**4. Discussion**

Our study integrating molecular, acoustic and morphological information justifies the erection of the new genus of strabomantid frog *Qosqophryne*. The molecular phylogeny we inferred, the most complete phylogeny to date in terms of terminal sampling for genera of Holoadeninae [2,24], provides strong support for this new genus forming a sister clade to *Microkayla*. Furthermore, our phylogeny confirms taxonomic uncertainty regarding the genera *Noblella* and *Psychrophrynella* [2,19,20], suggests the presence of several undescribed species of *Noblella* and *Psychrophrynella*, and generalizes the idea of high species endemism in high elevation Andean strabomantids [2,4,19–22,49].

Morphological synapomorphies for the new genus *Qosqophryne* have not been recognized, and there does not appear to be a unique combination of meristic traits to distinguish all species of *Microkayla* from species of *Qosqophryne*. However, there are some characteristics that help distinguish the two genera. Some of the traits present in *Qosqophryne* but absent in *Microkayla* are fingers and toes with lateral fringes, venter smooth (areolate in *Microkayla*), and presence of dentigerous processes of vomers (but absent in *Q. flammiventris*). The structure of the advertisement call, when known, appears to be similar in both genera, i.e., a whistle-like call, but composed of a single note in *Microkayla* vs. 2–4 notes in *Qosqophryne* (except for *Q. gymnotis*). There is limited information on parental care, but it appears that females attend clutches in *Q. gymnotis* [39], whereas males attend clutches in *M. illimani* and *M. teqta* [50,51]. Similarly to *Qosqophryne*, females attend clutches in *B. cophites* [52], *B. hanssaueri* and *B. nubilosus* (Catenazzi, pers. obs.). However, we lack natural history information from most species of strabomantid frogs, and thus any generalization on parental care is premature.

In support of our proposed new genus, there is a wide gap, both in terms of airline distance and the highly dissected topography, in the distribution range of species of *Microkayla* and *Qosqophryne.* These are all highly endemic, terrestrial-breeding frogs most likely characterized by extreme low vagility, as suggested by their patchy distribution in cloud forests and grasslands. All species of *Microkayla* occur from extreme southern Peru (Department Puno) to the western limits of department Santa Cruz in central Bolivia (Serranía Siberia), whereas the three species of *Qosqophryne* occur in the Vilcabamba mountain range in the Peruvian Department of Cusco. The gap of 320 km by airline between the southernmost locality of *Qosqophryne* (*Q. gymnotis*; −13.07558, −72.38201) and the northernmost locality of *Microkayla* (*M. boettgeri*) overlaps with the distribution range of *Bryophryne*. At the northern limit, *B. abramalagae* and *B. bustamantei* are marginally sympatric with *Q. gymnotis*, whereas at the southern limit, *B. wilakunka* (Ayapata, Puno, −13.85294, −70.31450) occurs ~80 km NW of the type locality of *M. boettgeri* (Phara, Puno, −14.16247, −69.66250). Although many species in these genera of Holoadeninae are likely "micro-endemic", researchers have seldom invested much effort in documenting the distribution ranges of most species, and it is possible that some of these species occur more widely than presently known. Therefore, currently five genera of Holoadeninae occur in the tropical Andes south of the Apurimac canyon in Cusco, Puno and northern Bolivia: *Bryophryne*, *Psychrophrynella* and *Qosqophryne* in the Vilcabamba mountain range; *Bryophryne*, *Noblella* and *Psychrophrynella* in the Vilcanota range; *Bryophryne*, *Microkayala*, *Noblella* and *Psychrophrynella* in the Carabaya range, and *Microkayala* south of the Apolobamba range.

**Author Contributions:** Conceptualization, A.C., L.M., E.L. and R.v.M.; methodology, A.C., L.M., E.L. and R.v.M.; software, A.C. and R.v.M.; validation, A.C., L.M., E.L. and R.v.M.; formal analysis, A.C. and R.v.M.; investigation, A.C., L.M., E.L. and R.v.M.; resources, A.C. and R.v.M.; data curation, A.C., R.v.M.; writing—original draft preparation, A.C.; writing—review and editing, A.C., L.M., E.L. and R.v.M.; visualization, A.C., L.M., E.L. and R.v.M.; supervision, A.C.; project administration, A.C.; funding acquisition, A.C. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the Amazon Conservation Association, the Rufford Foundation, the Chicago Board of Trade Endangered Species Fund, and the Amphibian Specialist Group.

**Acknowledgments:** We thank the staff of the Museo de Biodiversidad del Perú (MUBI) for access to the herpetological collection.

**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

## **Appendix A. Specimens Examined**

*Bryophryne abramalagae*: PERU: CUSCO: Provincia La Convención: Distrito de Huayopata, Abra de Málaga (13◦07-23.8-- S, 72◦20-51.2-- W), 4000 m a.s.l., MUSM 27630–32, MTD 47489–91.

*Bryophryne bakersfield*: PERU: CUSCO: Provincia La Convención: Distrito de Echarate, Roquerío de Lorohuachana, 3620 m a.s.l. (12◦29-43.8-- S, 72◦04-35.9-- W), MHNC 7972.

*Bryophryne bustamantei*: PERU: CUSCO: Provincia La Convención: Abra de Málaga: MUSM 24537–38.

*Bryophryne cophites*: PERU: CUSCO: Provincia de Paucartambo: Distrito Kosñipata: S slope Abra Ac[j]anaco, 14 km NNE Paucartambo, 3400 m a.s.l.: KU 138884 (holotype); N slope Abra Ac[j]anaco, 27 km NNE Paucartambo, 3450 m a.s.l.: KU 138885–908, 138911–5 (all paratypes); 2 km NE of Abra Ac[j]anaco, 3280 m a.s.l.: MHNG 2698.24, 5.5 km N of Abra Acanacu [Acjanaco], 3523 m: MUSM 27895, Tres Cruces, 8.5 km N of Abra Ac[j]anaco, 3590 m a.s.l.: MUSM 20855–56, 26283–84, 26264, 26266–67, 26313,26315,27896,30414–17,PillcoGrande,3865ma.s.l.,borderofManuNP:CORBIDI11919.

 near *Bryophryne flammiventris*: PERU: CUSCO: Provincia de La Convención, Distrito de Vilcabamba, road between Vilcabamba and Pampaconas, 3800 m a.s.l.: MUSM 27613 (holotype), MUSM 27612, 27614–15, MTD 46890–92 (paratypes).

*Bryophryne gymnotis*: PERU: CUSCO: Provincia de La Convención, Distrito de Huayopata: 1 km east of San Luis, 3272–3354 m a.s.l.: MUSM 24543 (holotype), MHNG 2710.28, 2710.29, MTD 46860–64, 47288, 47291–92, 47297, MUSM 24541–42, 24544–45, 24546–56, MVZ 258407–10 (paratypes).

*Bryophryne hanssaueri*: PERU: CUSCO: Provincia de Paucartambo, Distrito de Kosñipata: Acjanaco, Manu National Park, 3266 m a.s.l.: MUSM 27567 (holotype); from near Acjanaco, Manu National Park, 3280–3430 m a.s.l.: MHNG 2698.25, MTD 46865–66, 46887–89, MUSM 24557, 27568–69, 27607–11, MVZ 258411–13 (all paratypes).

*Bryophryne mancoinca*: PERU: CUSCO: Provincia de La Convención, Hornopampa sector, near Salkantay Mountain, along the road to the Archeological Complex of Choquequirao, 3707 m a.s.l.: MUBI 11152 (holotype), MUBI 11147–11151, 11153, 11154, 11159, 16068, 16069, 16074, 16083 (paratypes).

*Bryophryne nubilosus*: PERU: CUSCO: Provincia de Paucartambo: Distrito de Kosñipata, 500 m NE of Esperanza, 2712 m a.s.l.: MUSM 26310 (holotype), MUSM 26311; near the type locality, 13◦11-33.21-- S, 71◦35-25.17-- W, 3065 m: MTD 47294; near Hito Pillahuata, 2600 m: MUSM 20970; Quebrada Toqoruyoc, 3097 m a.s.l.: MUSM 26312, MTD 47293; Esperanza, 2800 m: MHNSM 26316–17; 13◦11-20.2-- S, 71◦35-07.3-- W, 2900 m a.s.l.: MUSM 24539–40.

*Bryophryne phuyuhampatu*: PERU: CUSCO: Provincia de Paucartambo: Distrito de Paucartambo, Quispillomayo valley, Área de Conservación Privada (ACP) Ukumari Llaqta, 2795–2850 m a.s.l., 13◦22-12.14-- S; 71◦6-49.82-- W (WGS84; type locality), CORBIDI 18224–18226, MUBI 14654 and 14655.

*Bryophryne quellokunka*: PERU: CUSCO: Provincia de Quispicanchis: Distrito de Marcapata: Coline, 3672 m a.s.l.: MUSM 27571, 27573.

*Bryophryne zonalis*: PERU: CUSCO: Provincia de Quispicanchis, Distrito de Marcapata, Kusillochayoc at 3129 m a.s.l.: MUSM 27570 (holotype), MTD 46867, 46869–70, MUSM 27572, 27574–75, 27861, MVZ 258414 (paratypes); at Puente Coline, 3285 m a.s.l.: MVZ 258415 (paratype).

*Microkayla boettgeri*: PERU: PUNO: Provincia de Sandia, Distrito de Limbani, Phara, 3466 m a.s.l.: MHNSM 19966 (holotype), MHNSM 19967–76, MTD 46508–9, 46512–19 (paratypes).

*Microkayla chapi*: PERU: PUNO: Provincia de Sandia, Distrito de Limbani, 3.7 km from Sina, Hirigache River valley, 3466 m a.s.l.: MUBI 5326 (holotype), MUBI 5325, 5327, 5330, 5331, 5328, 5329 (paratypes).

*Microkayla chilina*: PERU: PUNO: Provincia de Sandia, Distrito de Limbani, 3.7 km from Sina, Hirigache River valley, 3466 m a.s.l.: MUBI 5355 (holotype), MUBI 5350, 5351, 5353, 5354 (paratypes).

*Qosqophryne flammiventris*: PERU: CUSCO: Provincia de La Convención, Distrito de Vilcabamba, road between Vilcabamba and Pampaconas, 3800 m a.s.l., MUBI 13365.

*Qosqophryne gymnotis*: PERU: CUSCO: Provincia de La Convención, Distrito de Huayopata: San Luis, MUBI 14315–14319.
