. During the day, males also have been observed sitting near or on clutches on the rockface behind a waterfall or hidden in spaces between rocks [112]. Thus, all observations by Grant et al. [112] sugges<sup>t</sup> that males provide prolonged parental care to clutches.

**Call:** Grant et al. [112] described the call of *Centrolene geckoidea* from El Queremal (3.483 N, 76.7 W), Valle del Cauca, Colombia. The information shown below is based on their study. Males call from behind waterfalls or within or near spray zones of fast-flowing streams. Males have call-site fidelity and have been observed vocalizing at the same site for up to a month. The call is a loud, high-pitched, trilled whistle that lacks any consistent pattern of amplitude modulation. The call is weakly to moderately pulsed and has a duration of 155–373 ms. Calls were emitted infrequently at intervals or 1.48–5.05 min; however, males typically call less frequently (i.e., as little as less than once per hour). The dominant frequency is at 3468–4187 Hz, and it is modulated, beginning at low frequencies (3593–3781 Hz) and rising to a maximum of 3718–4187 Hz, after which it falls, ending at 3468–3718 Hz.

**Tadpole:** Lynch et al. [113] and Rueda-Almonacid [111] provide descriptions and illustrations of the tadpole of *Centrolene geckoidea*. Lynch et al. [113] briefly described a tadpole (total length of 22.3 mm) as having a typical centrolenid body form; mouth lacking upper tooth rows, but with two evident lower rows (P1 with a wide medial gap); upper jaw sheath thick with minute serrations; lower jaw sheath thin and poorly keratinized; one row of large subconical marginal papillae borders the oral disc ventrolaterally and posteriorly. Rueda-Almonacid [111] mentioned that tadpoles in Gosner stage 22, one month after hatching, had two incomplete tooth rows on the anterior labium and three tooth rows on the posterior labium. However, three months after hatching, all the tooth rows were lost, and only dermal ridges were evident [111]. The dorsal surfaces of the body and the tail musculature were black, and the venter lacked pigmentation [111].

**Distribution** (Figure 36): *Centrolene geckoidea* occurs across the three Andean Cordilleras of Colombia (Cordillera Occidental, Central, and Oriental; in the departments of Antioquia, Valle del Cauca, Caldas, Quindio, Risaralda, Tolima, Boyacá, and Caquetá), south to the Pacific Andean slope of Ecuador (Carchi and Pichincha provinces) at elevations of 1750–2525 m [111–116] (Figure 35). In Ecuador, the potential distribution of the species covers an area of 10,579 km<sup>2</sup> within the Western Montane Forest region.

Jiménez de la Espada [83] mentioned that the species was found at *"las riberas del Río Napo en el Ecuador"*. During his trip in South America, Jiménez de la Espada visited several eastern Andean localities (e.g., Basin of Río Quijos, San José de Moti, Cordillera de Guacamayos, Cosanga) before reaching the lowlands near the Río Napo. It has been suggested that the type locality is in error [110], but the holotype of *C*. *geckoidea* could have been collected in the headwaters of the Napo river, or at one of the eastern Andean localities [17].

**Figure 36.** Distribution of *Centrolene geckoidea* in Ecuador (yellow dots).

**Conservation status:** Globally, *Centrolene geckoidea* is listed by the IUCN as a *Critically Endangered* species [117]. In Ecuador, the species has a severely fragmented distribution, and evidence of population declines. Intensive fieldwork in historical localities such as Quebrada Zapadores has failed in finding the species [91] (JMG, pers. obs.; DFCH, pers. obs.). The last reports of *C*. *geckoidea* in Ecuador are from Río La Plata (00◦48- N, 78◦02- W; 2525 m), on the Maldonado–Tulcán road, on 25 July 1988, and from Bosque Protector Río Guajalito in January to May between 1998 and 1999 [17]. A similar situation exists for populations of *C*. *geckoidea* found at Valle del Cauca in the Cordillera Occidental (Colombia), as they have not been seen for more than 10 years (W. Bolivar and J.J Sarria-Ospina, pers. com.).

**Evolutionary relationships** (Figure 24): The molecular tree reported by Twomey et al. [19] places *Centrolene geckoidea* as the sister species of *C*. *charapita*. However, our inferred tree recovers *C*. *geckoidea* as sister to all other *Centrolene* species. Since *C*. *geckoidea* is the type species for the genus *Centrolene*, its phylogenetic placement has fundamental taxonomic implications.

**Remarks:** The external morphology, osteology, and myology of *Centrolene geckoidea* was studied in detail by Rueda-Almonacid [111]. Given the remarkable morphological similarly between *C*. *geckoidea* and *C*. *paezorum*, we consider the possibility that *C*. *paezorum* represents a junior synonym of *C*. *geckoidea*. Differences between these species include the absence of vomerine teeth in *C*. *paezorum*, smaller size, and reduced webbing [110]. Also, the two species occupy different elevations; *C*. *geckoidea* is found at elevations between 1750–2525 m, whereas *C*. *paezorum* occurs at 3030 m. Additional specimens from the type locality of *C*. *paezorum* (Colombia: Departamento del Cauca: km 55–56 on the Popayán–Inza road, 3030 m) are necessary to clarify its status. Until recently, the holotype of *Centrolene geckoidea* was thought to be lost [118], but in a recent publication, González-Fernández [119] provided dorsal and ventral photographs of the holotype (MNCN 1596).

**Specimens examined:** *Centrolene geckoidea:* Ecuador: *Provincia de Pichincha:* 1 km SW of San Ignacio (0.4486 S, 78.7478 W, 1920 m), KU 178015–17; Quebrada Zapadores, 5 km ESE of Chiriboga on Chiriboga–Quito road (0.245278 S, 78.7261 W; 2010 m), KU 164492; 9 km SE of Tandayapa (0.0167 S, 78.683 W; 2150 m), KU 164490–91. *Provincia del Carchi:* Río La Plata, on the Maldonado-Tulcán road (0.8 N, 78.033 W; 2525 m), DHMECN 0900.

*Centrolene heloderma* (Duellman, 1981 [120]; Figures 37–40).

*Centrolenella heloderma* Duellman, 1981 [120]. Holotype: KU 164715.

Type locality: "Quebrada Zapadores, 5 km east-southeast of Chiriboga, 2010 m, Provincia de Pichincha, Ecuador (00◦17- S, 78◦47- W)".

*Centrolene helodermum*—Ruiz-Carranza and Lynch, 1991 [6].

*Centrolene heloderma*—Guayasamin, Castroviejo-Fisher, Trueb, Ayarzagüena, Rada, and Vilà, 2009 [1].

**Common names:** English: Warty Glassfrog. Spanish: Rana de Cristal Verrugosa.

**Etymology:** The specific epithet *heloderma* combines the Greek words "helos" (wart) and "derma" (skin) and is used in allusion to the dorsal texture of the species.

**Identification:** *Centrolene heloderma* differs from all glassfrogs by having a green pustular dorsum and males with humeral spines (Figure 34). *Centrolene heloderma* mostly resembles *Centrolene buckleyi*; both species have humeral spines in males, snout inclined in lateral profile, and a narrow white labial stripe. The most conspicuous difference between these species is that *Centrolene buckleyi* lacks a pustular dorsal skin. Further, *C*. *buckleyi* differs by having a concealed tympanum (completely visible in *C*. *heloderma*; Figure 37).

**Figure 37.** *Centrolene heloderma* from Reserva Las Gralarias, Ecuador. (**A**,**B**) Adult male. (**C**) Egg clutch. (**D**) Egg clutch parasitized by larvae of Drosophilidae fly. Photos by Jaime Culebras.

**Diagnosis:** (1) Vomers lacking teeth; (2) snout subacuminate in dorsal profile, inclined anteriorly from nostrils to margin of lip in lateral profile (Figures 37 and 38); (3) tympanum completely visible, oriented almost vertically, relatively large, its diameter 38.5%–44.5% of eye diameter; supratympanic fold moderate; tympanic membrane pigmented, clearly differentiated from surrounding skin; (4) dorsal surfaces of males and females pustular; in males, minute spicules evident only on flanks and tympanic region; (5) pair of enlarged subclocacal warts; (6) anterior three-fourths of ventral parietal peritoneum

with white iridophores (condition P3); white pericardium; no iridophores in peritonea covering intestines, stomach, kidneys, testes, gall bladder, and urinary bladder (condition V1); (7) liver tetralobed, lacking iridophores (condition H0); (8) in males, humeral spines present; (9) webbing absent between Fingers I, II, and III; moderate webbing between Fingers III and IV; webbing formula III (2–2<sup>1</sup>/2)—(12/3–2+) IV (Figure 37); (10) webbing formula on foot: I (1<sup>1</sup>/4–11/2)—2 II (1–1<sup>+</sup>)—(2<sup>+</sup>–21/4) III (1–1+)—(2–2+) IV (2<sup>+</sup>–21/2)—(1–11/4) V; (11) external ulnar fold evident, white; inner tarsal fold low, short; outer tarsal fold long, with low white tubercles; (12) concealed prepollex; in males, nuptial pad Type I; (13) Finger II slightly longer than Finger I (Finger I 91.0%–95.5% of Finger II); (14) disc of Finger III of moderate width, about 59.3%–74.2% of eye diameter; (15) in life, dorsum green with green to bluish white warts; upper lip white; bones green; (16) in preservative, dorsal surfaces dull lavender, sometimes with minute white or cream spots; (17) in life, iris yellow to pale golden yellow with fine black reticulations; (18) melanophores mostly absent from fingers and toes, except for some on Finger IV, and Toes IV and V; (19) males call from upper sides of leaves near streams; call short (133–188 ms, mean = 161 ms, SD = 15.4 ms), with two notes per call; notes strongly pulsed; dominant frequency at 4393–4823 (mean = 4682, SD = 104) Hz; (20) fighting behavior unknown; (21) egg placed on the upper surfaces of leaves; parental care unknown; (22) tadpoles unknown; (23) medium body size, male SVL 26.8–31.5 mm ( X = 29.0, *n* = 17); in one female, SVL 32.3 mm.

**Figure 38.** *Centrolene heloderma*, male, KU 164718. ( **A**) Head in ventral view. (**B**) Hand in ventral view. Illustrations by Juan M. Guayasamin.

**Color in life** (Figure 37): Dorsum yellow green to dark green with green to bluish white pustules; margin of lip whitish yellow; ventral parietal peritoneum whitish yellow; throat pale greenish yellow; cloacal, heel, and ulnar tubercles white; heart not visible; bones green; iris yellow to pale golden yellow with fine black reticulations [120].

**Color in ethanol:** Dorsal surfaces of head, body, forearms, thighs, and shanks dull lavender; other surfaces dull cream; flanks white; margin of upper lip and cloacal tubercles white (Duellman, 1981). White parietal peritoneum covering the anterior three-fourths of the venter; pericardium white; no iridophores in peritonea covering liver, intestines, stomach, kidneys, and urinary bladder.

**Biology and ecology:** During the rainy season (December–April), at night, *Centrolene heloderma* has been found active on vegetation near streams in primary and disturbed forest. Occasionally, males have been observed away from streams, probably looking for new territories [87]. Males call from the upper surfaces of leaves near streams. Egg clutches, with 25–29 brownish eggs, are placed on the upper side of leaves near streams [87]. At Reserva Las Gralarias, *C*. *heloderma* is abundant at Five-frog Creek, but has also been observed at Ballux Creek, Heloderma Creek, and Hercules Creek [88,92]. Parental care is unknown.

**Call** (Figure 39): The following description is based on the analysis of 58 notes contained within 29 calls from 3 individuals (LBE-C-001, 012, 015); individuals are from Río Alambí (2390 m), and Reserva Las Gralarias (1822–1864 m), in Pichincha province, Ecuador. The typical advertisement call is relatively short (range = 133–188 ms, mean = 161 ms, SD = 15.4 ms), and has two notes per call. Notes are strongly pulsed. The first note is longer than the second note (first note duration: Range = 38–76 ms, mean = 60.2 ms, SD = 9.89 ms; second note duration: Range = 17–44 ms, mean = 27.8 ms, SD = 6.283 ms). The two notes are also separated by an internote duration of 50–99 (mean = 72.9, SD = 9.5) ms. Notes are pulsed and similarly variable in number, with 2–7 (mean = 3.741, SD = 1.906) amplitude peaks throughout the note. The first note tends to have more pulses than the second note. Pulses within a note have a rate of 45.5–117.6 (mean = 83, SD = 15) pulses per second. Notes generally have their peak amplitude in the first 50% of the note (relative peak time: Range = 0.032–0.8697, mean = 0.273, SD = 0.242), but infrequently the first note can have its peak amplitude in the last 50% of the note. Frequencies between both notes are also highly similar. The dominant frequency of a note measured at peak amplitude is 4393–4823 (mean = 4682, SD = 104) Hz and is contained within the fundamental frequency. The fundamental frequency has a lower limit of 4221–4651 (mean = 4513, SD = 138) Hz and a higher limit of 4651–5082 (mean = 4875, SD = 104) Hz.

**Figure 39.** Call of *Centrolene heloderma* (LBE-C-012) recorded from Reserva Las Gralarias, Pichincha province, Ecuador. Note that each call has two distinctive pulsed notes.
