Liotyphlops palauophis, Marra Santos, 2023

Marra Santos, Fidelis Junio, 2023, A new species of the genus Liotyphlops Peters, 1881 (Serpentes, Anomalepididae) from Colombia and the synonymization of Liotyphlops beui (Amaral, 1924) with Liotyphlops ternetzii (Boulenger, 1896), ZooKeys 1146, pp. 87-114 : 87

Liotyphlops palauophis sp. nov.

Figs 1 , 2 , 3 , 4 , 5 , 6

Helminthophis anops Cope, 1899 (in part). Syntype of H. anops .

Type material.

Holotype. AMNH R-9550, 361 mm TL, Colombia, neighborhood of Bogota, 1899.

Diagnosis.

Liotyphlops palauophis sp. nov. is distinguished from all other Liotyphlops by having the frontal scale divided (vs single) and a central foramen in the parabasisphenoid (vs foramen absent). It is further distinguished from L. albirostris , L. argaleus , L. bondensis , L. caissara , L. haadi , L. trefauti , and L. wilderi in having two scales (vs one scale) contacting the posterior edge of the nasal between the second supralabial and prefrontal. It is further distinguished from L. beui , L. schubarti , L. taylori , and L. ternetzii by having four (vs three) scales contacting the posterior edge of the prefrontal. It is distinguished from L. anops by having 28/26/26 scales around the body and 19 subcaudal scales (vs 26/24/24 scales around the body and 12-14 subcaudal scales), and from L. sousai in having 573 dorsal scales and 561 ventral scales (vs 439 dorsal scales and 427 ventral scales).

Description.

Meristic data in Table 1 . Total length 361.2 mm, head length 5.3 mm (1.5% TL), snout-vent length 353 mm (97.7% TL), tail length 8.2 mm (2.3% TL), head width 3.8 mm (71.7% HL), and head height 3.1 mm (58.5% HL). Body covered with cycloid scales. Rostral scale large, longer than wide, contacting nasals anterolaterally, prefrontals laterally, and divided frontal posteriorly. Pair of triangular prefrontals bordered anterolaterally by rostral, ventrally by large divided nasal, and dorsoposteriorly by frontal. Posterior edge of prefrontals passing posterior edge of rostral. Frontal scale divided. Nasal scale divided and bordered anteriorly by rostral, dorsally by prefrontal, ventrally by first and second supralabials, and posteriorly by two scales that lie between prefrontal and second supralabial. Eye spot not visible. Four scales contacting posterior edge of prefrontal (three cycloid scales + frontal). Two scales contacting posterior edge of nasal between second supralabial and prefrontal. Six scales in first vertical row of dorsal scales. Mental triangular, not divided, wider than long, contacting first infralabials. Supralabials four, infralabials three. Scales around body 28/26/26. Dorsal scales 573, vental scales 561, and subcaudal scales 19.

Description of skull.

High-resolution x-ray computed tomography of skull bones in Figs 3 - 5 . Main body of premaxilla on ventral surface of snout. Maxilla-premaxilla contact widely separated. Lateral maxillary foramina absent. Maxilla alveolar row oriented transversely. Nasal fused. Nasal-frontal boundary convex posteriorly in a shallow W-shaped suture. Prefrontal separated from nasal. Prefrontal moveably articulated to frontal. Postorbital element present. Posterior orbital margin incomplete. Frontals gradually tapering anteriorly. Frontal paired. Frontal-parietal contact (dorsal aspect) mostly straight and transverse, median notch in frontals slight at most. Parietal paired. Posterior border of parietal without median projection over supraoccipital. Supratemporal present. Posteromedial flange of septomaxilla short, not contacting frontal. Septomaxilla with lateral flange contributing to posterior border of external naris. Fenestra for duct of Jacobson’s organ posteroventrally positioned. Palatine not in contact with vomer, maxilla, or pterygoid. Central foramen present in parabasisphenoid. Ectopterygoid present. Supraoccipital present and single not participating in internal sidewall of neurocranium. External surface (dorsoposterior) of supraoccipital without transverse ridge. Supraoccipital-prootic contact narrow, less than half supraoccipital-parietal contact. Splenial not present as discrete element. Coronoid and angular separated by prearticular portion of compound bone. Retroarticular process long, longer than articular facet. Teeth present in maxilla, but lacking in dentary, premaxilla, palatine, and pterygoid.

Coloration in alcohol.

Dorsal and ventral body pale cream with brown pigmentation points along dorsal region of body.

Distribution.

Known only from the type locality in the neighborhood of Bogota, Colombia (Fig. 6 ), according to the information provided by Cope (1899).

Etymology.

The species name is in honor of Alfredo Palau Peña (June 10, 1969-August 8, 2020), a Brazilian herpetologist and my friend, who was killed by the COVID-19 virus. A combination of his name Palau and the Greek ophis, meaning snake.

Figures

Figure 1. Holotype of Liotyphlops palauophis sp. nov., AMNH R- 9550, 361.2 mm TL, Colombia, neighborhood of Bogota. Scale bar: 5 mm.

Figure 2. Dorsal (top), lateral (center), and ventral (bottom) views of the head of Liotyphlops palauophis sp. nov., AMNH R- 9550, holotype. Scale bar: 1 mm.

Figure 3. Three-dimensional reconstruction of the skull of Liotyphlops palauophis sp. nov., AMNH R- 9550, holotype, based on HRXCT data. A lateral view B dorsal view C ventral view with lower jaw partially digitally removed D anterior view E posterior view. Scale bar: 1 mm. Anatomical abbreviations: a: angular; bo: basioccipital; cb: compound bone; co: coronoid; d: dentary; ec: ectopterygoid; en: external naris; f: frontal; fo: foramen; fv: fenestra vomeronasalis; m: maxilla; mf: mental foramen; n: nasal; oc: occipital condyle; ooc: otico-occipital (fused prootic + opisthotic + exoccipital); p: parietal; pa: palatine; pbs: parabasisphenoid; pe: postorbital element; pf: prefrontal; pg: pterygoid; pm: premaxilla; q: quadrate; rp: retroarticular process; sf: surangular foramen; sm: septomaxilla; st: supratemporal; so: supraoccipital; tf: trigeminal foramen; v: vomer; vf: vomerine foramen.

Figure 4. Three-dimensional reconstruction of the skull of Liotyphlops palauophis sp. nov., AMNH R- 9550, holotype, based on HRXCT data. A transversal view B frontal view C sagittal view. Scale bar: 1 mm. Anatomical abbreviations: a: angular; an: acoustic nerve foramen; bo: basioccipital; cb: compound bone; cbp: compound bone prearticular component; cbs: compound bone surangular component; ci: conchal invagination; co: coronoid; cv: cavum vestibuli; d: dentary; dp: descensus parietalis; ec: ectopterygoid; en: external naris; f: frontal; fl: frontal laterally descending flange; fo: foramen; fpb: facial nerve palatine branch foramen; fs: frontal subolfactory process; fv: fenestra vomeronasalis; m: maxilla; Mc: Meckel's canal; mf: mental foramen; n: nasal; nl: nasal lateral flange; ns: medial nasal septum; oc: occipital condyle; on: optic nerve foramen; ooc: otico-occipital (fused prootic + opisthotic + exoccipital); p: parietal; pa: palatine; pbc: parabasal (Vidian) canal; pbs: parabasisphenoid; pe: postorbital element; pf: prefrontal; pg: pterygoid; pm: premaxilla; pvs: posterior vertical semicircular canal; q: quadrate; rp: retroarticular process; rstm: recessus scalae tympani medial aperture; s: stapes; sf: surangular foramen; sm: septomaxilla; sml: septomaxilla lateral flange; st: supratemporal; so: supraoccipital; tf: trigeminal foramen; trc: trigeminofacialis chamber; v: vomer; vc: vomeronasal cupola; vf: vomerine foramen; vn: vomeronasal nerve passage.

Figure 5. Three-dimensional reconstruction of the lower jaw of Liotyphlops palauophis sp. nov., AMNH R- 9550, holotype, based on HRXCT data. A lateral view B medial view C dorsal view D ventral view E anterior view F posterior view. Scale bar: 1 mm. Anatomical abbreviations: a: angular; arf: articular fossa; cb: compound bone; cbp: compound bone prearticular component; cbs: compound bone surangular component; co: coronoid; d: dentary; Mc: Meckel's canal; mf: mental foramen; rp: retroarticular process; sf: surangular foramen.

Figure 6. Location of the holotype of Liotyphlops palauophis sp. nov. (black star), lectotype of Liotyphlops anops (white dot), and specimens of L. anops examined in this study (green dot).? = lack of detailed information about the type locality of L. palauophis sp. nov. and L. anops. This locality is based on information provided by Cope (1899).