Wednesday, February 12, 2020

[Herpetology • 2018] Rhadinella xerophila • A New Species of Rhadinella (Serpentes: Dipsadidae) from the Dry Forest of Motagua Valley, Guatemala

 Rhadinella xerophila 
Ariano-Sánchez & Campbell, 2018

We describe a new species of Rhadinella from the dry forest and thorn scrub of Valle del Motagua, Guatemala, a region and habitat where the congeners were previously unrecorded. This species is related to the group of Rhadinella that have dark dorsal coloration, which mostly or completely obscures a pattern of longitudinal striping characteristic of the majority of species of Rhadinella. The new species has dark gray, almost black, dorsal coloration with barely discernible slightly darker striping. Top of the head is mostly blackish with irregular auburn-orange markings on the internasals, prefrontals, frontal, parietals, loreals, postoculars, temporals, and two ultimate supralabials. Most conspicuous features are an orange-auburn Y-shaped marking along frontal-parietal and interparietal sutures, followed by an orange nuchal collar. The closest relative of the new species, based on morphological similarities, appears to be Rhadinella pilonaorum, which occurs in a relatively mesic habitat of pine-oak forest located about 90 km southwest from the type-locality of the new species.

Key words: Rhadinaea godmani species group, Rhadinella pilonaorum, color pattern, lepidosis, restrict endemism 

FIGURE 1. General view in life of the holotype of Rhadinella xerophila (UVG R-7003), SVL 214 mm (A) and landscape view of the dry forest habitat at Heloderma Natural Reserve, Motagua Valley (B). Photo "A" by A. Novales.

Rhadinella xerophila sp. nov. 

Etymology. The specific name is a feminine noun in apposition from the Greek ξηρός (xeros), meaning dry and the Latin phila, meaning loving, in reference to its characteristic of being the sole known member of Rhadinella that inhabits in forest experiencing the harsh and extended dry season characterizing the Motagua Valley. It also represents the urgent need that people and governments take the dry forest seriously as a biodiversity relevant forest that deserves the same levels of protection and love as other more known and charismatic forests such as rainforest.

Daniel Ariano-Sánchez and Jonathan A Campbell. 2018. A New Species of Rhadinella (Serpentes: Dipsadidae) from the Dry Forest of Motagua Valley, Guatemala. Zootaxa. 4442(2); DOI:  10.11646/zootaxa.4442.2.10