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Article

A Small Piece of a Complicated Puzzle: The Resurrection of Randia tomatillo Loes. from the Randia aculeata L. Complex (Rubiaceae)

by
Alejandro Torres-Montúfar
1,* and
Mayte Stefany Jiménez Noriega
2
1
Herbario FES-Cuautitlán, Departamento de Ciencias Biológicas, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México (FESC-UNAM), Carretera Cuautitlán Teoloyucan km 2.5, San Sebastián Xhala, Cuautitlán Izcalli C.P. 54714, Mexico
2
Jardín Botánico FES-Cuautitlán, Departamento de Ciencias Biológicas, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México (FESC-UNAM), Carretera Cuautitlán Teoloyucan km 2.5, San Sebastián Xhala, Cuautitlán Izcalli C.P. 54714, Mexico
*
Author to whom correspondence should be addressed.
Taxonomy 2025, 5(1), 10; https://doi.org/10.3390/taxonomy5010010
Submission received: 16 January 2025 / Revised: 13 February 2025 / Accepted: 14 February 2025 / Published: 18 February 2025
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Abstract

:
Within the Rubiaceae family, the genus Randia comprises approximately 90 species, with significant morphological diversity in growth forms, leaf shapes, and floral sexuality. In particular, Randia aculeata is a taxonomically challenging species distributed from the southern United States to South America and the Antilles that exhibits high morphological variability and ecological adaptability. One of its synonyms is Randia tomatillo, originally described from coastal dunes in Veracruz, Mexico, and it has been inconsistently described in the taxonomic literature either as a distinct species or as a synonym for R. aculeata. This study aimed to resolve the taxonomic identity of R. tomatillo through morphological observations from herbarium specimens, and transverse sections from mature leaves were observed using SEM microscopy to explore crystal types. Morphological traits, such as lifeform, twig pubescence, stipule persistence, fruit size, and pericarp texture, are critical in distinguishing R. tomatillo from morphologically related species, such as R. aculeata and Randia thurberi. Anatomical features, particularly the presence of prisms in the leaf mesophyll and epidermis, are unique to R. tomatillo, suggesting their diagnostic value. Ecological adaptations, such as scandent growth and spongy pericarps for hydrochorous fruit dispersal, further support its distinction as a species adapted to coastal environments. These findings highlight the need for a comprehensive taxonomic reassessment of Randia, integrating morphological, anatomical, and ecological evidence.

1. Introduction

The neotropical genus Randia L. belongs to the Rubiaceae family and is a member of the tribe Gardenieae, which comprises approximately 90 species [1,2,3,4]. The morphology of the genus is diverse with regards to habitat (trees, shrubs, and lianas), leaf shape, and floral sexuality (mainly dioecious, but with some bisexual species). Randia is characterized by the presence of brachyblasts bearing clustered stipules and leaves, pollen grains released in tetrads, and fleshy fruits containing numerous discoidal seeds embedded in a dark pulp [2,4,5,6,7,8].
In Mexico, the genus Randia is particularly diverse, standing out as the second most diverse genus, with 64 species after Arachnothryx Planch. (65 spp.) [9]. Species identification within Randia is notably challenging due to morphological diversity and the absence of a comprehensive revision of the genus. Additionally, molecular studies have shown that Randia is polyphyletic, with its species scattered across different clades within Gardenieae. This has led to some taxa being transferred to other genera, new genera being described, or others being synonymized as Casasia A. Rich., Rosenbergiodendron Fagerl., or Tocoyena Aubl. [1,3]. At the species level, an example of the taxonomic problem is Randia aculeata L., a name widely used for specimens collected in several regions in Mexico, e.g., dry forests, coastal dunes, tropical rain forests, and cloud forests, so it is considered morphologically variable. Therefore, the species has become a complex species, and its circumscription needs a comprehensive and exhaustive evaluation of its whole distribution area, from southern USA to South America and the Antilles [5].
By far, the most recent and comprehensive taxonomic treatment for Mexican Rubiaceae includes 55 species of Randia for the country [6], in which seven names are treated under the synonymy of Randia aculeata. One of these synonyms is Randia tomatillo Loes., a species described in 1922 for plants growing in coastal dunes in Veracruz [10], in the eastern region of Mexico. In fact, apparently, it is adapted to hydrochory due to its fruits with spongy pericarps [5]. The taxonomic conflict of R. tomatillo arises because Borhidi [6,11] considers it a synonym of Randia aculeata var. dasyclada Steyerm. However, in the taxonomic treatment of Flora Mesoamericana, R. tomatillo is treated as a separate entity from R. aculeata [5], as well as in the Mexican Rubiaceae list [9] and the checklist of the vascular plants of Mexico [12].
For Rubiaceae, the systematic value of the crystals has been evaluated at different taxonomic levels; for example, the presence of raphides is diagnostic for the Rubioideae subfamily in some classification schemes [13,14] and at the generic and species levels [15,16,17]. Since some authors suggest that soil influences the type of crystals [18], one of the objectives is to explore the type of crystals in R. tomatillo to assess their taxonomic value and evaluate the taxonomic identity of Randia tomatillo, considering morphological and ecological observations to distinguish it from Randia aculeata.

2. Materials and Methods

2.1. Morphological and Taxonomic Study

Extensive examinations were carried out on herbarium collections from ENCB, FESC, MEXU, and XAL (acronyms according to [19]). The selected species were the specimens that fit into the circumscription of R. tomatillo, plus the morphologically closely related species identified as R. aculeata and R. thurberi. These collections, as well as images of material type and specimens from MO, NY, TEX, and the US, were studied. Descriptions of the species were based on characters observed on herbarium specimens and complemented with descriptions from the specialized literature [5,6,7,11]. The specimens were observed under the stereomicroscope American Optical Mod. 570 (Buffalo, NY, USA), and the measurements were taken using a ruler on the rehydrated materials of the leaves, florets, and fruits. Distribution and ecological data were directly obtained from herbarium labels. The distribution maps were drawn using locality data from all consulted herbarium specimens using QGIS Desktop v.3.4.11 [20].

2.2. Calcium Oxalate Crystals

Three individuals per species were selected from specimens deposited at FESC and MEXU herbaria. From each individual, three mature leaves were selected, from which a 1 × 1 cm part was sectioned, and hand-made transverse sections were performed. The specimens were dehydrated in a graded ethyl alcohol series (50–100%), remaining for 24 h in each concentration, and dried at the critical point with carbon dioxide. The specimens were mounted on a metal stub with carbon adhesive tabs, then gold coated and examined at 15 kV in a Hitachi Stereoscan Model SU1510 SEM (Hitachi Ltd., Tokyo, Japan) at the Laboratorio de Microscopia y Fotografia de la Biodiversidad, Instituto de Biologia, Universidad Nacional Autonoma de Mexico.

3. Results

The lifeform, twig pubescence, stipule persistence, fruit size, and its pericarp texture were the most useful characteristics in distinguishing among the taxa (Table 1). The only constant characters among the three species evaluated are the paired spines of similar size (range of 4 to 26 mm long) and the spheroidal to ellipsoid fruits. The leaf characters, such as size, the form of the lamina, apex, and base, are quite similar among the species and very variable even in the same specimen, so they have a high overlap (Table 1; Figure 1).
For R. thurberi, the corolla tube length (12 to 16 mm vs. 2 to 10 mm in R. aculeata and R. tomatillo) and the fruit size (>30 mm vs. <25 mm in R. aculeata and R. tomatillo) are useful characters to distinguish R. thurberi from the other morphologically related species (Table 1).
Randia tomatillo can be diagnosed by a combination of several characters: the scandent shrub lifeform (vs. treelets or shrubs in R. aculeata and R. thurberi), the hirtulose twig pubescence (vs. glabrate or puberulent in R. aculeata and R. thurberi), the coriaceous leaf texture (vs. papyraceous to subcoriaceous in R. aculeata and only papyraceous in R. thurberi), the deciduous stipules (vs. persistent in R. aculeata and R. thurberi), and the spongy fruit pericarp (vs. sclerified pericarp in R. aculeata and R. thurberi) (Figure 1 and Figure 2). In addition, the three species have druses in the leaf mesophyll, and only R. tomatillo has prisms (Figure 3). Also, R. tomatillo grows in coastal dunes, while R. thurberi grows in dry forests, and R. aculeata is widespread on different vegetation types (Table 1). The geographical distribution is similar in the three species studied in Mexico and Central America, and only R. aculeata is distributed from North America (Florida) to northern South America and the Antilles. R. tomatillo is also found in the coastal region of northern South America (Colombia) (Table 1, Figure 4).
Taxonomic description
Randia tomatillo Loes., Repert. Spec. Nov. Regni Veg. 18: 360 (1922). LECTOTYPE: México, Veracruz, Seler y Seler 4498 (US!) (designated by Lorence in 1999 [21]).
Scandent shrubs are up to 4 m tall, armed with paired spines with a length of 5–16 mm and hirtellous twigs. Leaves are 0.9–9.3 × 0.4–4.5 cm, narrowly to broadly obovate or obovate-elliptic or rarely ovate or ovate-elliptic in shape, generally isophyllous, clustered at the apex of long shoots and on spur branches, coriaceous and glabrous on both surfaces; their base is rounded, obtuse, or acute and attenuate; the apex is obtuse to rounded; the secondary veins are in 5–7 pairs; the petioles are 0–15 mm. Stipules are 1.5–3 mm, broadly triangular to ovate-triangular in shape, acuminate to cuspidate, hirtellous externally, sparsely sericeous internally, and deciduous. Flowers are unisexual, with a corolla hypocrateriform, glabrous externally, glabrous internally, except for a scattered to densely villous indumentum in the throat and at the base of the lobes; tubes are 4–8 mm; the lobes are five, 5–8 mm in size, ovate, and acuminate; the calyx limb is 1.5–2.5 mm, with five lobes, 0.2–1 mm in size, and subulate. Staminate flowers are one or two, terminal on spur branches, subsessile, or with pedicels of up to 1 mm; the hypanthium is 1–1.5 mm, glabrous, smooth, or slightly ribbed; the anthers are 2.5–3 mm; the pistillode is c. 5 mm. Pistillate flowers are solitary, terminal, and subsessile; the hypanthium is 5–6 mm, cylindrical-ovoid, glabrous, smooth, or slightly ribbed; the staminodes are c. 2 mm; the stigmas are c. 3 mm. Fleshy fruits, berries, are 18–25 × 10–20 mm, ellipsoidal, glabrous, whitish-colored, and smooth with a spongy pericarp. Seeds are flattened and 6–7 mm in diameter.
Distribution and habitat—Rogiera amoena is distributed in coastal dunes from the Gulf of Mexico, from Mexico, Panama, and Colombia, occurring from 0 to 25 m.
Phenology—Collected with flowers in May and June and with fruits all along the year.
Additional specimens examined—MEXICO. Campeche, 20 km al SE de Champooton, camino Champoton Cd. del Carmen, 9 February 1983, E. Martínez 3090 (MEXU). Tabasco, Tacotalpa, 2 km abajo (NW) de Tapijulapa, 30 May 1982, C. P. Cowan 3510 (MEXU). Tamaulipas, Aldama, Barra del Tordo, 11 May 1982, P. Moreno 755 (MEXU), Costa a 5 km. al E de El Pozo de Petroleos, al S de Barra de Ostiones, 7 January 1971, E. Martínez Ojeda 117 (MEXU); Altamira, Bocatoma Sur, donde inicia el camino a Punta Jerez, P. Moreno 675, 5 May 1982 (MEXU); Soto La Marina, 1 km al E del Tepehuaje, 4 January 1971, E. Martínez Ojeda 20 (MEXU). Quintana Roo, Islote en el balneario Xel-ha a 122 km de Carrillo Puerto, 21 November 1981, A. Magaña 2116 (MEXU). Veracruz, Actopan, 3.5 km al N de La Mancha, 5 August 1992, S. Sinaca 1833 (XAL), Playa Cansa Burros, 2 km al S de la Mancha, 10 December 1985, G. Castillo-Campos 4489 (XAL); Alto Lucero de Gutiérrez Barrios, Estación Biológica El Morro de la Mancha (INIREB), 14 September 1986, D. H. Lorence 5080 (MEXU, XAL); Alvarado, Desembarcadero, 18 September 1957, F. Miranda 8519 (MEXU, XAL); Isla Verde, 17 July 1967, L. I. Nevling 54 (MEXU, XAL); Montepío, 14 km W de Catemaco, 31 August 1964, L. González Quintero 4534 (XAL); Nautla, a 11 km de Palma Sola, 12 December 1972, F. Chiang 324 (MEXU); Punta Limón, Transecto de P14 rumbo a Monte de Oro, 20 June 1972, A. Lot 1843 (MEXU); Reserva de Los Tuxtlas, Puntillas, 27 January 1968, M. Sousa 3401 (ENCB, MEXU); San Andrés Tuxtla, Poblado de Balzapote, 22 March 1986, D. H. Lorence 4974 (MEXU, XAL); Playa de Balzapote, 30 Septiember 1974, M. Sousa 4451 (MEXU), 8 February 1975, J. I. Calzada 11331 (MEXU, XAL); San Carlos, Lado E de Laguna Salada, 26 June 1976, J. Dorantes 1062 (MEXU); Tamiahua, Barra de Corazones, a 2 km de Paso Chorreras, 10 January 1982, S. Hernández 201 (MEXU); Tecolutla, 28 December 1969, W. Boege 1317 (MEXU); Tuxpan, Barra de Tuxpan, 31 October 1971, L. Monroy 157 (MEXU); Veracruz, Playa Norte de Veracruz en carretera a Cardel, 12 December 1980, J. Palma 383 (XAL). PANAMA, Cartí, El Llano to Cartí road, Between airport (coast) and Río Cartí Grande, 25 May 1985, G. C. de Nevers 5795 (MO).

4. Discussion

The interpretation of published names, particularly older names, in Randia aculeata is frequently challenging due to the absence of well-preserved specimen types, the geographic distribution range, and the lack of identification keys and taxonomic treatments. In the “Rubiaceas of Mexico”, R. tomatillo is treated as a synonym of R. aculeata var. dasyclada [6], a variety described in 1972 by Steyermark [22], based on the persistent hirtellous pubescence of the branches, in contrast to the glabrous branches of the typical variety (Randia aculeata var. aculeata).
Randia tomatillo is distinguished from many other Randia by its scandent habit, a growth form that offers several ecological advantages in coastal dune environments. This adaptation can be crucial in dynamic and often unstable dune systems, where vertical growth could be compromised by the prevalent strong and persistent winds [23]. Liana-like or scandent plants have many anatomical adaptations for flexibility and mechanical resilience [24,25]. In coastal dunes, the flexible growth habit could allow for withstanding the typical winds of these environments, reducing the risk of mechanical damage or uprooting. In contrast, R. aculeata and R. thurberi are more conventional in form, existing as treelets or typical shrubs. These growth forms are better suited to the relatively stable substrates of dry forests and other widespread environments, where structural rigidity is beneficial.
Another unique characteristic of R. tomatillo is the presence of leaf prisms, which are infrequent among most angiosperms but have been well documented in the Cactaceae family, and they are considered a highly valuable diagnostic character [26,27,28,29] and reported in other groups, such as Begonia L. [30]. Some studies speculate that the presence of epidermal prisms may offer an adaptive function by deterring herbivory [18,31,32]. It is plausible that the formation of these crystals in R. tomatillo may be a response to the coastal dune environment, where the specimens were collected, potentially contributing to environmental resilience or stress adaptation in this habitat.
To date, Randia tomatillo is apparently the only taxon in the genus completely adapted to water seed dispersion. Hydrochory is a form of seed dispersal that utilizes water currents to transport seeds away from the parent plant in environments dominated by water bodies, such as coastal areas [33]. The morphological and anatomical adaptations for this fruit dispersal mode include fruits with buoyant structures or tissues that allow them to float, such as air-filled cavities or fibrous husks, which facilitate movement across water surfaces [34,35]. An iconic example is the coconut (Cocos nucifera L., Arecaceae), whose fibrous husk provides both buoyancy and protection, enabling it to disperse across vast oceanic distances [36,37]. In R. tomatillo, the spongy pericarp presumably provides buoyancy and a durable barrier against saltwater, allowing the propagules to float and disperse with tidal movements. Without a doubt, the fruit dispersal mode in the genus Randia is a very interesting topic, since fleshy fruits are typically dispersed by birds or mammals, but in this case, there is a clear adaptation to the coastal environment; therefore, studies on morphology, anatomy, and ecology are needed for R. tomatillo and other species.
Randia aculeata is widely distributed across several regions in the Americas, from tropical North America (Florida) to northern South America (Colombia, Peru, and Venezuela) and the Antilles, indicating its ecological versatility and its taxonomic complexity. This species was originally described in 1753 by Linnaeus [38]; however, the locality of the original material was not specified. Given this, Steyermark designated a fruiting specimen from Jamaica in the Antilles as the neotype [22]. The significant morphological variation and the widespread distribution have led to it being viewed as a taxonomically challenging species, partly due to the incomplete material for identification, as flowers are rarely collected, and the pistillate flowers are almost never found, possibly because they are ephemeral.
An example of this variation is that some plants are spineless, which has led some authors to classify them as Randia mitis, although they generally appear to correspond more to a morphological variant than a distinct taxon.
According to many taxonomic treatments, there are at least eight names in the synonymy of R. aculeata [5,6], highlighting the complexity of circumscribing the species; thus, it is necessary to address this issue by exploring new sources of evidence and covering the species’ broad distribution.

5. Conclusions

The taxonomic evaluation of R. tomatillo underscores the importance of reassessing species boundaries within the R. aculeata complex. Our findings reveal that R. tomatillo can be distinguished by a combination of unique morphological and ecological traits, such as its scandent habit, spongy fruit pericarp, and prisms in the leaf mesophyll. These morphological features can be related to adaptations to coastal dune environments, suggesting an evolutionary divergence from related taxa. This study also highlights the significance of micromorphological characters, such as the presence and type of crystals, in resolving taxonomic challenges within Randia. This research not only clarifies the identity of R. tomatillo but also illustrates the need for integrative approaches to better understand the complex taxonomy of the genus Randia.

Author Contributions

Conceptualization, A.T.-M.; methodology, A.T.-M. and M.S.J.N.; investigation, A.T.-M. and M.S.J.N.; resources, A.T.-M.; writing—original draft preparation, A.T.-M.; writing—review and editing, A.T.-M. and M.S.J.N.; visualization, A.T.-M.; supervision, A.T.-M.; project administration, A.T.-M.; funding acquisition, A.T.-M. and M.S.J.N. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Programa de Apoyo a Proyectos de Investigación e Innovación Tecnológica-UNAM PAPIIT IA205224.

Data Availability Statement

No new data were created.

Acknowledgments

Special thanks to Alejandro de la Rosa Tilapa for their help on figure elaborations and MEB photographs. The authors thank Berenit Mendoza Garfias (IBUNAM) for her assistance with MEB photographs at IBUNAM. Special thanks to the herbarium curators and personal associates from MEXU, FESC, and XAL. We are grateful to the Programa de Apoyo a Proyectos de Investigación e Innovación Tecnológica-UNAM PAPIIT IA205224. Thanks to Eduardo Lazcano Flores for providing the herbarium material from Veracruz.

Conflicts of Interest

The authors declare no conflicts of interest.

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Figure 1. Randia tomatillo and morphologically related species. (A–D) Randia tomatillo. (A) Plant in sand dunes. (B) Scandent lifeform. (C) Flower. (D) Fruit. (E,F) Randia aculeata. (E) Shrub lifeform. (F) Fruit. (G,H) Randia thurberi. (G) Shrub lifeform. (H) Fruit. Photographs (A,B,D) by H. Bojorquez, (C) by Oscar Jimenez, (E) by Ignacio Saldaña, (F) by Alexis López, (G) by Jaime Briseño, and (H) by Raphael Forns.
Figure 1. Randia tomatillo and morphologically related species. (A–D) Randia tomatillo. (A) Plant in sand dunes. (B) Scandent lifeform. (C) Flower. (D) Fruit. (E,F) Randia aculeata. (E) Shrub lifeform. (F) Fruit. (G,H) Randia thurberi. (G) Shrub lifeform. (H) Fruit. Photographs (A,B,D) by H. Bojorquez, (C) by Oscar Jimenez, (E) by Ignacio Saldaña, (F) by Alexis López, (G) by Jaime Briseño, and (H) by Raphael Forns.
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Figure 2. Fruits: longitudinal view and tissue schemes. (A) Randia tomatillo spongy pericarp. (B) Randia aculeata sclerified pericarp. (C) Randia thurberi sclerified pericarp.
Figure 2. Fruits: longitudinal view and tissue schemes. (A) Randia tomatillo spongy pericarp. (B) Randia aculeata sclerified pericarp. (C) Randia thurberi sclerified pericarp.
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Figure 3. Presence of calcium oxalate crystals in a leaf. (A) Prisms of R. tomatillo (arrows). (B) Details of the prisms (yellow-colored). (C) Druses in R. aculeata (green-colored). (D) Druse in R. thurberi (green-colored).
Figure 3. Presence of calcium oxalate crystals in a leaf. (A) Prisms of R. tomatillo (arrows). (B) Details of the prisms (yellow-colored). (C) Druses in R. aculeata (green-colored). (D) Druse in R. thurberi (green-colored).
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Figure 4. Geographical distribution. (A) R. tomatillo (red circles). (B) R. aculeata (yellow circles) and R. thurberi (blue circles).
Figure 4. Geographical distribution. (A) R. tomatillo (red circles). (B) R. aculeata (yellow circles) and R. thurberi (blue circles).
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Table 1. Comparison of morphological characters and habitat of Randia tomatillo and morphologically related species.
Table 1. Comparison of morphological characters and habitat of Randia tomatillo and morphologically related species.
Character/TaxonR. tomatilloR. aculeataR. thurberi
LifeformScandent shrubsTreelets or shrubsTreelets or shrubs
Spines dispositionPairedPairedPaired
Spine length5–16 mm6–22 mm4–26 mm
Twig pubescenceHirtuloseGlabrate or puberulentGlabrate or puberulent
Leaf formNarrow to broadly obovate or obovate-elliptic, or rarely ovate or ovate-ellipticOvate, elliptic, subcircular, oblanceolate, narrow to broadly obovate, or obovate-ellipticOblanceolate, obovate, spatulate, or obcordate
Leaf size0.9–9.3 × 0.4–4.5 cm0.6–8.8 × 0.5–4.2 cm1–7.5 × 0.4–3.8 cm
Leaf textureCoriaceousPapyraceous to subcoriaceousPapyraceous
Leaf baseRounded, obtuse, acute, and attenuateCuneate, acute, truncate, or attenuateCuneate to acute, attenuate, and decurrent
Leaf apexObtuse or roundedAcute or obtuseObtuse, rounded, truncate, or emarginate
Leaf crystalsDruses and prismsDrusesDruses
Stipule persistenceDeciduousPersistentPersistent
Corolla tube length4–8 mm2–10 mm12–16 mm
Fruit formEllipsoidEllipsoid or spheroidalEllipsoid or spheroidal
Fruit size18–25 × 10–20 mm8–20 × 8–22 mm30–45 × 30–40 mm
Fruit pericarpSpongySclerifiedSclerified
Vegetation typeCoastal dunesCloud forest, Dry forest, Temperate forest, Tropical rainforest, and Xerophytic scrubDry forest
Geographical distributionMexico, Central America, and South America (Colombia)North America, Mexico, Central America, South America, and AntillesMexico and Central America
Examined specimensType: Mexico, Seler & Seler 4498 (GH, US). Calzada 11331 (MEXU, XAL), Castillo-Campos 4489 (XAL), Gonzalez-Quintero 4534 (MEXU), Lorence 4974 (MEXU, XAL),
Monroy 157 (MEXU), Palma 383 (XAL), Sinaca 1833 (XAL), Sousa 3401 (ENCB, MEXU).		Type: Jamaica, LINN 214.1 Ilustration [14]. Campos 6486 (MEXU, XAL), Croat and Hannon 63014 (MEXU), Martínez 23273 (MEXU), Nicholson 1892 (MEXU), Pringle 8068 (MEXU, XAL), Zamora 5393 (MEXU).Type: Mexico, Palmer 229 (GH, K, US) Albarrán 7 (FESC), Cedillo 2024 (ENCB, MEXU) Chiang 499 (XAL), Soto 16071 (MEXU, XAL).
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MDPI and ACS Style

Torres-Montúfar, A.; Jiménez Noriega, M.S. A Small Piece of a Complicated Puzzle: The Resurrection of Randia tomatillo Loes. from the Randia aculeata L. Complex (Rubiaceae). Taxonomy 2025, 5, 10. https://doi.org/10.3390/taxonomy5010010

AMA Style

Torres-Montúfar A, Jiménez Noriega MS. A Small Piece of a Complicated Puzzle: The Resurrection of Randia tomatillo Loes. from the Randia aculeata L. Complex (Rubiaceae). Taxonomy. 2025; 5(1):10. https://doi.org/10.3390/taxonomy5010010

Chicago/Turabian Style

Torres-Montúfar, Alejandro, and Mayte Stefany Jiménez Noriega. 2025. "A Small Piece of a Complicated Puzzle: The Resurrection of Randia tomatillo Loes. from the Randia aculeata L. Complex (Rubiaceae)" Taxonomy 5, no. 1: 10. https://doi.org/10.3390/taxonomy5010010

APA Style

Torres-Montúfar, A., & Jiménez Noriega, M. S. (2025). A Small Piece of a Complicated Puzzle: The Resurrection of Randia tomatillo Loes. from the Randia aculeata L. Complex (Rubiaceae). Taxonomy, 5(1), 10. https://doi.org/10.3390/taxonomy5010010

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