[Herpetology • 2025] Rhinatrema koki • Re-diagnoses of rhinatrematid genera and description of A New Species of Guyanese Rhinatrema Duméril & Bibron, 1841 (Gymnophiona: Rhinatrematidae)

 

 Rhinatrema koki

Wilkinson & Bittencourt-Silva, 2025 

DOI: doi.org/10.25225/jvb.25060

Abstract

We describe a new species of the rhinatrematid caecilian genus Rhinatrema Duméril & Bibron, 1841 from Guyana based on a single specimen previously confused with the type species of Rhinatrema, R. bivittatum (Guérin-Méneville, 1838), and the more recently described Guyanese endemic R. shiv Gower, Wilkinson, Sherratt & Kok, 2010. The new species is distinctive in external morphology (a substantial pale dorsal head spot, no substantial pale dorsal tail spot), cranial osteology (many more inner than outer mandibular teeth) and mitochondrial DNA sequence data. We propose revised morphological diagnoses for the constituent genera as part of a brief systematic overview of the Rhinatrematidae Nussbaum, 1977, provide a key to the species of Rhinatrema, and present improved images of the cranial osteology of R. shiv.

 

KEYWORDS: Caecilian, computed tomography, Herpetology, Neotropics, systematics, taxonomy

Systematics

Rhinatrematidae Nussbaum, 1977

Type genus: Rhinatrema Duméril & Bibron, 1841.

Diagnosis: The only caecilians with the paired m. adductores mandibulae externi extending through the upper temporal fenestra to the mid-dorsum of the cranium.

Phylogenetic definition: All caecilians more closely related to R. bivittatum than to Caecilia tentaculata.

Distribution: Northern South America.

Content: three genera, 15 species. Amazops Wilkinson, Reynolds & Jacobs, 2021; Epicrionops Boulenger, 1883a; Rhinatrema Duméril & Bibron, 1841

Rhinatrema Duméril & Bibron, 1841

Diagnosis: Rhinatrematid caecilians with fangs (enlarged maxillary and outer mandibular teeth) and the orbit entirely within the maxillopalatine.

Phylogenetic definition: All caecilians more closely related to R. bivittatum than to A. amazops or E. bicolor.

Distribution: Brazil, French Guiana, Guyana, Suriname, Venezuela.

Content: seven species (bivittatum, gilbertogili, koki sp. nov., nigrum, shiv, ron, uaiuai).

USNM 566004, holotype of Rhinatrema koki sp. nov. with head end (top), whole body (middle) and tail end (bottom). Scale bar gradations in mm.

Photo by Harry Taylor (Natural History Museum, London).

Rhinatrema koki sp. nov.,  

Rhinatrema bivittatum Frost et al. (2006)

Rhinatrema shiv Cole et al. (2013)

 

Diagnosis: A Rhinatrema with a substantial pale dorsal head spot, no substantial pale dorsal tail spot and many more inner than outer mandibular teeth.

Etymology: The species is named in honour of Philippe J.R. Kok in recognition of his outstanding scholarship and scientific endeavours that have led to substantial and important contributions to the herpetology of the Guyana Shield. The specific epithet is a noun in the genitive case, but for nomenclatural purposes is considered a noun in apposition. Borrowing from the French, we suggest the vernacular ‘Kok’s Rhinatrème’.

Mark Wilkinson and Gabriela B. Bittencourt-Silva. 2025. Re-diagnoses of rhinatrematid genera and description of A New Species of Guyanese Rhinatrema Duméril & Bibron, 1841 (Amphibia: Gymnophiona: Rhinatrematidae). J. of Vertebrate Biology. 74(25060):25060.1-16. DOI: doi.org/10.25225/jvb.25060 [2 September 2025]

 

[Mammalogy • 2017] Sylvilagus parentum • A New Species of Cottontail Rabbit (Lagomorpha: Leporidae: Sylvilagus) from Suriname, with Comments on the Taxonomy of Allied Taxa from northern South America

DOI:  10.1093/jmammal/gyx048/3828752

noticias.uol.com.br

Abstract

Of the 19 currently recognized species of Sylvilagus Gray, 1867, 15 inhabit North America, and only 5 are recognized in South America: S. brasiliensis Linnaeus, 1758 (throughout most of the continent); S. varynaensis Durant and Guevara, 2001, restricted to the southern lowlands of Venezuela (states of Barinas, Portuguesa, and Guarico); S. andinus (Thomas, 1897) from the Andean páramos of Ecuador and potentially in a sporadic manner to the Colombian and Venezuelan páramos; and S. tapetillus Thomas, 1913, from the coastal plain in the region of Rio de Janeiro. In addition to these, putative subspecies of S. floridanus, primarily a North American taxon, nominally are recognized from the grassland plains areas of northwestern South America east of the Andes. While S. varynaensis and S. tapetillus are monotypic, S. brasiliensis contains at least 37 named taxa in synonymy, distributed in various habitats; S. andinus requires further study. As a result of the recent description of a neotype for S. brasiliensis, it is now possible to assess species limits and begin the process of illuminating formerly obscured biological diversity in South American cottontails. Here, I describe a new species of Sylvilagus from the lowlands of western Suriname, and excise S. sanctaemartae Hershkovitz, 1950 from synonymy with S. brasiliensis. 

 Keywords: biodiversity, center of endemism, Colombia, conservation, Guiana Refuge, Guyana Area of Endemism, Guyana Shield, Neotropics, Sierra Nevada de Santa Marta

  External appearance of the species under consideration herein. Dorsal and ventral views of (left to right) Sylvilagus parentum, RMNH 31149, ♀, holotype; S. sanctaemartae, USNM 279993, ♀, holotype; S. brasiliensis, UFPE 1740, ♂, neotype. 

DOI:  10.1093/jmammal/gyx048/3828752/ 

Sylvilagus parentum, species nova 

Suriname Lowland Forest Cottontail, bakrakondre konkoni, langa jesi konkoni

Lepus brasiliensis Linnaeus, 1758:58. Part. 

Type locality: “America meridionali” [South America] 

Sylvilagus brasiliensis Hoogmoed, 1983:35. Part, not Linnaeus, 1758. Hoogmoed (1983:41) noted that “… ik het niet gewaagd om de Surinaamse konijnen tot een bepaalde subspecies te rekenen.” [I have not dared to assign the Surinamese rabbits to a particular subspecies [of S. brasiliensis].]

Etymology.— Genitive plural of the Latin noun parens, for my parents, Patricio Ruedas Younger (11 January 1931–22 February 2014) and Paloma Martín Daza (b. 25 January 1937), who supported me in so many ways during my life. Ordinarily, I prefer indigenous names; however, in the present instance, there are none such (E. B. Carlin, Section of Languages and Cultures of Native America, Leiden University Centre for Linguistics, in litt.). The Maroon name is konkoni, a name clearly derived from the Dutch “konijn,” and a term also applied to the agouti, Dasyprocta sp. (D. cristata, of uncertain taxonomic status, and D. leporina both occur in the region), hence lacking in information content.

Luis A. Ruedas. 2017. A New Species of Cottontail Rabbit (Lagomorpha: Leporidae: Sylvilagus) from Suriname, with Comments on the Taxonomy of Allied Taxa from northern South America.  Journal of Mammalogy. gyx048. DOI:  10.1093/jmammal/gyx048/3828752

Nova espécie de coelho sul-americano é descoberta por cientistas...

https://noticias.uol.com.br/ciencia/ultimas-noticias/redacao/2017/05/19/nova-especie-de-coelho-sul-americano-e-descoberta-por-cientistas.htm

De las 19 especies de conejos actualmente reconocidas en el género Sylvilagus Gray, 1867, 15 habitan Norteamérica mientras que solo cinco se conocen de Suramérica. Estas son S. brasiliensis Linnaeus, 1758 (en la mayor parte de la región), S. varynaensis Durant y Guevara, 2001 (restringido a las llanuras del sur de Venezuela, en los estados de Barinas, Portuguesa y Guarico), S. andinus (Thomas, 1897) de los páramos andinos de Ecuador y esporádicamente hasta los páramos de Colombia y Venezuela, y S. tapetillus Thomas, 1913, de las planicies costeras en la región de Rio de Janeiro. Además de estas cuatro especies, se reconoce de forma nominal en las llanuras y pastizales del noroeste de Suramérica, al este de los Andes, a supuestas subespecies de S. floridanus, una especie mayormente norteamericana. Aunque S. varynaensis y S. tapetillus son monotípicas, S. brasiliensis en cambio comprende por lo menos 37 taxones en su sinonimia, distribuidos en numerosos y variados ambientes; se desconoce aún la taxonomía de S. andinus. Uno de los resultados de la reciente descripción de un neotipo para S. brasiliensis es que ahora es posible llevar a cabo una delimitación más certera de las especies de Sylvilagus en Suramérica. Con esto se puede así iniciar un proceso de descubrimiento de la diversidad biológica regional en el género, diversidad previamente entenebrecida. En el presente trabajo describo una nueva especie de Sylvilagus de las llanuras del oeste de Surinam, y extraigo a S. sanctaemartae Hershkovitz, 1950 de su sinonimia con S. brasiliensis.

[Botany • 2017] A Revision and Recircumscription of Begonia Section Pilderia including One New Species, Begonia tepuiensis

Begonia tepuiensis Moonlight & Jara  

DOI: 10.11646/phytotaxa.307.1.1 

Abstract

Novel phylogenetic data is used to show that the poorly-known species Begonia glandulifera and Begonia mariannensis form a clade with Begonia buddleiifolia, the type species of Begonia section Pilderia. A unique combination of characters is identified in this group and used to re-circumscribe the section to include these species, and two morphologically similar species: Begonia jenmanii, and Begonia humilliana. A new species is described herein as Begonia tepuiensis sp. nov. from a single tepui in the Amazonas State of Venezuela. A full taxonomic revision and key to the species of Begonia section Pilderia is presented and we assign all species to IUCN Red List categories.

Keywords: Andes, Begonia section Pilderia, Neotropics, Phylogeny, Guyana Shield, Trinidad and Tobago, Eudicots

Begonia section Pilderia (Klotzsch) A.DC. 

 Distribution:— Colombia, Ecuador, Guyana, Perú, Trinidad and Tobago, Venezuela. 

1. Begonia buddleiifolia A.DC. (1859)

2. Begonia glandulifera Griseb. (1860) 

3. Begonia humillima L.B.Sm. & Wassh. (1973)  

4. Begonia jenmanii Tutin (1940) 

5. Begonia mariannensis Wassh. & T. McClellan (1995) 

6. Begonia tepuiensis Moonlight & Jara spec. nov.

Etymology:— The genus Begonia is relatively poorly known from the tepuis of northern Amazonia. We name this species B. tepuiensis as it is only the third Begonia species described exclusively from tepuis after B. steyermarkii L.B.Sm. & B.G.Schub and B. nubicola L.B.Sm. & B.G.Schub.

FIGURE 6. Begonia tepuiensis Moonlight & Jara. 
A. Habit, flowering top; B. Habit, shoot with rooting nodes; C. Female flower (side view); D. Stigma (front view); E. Stigma (back view); F. Bract; G. Detail of leaf hairs, upper lamina; H. Detail of leaf hairs, lower lamina. 

Drawn from type collection R.S. Cowen & J.J. Wurdack 31443 by Claire Banks. 

twitter.com/PeterMoonlight

P.W. Moonlight and A. Jara-Muñoz. 2017. A Revision and Recircumscription of Begonia Section Pilderia including One New Species. Phytotaxa. 307(1); 1-22.  DOI: 10.11646/phytotaxa.307.1.1.

twitter.com/PeterMoonlight/status/865465112059977728

Resumen: Se usaron nuevos datos filogenéticos para mostrar que las especies pobremente conocidas: Begonia glandulifera y Begonia mariannensis forman un clado con Begonia buddleiifolia, la especie tipo de Begonia sección Pilderia. Se identificaron una combinación única de caracteres en este grupo, que fueron usados para re-circunscribir la sección incluyendo estas especies, y dos especies morfológicamente similares: Begonia jenmanii y Begonia humilliana. Se describe una nueva especie, Begonia tepuiensis sp. nov. de un tepui en el estado Amazonas de Venezuela. Se presenta también una revisión taxonómica completa y una clave para las especies de Begonia sección Pilderia y asignamos todas las especies a categorías de la Lista Roja de la UICN.