![]() |
Nymphargus colomai Guayasamin et Hutter Nymphargus humboldti Guayasamin, Cisneros-Heredia, McDiarmid et Hutter
Nymphargus lindae Guayasamin
in Guayasamin, Cisneros-Heredia, McDiarmid, Peña & Hutter, 2020. |
Abstract
Glassfrogs (family: Centrolenidae) represent a fantastic radiation (~150 described species) of Neotropical anurans that originated in South America and dispersed into Central America. In this study, we review the systematics of Ecuadorian glassfrogs, providing species accounts of all 60 species, including three new species described herein. For all Ecuadorian species, we provide new information on the evolution, morphology, biology, conservation, and distribution. We present a new molecular phylogeny for Centrolenidae and address cryptic diversity within the family. We employ a candidate species system and designate 24 putative new species that require further study to determine their species status. We find that, in some cases, currently recognized species lack justification; specifically, we place Centrolene gemmata and Centrolene scirtetes under the synonymy of Centrolene lynchi; C. guanacarum and C. bacata under the synonymy of Centrolene sanchezi; Cochranella phryxa under the synonymy of Cochranella resplendens; and Hyalinobatrachium ruedai under the synonymy of Hyalinobatrachium munozorum. We also find that diversification patterns are mostly congruent with allopatric speciation, facilitated by barriers to gene flow (e.g., valleys, mountains, linearity of the Andes), and that niche conservatism is a dominant feature in the family. Conservation threats are diverse, but habitat destruction and climate change are of particular concern. The most imperiled glassfrogs in Ecuador are Centrolene buckleyi, C. charapita, C. geckoidea, C. medemi, C. pipilata, Cochranella mache, Nymphargus balionotus, N. manduriacu, N. megacheirus, and N. sucre, all of which are considered Critically Endangered. Lastly, we identify priority areas for glassfrog conservation in Ecuador.
Keywords: anura; biogeography; centrolenidae; systematics; taxonomy
![]() |
| Figure 5. Parental care in glassfrogs. Adult male of Hyalinobatrachium aureoguttatum, with egg clutch. Photo by Luis A. Coloma. |
![]() |
| Figure 1. Relationships among glassfrog genera as inferred herein, using maximum likelihood criterium. Taxonomy sensu Guayasamin et al. [2009]. Taxon sampling includes 113 named glassfrog species, 24 putative new species, and 49 outgroup taxa (not shown). The dataset contains complete or partial sequences of 10 genes representing 6513 bp of data (mitochondrial: 12S rRNA, 16S rRNA, ND1; nuclear: BDNF, C-MYC exon 2, CXCR4, NCX1, POMC, RAG1, SLC8A3). Sequences were generated in previous studies, as well as this one (see Table S2). Relationships within each genus are shown in additional figures and follow the same methodology. |
![]()
![]() |
Figure 2. Dorsal color patterns in glassfrogs.
(A) Uniform; Sachatamia ilex, QCAZ 47193. (B) With small and well-defined yellow spots;Nymphargus humboldti sp. nov., QCAZ 41084. (C) With small and diffuse yellow spots; Hyalinobatrachium fleischmanni, QCAZ 45386. (D) With large yellow spots; H. aureoguttatum, QCAZ 45365. (E) With small ocelli, N. cochranae, QCAZ 31113. (F) With ocelli and dark flecks; N. anomalus, QCAZ 47507. (G) With irregular light-green marks and small well-defined black spots, H. iaspidiense, QCAZ 38438. (H) With green reticulation; H. cf. valerioi, ZSFQ 0544 (photo by Jose Vieira).
All photographs by Luis A. Coloma, except when noted. |
![]() |
Figure 34. Centrolene geckoidea in life. Ecuador, Carchi province, Río La Plata (...; 2525 m), on the Maldonado–Tulcán road, DHMECN 0900.
Photo by Doug Wechsler (25 July 1988). |
Centrolene geckoidea Jiménez de la Espada 1872
Centrolene geckoideum Jiménez de la Espada, 1872.
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.
![]() |
Figure 145. Nymphargus colomai sp. nov. in life from stream nearby Miazi Alto, Zamora Chinchipe province, Ecuador.
Top left: QCAZ 41590, holotype; other frogs are part of the type series.
Photos by Holger Braun and Juan M. Guayasamin |
Nymphargus colomai new species Guayasamin and Hutter
Common names: English: Coloma’s Glassfrog.
Spanish: Rana de Cristal de Coloma.
Diagnosis: (1) Dentigerous process of the vomer lacking teeth or with few teeth (up to 3); (2) snout truncated to slightly protruding in lateral profile; truncated in dorsal view; (3) tympanum oriented almost vertically, with slight lateral and posterior inclinations, its diameter about 23%–27% of eye diameter; upper half of tympanic annulus obscured by supratympanic fold and warts; tympanic membrane pigmented as surrounding skin; (4) dorsal skin shagreen, with numerous spiculated warts and spicules in males; females unknown; (5) venter areolate; pair of enlarged subcloacal warts; (6) white parietal peritoneum covering about anterior half of venter (condition P2); white pericardium; translucent peritonea on kidneys, intestines, stomach, gall and urinary bladders (condition V1); (7) liver lobate, covered by translucent peritoneum (condition H0); (8) humeral spines absent; (9) webbing absent between Fingers I, II, and III, absent or basal between Fingers III and IV; webbing formula III (23/4–3) — (21/2–22/3) IV; (10) feet about two-thirds webbed; webbing formula: I 2− — 21/3 II (1+–11/3) — 21/2 III 11/2 — (22/3–23/4) IV 3– — (11/2 – 2–) V; (11) ulnar and tarsal folds present, low; (12) concealed prepollex; in males, nuptial pad Type I; (13) Finger II slightly longer than Finger I; (14) disc of Finger III width about 46%–50% of eye diameter; (15) in life, dorsum varies from dull yellowish green to tangerine yellow, brown, or grey olive with numerous small yellow to orange spots; bones green; (16) in preservative, dorsum grey to greyish lavender with numerous unpigmented spots; (17) in life, iris silvery white with slight yellow hue and a clearly marked horizontal black stripe; (18) melanophores on dorsal surfaces of Fingers III and IV and Toes IV and V; (19) males call from the upper surfaces of leaves; call unknown; (20) fighting behavior unknown; (21) egg deposition site unknown; parental care unknown; (22) tadpole unknown; (23) small body size; in males, SVL 25.0– 25.7 mm (n = 3); females unknown.
Etymology: The specific name is a patronym for Luis A. Coloma in recognition of his pioneer and continual efforts in studying and protecting amphibians, as well as mentoring numerous students, including Juan M. Guayasamin. Luis Coloma is the Director of the Jambatu Center for Research and Conservation of Amphibians (Centro Jambatu de Investigación y Conservación de Anfibios; see http://www.anfibiosecuador.ec/). The Jambatu Center houses dozens of critically endangered amphibians, in an outstanding effort to conserve frogs and toads. Luis received the Sabin Award for Amphibian Conservation in 2007 (http://www.amphibians.org/grants/sabin-award/).
![]() |
Figure 158. Nymphargus humboldti sp. nov. in life. Male from Río Yana Challuwa, Pastaza province, Ecuador, QCAZ 47514, paratype.
Photos by Luis A. Coloma. |
Nymphargus humboldti new species Guayasamin, Cisneros-Heredia, McDiarmid and Hutter
Common names: English: Humboldt’s Glassfrog.
Spanish: Rana de cristal de Humboldt.
Diagnosis: (1) Vomers with edentate dentigerous process; (2) snout truncated to bluntly rounded in lateral profile; truncated in dorsal view; (3) tympanum oriented almost vertically, with slight lateral and posterior inclinations, its diameter about 20%–27% of eye diameter; upper fourth of tympanic annulus obscured by supratympanic fold; tympanic membrane pigmented as surrounding skin; (4) dorsal skin shagreen, with minute spicules in males; (5) venter areolate; pair of enlarged subcloacal warts; (6) white parietal peritoneum covering anterior 50%–60% of venter (condition P2); white pericardium; translucent peritonea covering intestines, stomach, kidneys, gall and urinary bladders (condition V1); (7) liver tetralobed, covered by transparent peritoneum (condition H0); (8) humeral spines absent; (9) webbing absent between inner fingers, absent or basal between Fingers III and IV; webbing formula III (3––3) — (22/3–3–) IV; (10) feet about two-thirds webbed; webbing formula: I (2−–2) — (2+–21/4)II (1+–11/2) — (2+–21/2) III (1+–11/4) — (21/4–3+)IV (21/2–3–) — (12/3–2−) V; (11) ulnar and tarsal folds present, low; (12) concealed prepollex; in males, nuptial pad Type I; (13) Finger I about same length as Finger II (Finger I length 94%–102% of Finger II); (14) disc width of Finger III about 50%–55% of eye diameter; (15) in life, dorsum green with yellow spots (Figure 158); bones green; (16) in preservative, dorsum lavender with small white spots; (18) melanophores usually lacking from dorsal surfaces of fingers and toes, except for few on Toe V; (19) males call from upper surfaces of leaves; call unknown; (20) fighting behavior unknown; (21) egg deposition site unknown; parental care unknown; (22) tadpoles unknown; (23) small body size; in males, SVL 23.3–25.2 mm ( = 24.3 ± 0.684, n = 13); in females, SVL 25.5–27.4 mm (n = 3).
Etymology: The specific epithet humboldti honors Alexander von Humboldt for his unparalleled contributions to biogeography, integrative perspective of the sciences and arts, humanism, and also for his devotion towards mountains.
![]() |
Figure 165. Nymphargus lindae sp. nov. in life, Adult female, paratype, QCAZ 41597.
Photo taken at the type locality by Juan M. Guayasamin. |
Nymphargus lindae new species Guayasamin
Common names: English: Linda’s Glassfrog.
Spanish: Rana de Cristal de Linda.
Diagnosis: (1) Dentigerous process of the vomer with two to four teeth; (2) snout truncated to bluntly rounded in lateral profile; truncated in dorsal view; (3) tympanum oriented almost vertically, with slight lateral and posterior inclinations, its diameter about 20%–26% of eye diameter; upper fourth of tympanic annulus obscured by supratympanic fold; tympanic membrane pigmented as surrounding skin; (4) dorsal skin shagreen, with minute spicules in males; (5) venter areolate; pair of enlarged subcloacal warts; (6) white parietal peritoneum covering about anterior 60% of venter (condition P3); white pericardium; translucent peritonea covering intestines, stomach, kidneys, gall and urinary bladders (condition V1); (7) liver tetralobed, covered by transparent peritoneum (condition H0); (8) humeral spines absent; (9) webbing absent between inner fingers, absent or basal between Fingers III and IV (Figure 165); webbing formula III (24/5–3−) — (23/4–3−) IV; (10) feet about two-thirds webbed (Figure 165); webbing formula: I 2− — (21/4–21/3)II (11/4–11/3) — (21/4–21/3) III (11/4–11/3) — (22/3–3−)IV (2–2+) — 2−V; (11) ulnar and tarsal folds present, low; (12) concealed prepollex; in males, nuptial pad Type I; (13) Finger I about same length as Finger II or slightly shorter (Finger I length 94%–100% of Finger II); (14) disc of Finger III width about 46%–50% of eye diameter; (15) in life, dorsum green with dark lavender to black ocelli enclosing yellow to orange spots (Figure 165); bones green; (16) in preservative, dorsum lavender with black ocelli with white centers; (17) iris white with slight pale yellow hue and thin black reticulation; (18) melanophores usually lacking from dorsal surfaces of fingers and toes, except for few on Toe V; (19) males call from the upper surfaces of leaves; call unknown; (20) fighting behavior unknown; (21) egg deposition site unknown; parental care unknown; (22) tadpoles unknown; (23) small to medium body size; in males, SVL 23.0–26.3 mm ( = 25.1 ± 0.848, n = 12); in females, SVL 27.2–27.8 mm (n = 2).
Etymology: The specific epithet honors Linda Trueb, one of the most influential amphibian systematist of our days. Linda, as the curator of the herpetological collection of the University of Kansas, has led one of the most prolific and solid research group on amphibian biology, mentoring numerous students (including JMG). Her work on the evolution of skeletal diversity, ontogeny, and scientific illustration is outstanding.
![]() |
Figure 174. Nymphargus megacheirus in life. Adult male, holotype, KU 143245.
Photo by W. E. Duellman |
Nymphargus megacheirus (Lynch and Duellman, 1973).
Centrolenella megacheira Lynch and Duellman, 1973
Common names: English: Large-handed Glassfrog.
Spanish: Rana de Cristal de manos grandes.
Etymology: The specific epithet is from the Greek words megas, meaning large, and cheiros, meaning hand; the name is used to refer to the exceedingly large hands of the species.
Juan M. Guayasamin, Diego F. Cisneros-Heredia, Roy W. McDiarmid, Paula Peña and Carl R. Hutter. 2020. Glassfrogs of Ecuador: Diversity, Evolution, and Conservation.
Diversity. 12(6); 222. DOI:
10.3390/d12060222 (Special Issue: Systematics and Conservation of Neotropical Amphibians and Reptiles)
