Conopsis nasus (GÜNTHER, 1858)
Can you confirm these amateur observations of Conopsis nasus?
|Higher Taxa||Colubridae, Colubrinae, Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes)|
|Subspecies||Conopsis nasus nasus GÜNTHER 1858|
Conopsis nasus labialis TANNER 1961
|Common Names||Largenose Earth Snake|
|Synonym||Conophis nasus GÜNTHER 1858: 6|
Oxyrhina (Exorhina) maculata JAN 1862 :54
Oxyrhina maculata anomala DUGÈS 1869:144
Conophis nasus — COPE 1879: 265
Conopsis maculatus COPE 1884:162
Ficimia nasus — GARMAN 1884: 83
Ficimia maculata — GARMAN 1884: 84
Contia nasus BOULENGER 1894: 268–269
Conopsis [nasus nasus] CUESTA TERRÓN 1930:176
Conopsis nasus heliae CUESTA TERRÓN 1930:175–176
Conopsis nasus labialis TANNER 1961:15 (fide GOYENECHEA & FLORES-VILLELA 2006
Gyalopion atavus LEVITON & BANTA 1961:2
Conopsis nasus — LINER 1994
Conopsis nasus — GOYENECHEA & FLORES-VILLELA 2006
Conopsis nasus — WALLACH et al. 2014: 181
Conopsis nasus labialis TANNER 1961
Conopsis nasus labialis TANNER 1961: 13
Conopsis nasus labialis TANNER 1985: 628
|Distribution||Mexico (Oaxaca, Chihuahua, Aguascalientes, Distrito Federal, Durango, Guanajuato, Hidalgo, Jalisco, Estado de Mexico, Michoacan, Morelos, Puebla, Queretaro, San Luis Potosi, Sinaloa, Tlaxcala, Veracruz and Zacatecas), elevation 1515 to 2950 m.|
labialis: Chihuahua (see comment)
Type locality: Milpas Durango (of neotype); see comment
|Types||Holotype: BMNH 188.8.131.52, possibly lost|
Holotype: BYU 16858, adult male. Collected at 6500 feet on July 18, 1960 by Wilmer W. Tanner and W. Gerald Robison. [labialis]
Holotype: CAS 89765 [atavus]
|Diagnosis||Chionactis differs from Conopsis in having a shovel-shaped snout with a deeply inserted lower jaw, genial shields separated by more than two scales, and 15 rows of scales at midbody. |
Gyalopion differs from Conopsis in having a pentagonal frontal scale, the rostral upturned, dividing the internasals and prefrontals and contacting the frontal, and nasal partially fused with first upper labial.
Diagnosis (of genus): The genus Conopsis is comprised of viviparous snake species with burrowing habits. These snakes are relatively small, adults of all species ranging from 100 to 330 mm in snout-vent length SVL; and from 120 to 377 mm in total length TL; body subcylindrical; head short; snout pointed; pupil round; 17 rows of smooth scales at midbody; anal and caudal scales divided; 12 to 14 conic maxillary teeth, with a distinctive groove at least on the last tooth; two internasal scales; a preocular; two postoculars; a rostral ended in a tip; nasal scale pierced by the nostril; frontal scale hexagonal; temporal formula 1+2; 2.5 to 3 upper labials before eye; hemipenes subcylindrical, with reticulate ornamentation, and several large spines at the base. Prefrontals and internasals may be fused or divided; loreals may or may not be present (20% of sample examined); genial shields divided by a scale in 90% of specimens, but may be fused or divided by two scales. Upper labials 7, in 90% of the specimens (they vary from 5 to 7); lower labials 6 in 80% of the specimens (varying from 4 to 7). Ventral scales 120–127; subcaudals 29–39. Coloration and body markings vary considerably, both dorsal and ventral patterns. Dorsal pattern consists of dark spots, blotches or bands on a variable ground color, that goes from light brown, cinnamon, grayish, and olive green tones. Dorsal spots may be constituted from a series of hexagonal to elongated marks, a tessellated pattern, or lines along the body. Some snakes have no dorsal pattern of spots. There is less variation ventrally, generally the belly is yellowish, although it may be reddish or grayish. Ventral spots may be present in a series of central dots, large or small, medial, intercalated or paired, some acuta with black edged ventre.
Diagnosis: This snake is characterized by the following combination of characters: fused prefrontals and internasals; upper labials 7, 6 lower labials (some populations with reduced number of these scales); light cinnamon dorsal coloration; with a vertebral line of hexagonal spots that may be bordered by two paravertebral rows of spots. Ventrally it is yellowish, with intercalated black dots. It differs from C. megalodon, the only species with which it could be mistaken, by the light cinnamon dorsal coloration, its larger body size (SVL: 100–320 mm in C. nasus and 107–250 mm in C. megalodon), and by its distributional range in the Mesa Central, which does not overlap with C. megalodon.
|Comment||Type species: Conophis nasus GÜNTHER 1858 is the type species of the genus Conopsis.|
The phylogenetic analysis (Goyenechea & Flores in prep.) suggests that Chionactis and Gyalopion may be the sister groups to Conopsis.
The type locality of Conopsis nasus is “California”.
|Etymology||The name Conopsis was derived from the Greek words cono, meaning "cone" and -opsis, meaning "having the appearance of," in reference to the conical shape of the snout.|
The specific name is derived from the Latin word nasus, meaning "nose."