Sibon ayerbeorum VERA-PÉREZ, 2019
Can you confirm these amateur observations of Sibon ayerbeorum?
|Higher Taxa||Colubridae (Dipsadinae), Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes)|
|Common Names||E: Ayerbes’ snail-eater|
Spanish: Caracolera de los Ayerbe
|Synonym||Sibon ayerbeorum VERA-PÉREZ 2019|
Sibon cf. lamari — AYERBE et al. 2007
Type locality: sector La Cueva, Parque Nacional Natural Munchique, municipality of El Tambo, department of Cauca, Colombia (2°46’15.6’’ N, 76°58’48.6’’ W, 1135 m).
|Types||Holotype. MHNUC-He-Se-000659 (field number LVP 0379; Figs. 1A, 2A, 3B and 4C-D), adult female collected by Luis Enrique Vera Pérez on October 18, 2017.|
Paratypes (N=3). MHNUC-He-Se-000660 (field number LVP 0380; Figs. 1B, 2B, 3A, 4A-B and 5A), adult female collected by Luis Enrique Vera Pérez on October 19, 2017, at same locality as holotype (2o46’14.6’’ N, 76o58’44.3’’ W, 1191 m). MHNUC-He-Se-000360, 000361 (field numbers: CSA-00248-se, 00249-se), male and fe- male juveniles, respectively, collected on June 15–16, 1988, at San Joaquín River, La Playa, Parque Nacional Natu- ral Munchique, municipality of El Tambo, department of Cauca, Colombia (1400 m) by Óscar Mosca Castillo.
|Diagnosis||Diagnosis. Sibon ayerbeorum differs from all other congeners based on the following combination of characters: (1) 15–15–15 (N=3) or uncommonly 15–17–15 (N=1) smooth DSR without enlarged vertebral row; (2) preoculars absent; (3) non-protuberant eyes; (4) six supralabials with 3th to 5th (N=6) or 3th and 4th (N=2) contacting orbit; (5) six infralabials with 1st to 4th in contact with anterior chinshields, (6) first pair of infralabials generally in contact behind symphysial (N=3); (7) postmental absent; (8) 155 ventrals in the single male, 136–140 in females; (9) 93 paired subcauldals in the single male, 78–79 in females; (10) 248 ventrals plus subcaudals in the single male, 214–219 in females; (11) 15.6 mm SVL in the single male, 13.6–29.3 mm in females; (12) 6.5 mm TL in the single male, 5.9–12.4 mm in females; (13) body coloration pattern composed by irregular middorsal and ventrolateral dark-bordered ocelli; (14) ventral coloration dark with light spots in each ventral scale.|
Comparisons (Table 1 in Vera-Pérez 2019). Sibon ayerbeorum is more similar to species of the S. argus group, with which it shares an ocellate pattern, 15–15–15 DSR, loreal contacting eye, enlarged penultimate supralabial bordering the orbit and the ratio of tail length (28–33% of total length). However, it differs by having fewer ventrals, subcaudals, ventrals plus subcaudals and non-protuberant eyes with respect to S. argus (protuberant eyes); and fewer ventrals, subcaudals and ventrals plus subcaudals in the single male and females, only six supralabials, and postmental absent with respect to S. longifrenis (usually a tiny postmental). Additionally, it is smaller (maximum TOL=417 mm) than S. argus (more than 690 mm) and S. longifrenis (700 mm).
The new species can be easily differentiated from species of the S. annulatus and S. nebulatus groups because they present a regularly blotched/banded pattern or an irregular pattern with small blotches, spots, and stipples. In addition, the new species has fewer ventrals, supralabials, infralabials and an absence of postmental scales when compared with S. lamari. In relation to its congeners distributed in Colombia, S. ayerbeorum has fewer ventrals and subcaudals than S. annulatus; and fewer ventrals and ventrals plus subcaudals in males and females than S. nebulatus, as well as the absence of postmental scales (present in S. annulatus).
|Comment||Habitat: humid premontane forest and the transition toward tropical humid forest.|
Behavior: At type locality, individuals were found active at night (22:30, 23:30 h) moving on the ground (holotype) and foraging on vegetation about 1.5 m above ground (Fig. 4A in Vera-Pérez 2019). The defensive behavior upon the capture of paratype consisted of an expansion of head simulating a triangular shape, followed by a dorso-ventral compression and a body coiling forming a flattened dorsal posture (Fig. 4B). Then, it expelled foul odors by anal gland secretions and fecal wastes, and finally, it turned around to sit still in ventral position to look like a dead snake. During handling for taking pictures during the day, the holotype hid its head forming a “cinnamon roll” or body knot shape (Fig. 4C-D).
|Etymology||Named in honor of Santiago Ayerbe González and his sons Fernando and Santiago José (R.I.P). Dr. Ayerbe is a renowned Colombian pediatrician and toxinologist who has devoted most of his life in favor of prevention, treatment and management of snakebites, and has also contributed to the knowledge of the reptiles of the department of Cauca. Fernando is a renowned ornithologist and scientific illustrator, author of the most recent book about the birds of Colombia. Santiago José died in the earthquake which affected the city of Popayán in March, 1983.|