''Geophis nigroalbus'' is a species of

colubrid Colubridae (, commonly known as colubrids , from la, coluber, 'snake') is a family of snakes. With 249 genera, it is the largest snake family. The earliest species of the family date back to the Oligocene epoch. Colubrid snakes are found on ev ...

snake Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more j ...

in the subfamily

Dipsadinae Dipsadinae is a large subfamily of colubroid snakes, sometimes referred to as a family (Dipsadidae). They are found in most of the Americas, including the West Indies, and are most diverse in South America. There are more than 700 species. Dips ...

. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to the

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

of Colombia. It is sometimes known as the goo-eater snake.

Distribution

''Geophis nigroalbus'' is known a few localities in the Cordillera Occidental, and it has recently also been discovered in the

Magdalena Valley The Magdalena River Valley ( es, Valle del Río Magdalena) is a valley in Colombia located within the Colombian Andes. The valley is specifically situated between the Central and Eastern Ranges and crossed by the river of the same name, the Magda ...

, on the western slopes of Cordillera Oriental.

Description

''Geophis nigroalbus'' is a small species. An adult male specimen from the Magdalena Valley measures in snout–vent length and has tail. The upper surfaces of body and tail are uniform black. The venter is cream with black spots while the underside of the tail is black with a few cream patches. There are 134–149

ventral scales In snakes, the ventral scales or gastrosteges are the enlarged and transversely elongated scales that extend down the underside of the body from the neck to the anal scale. When counting them, the first is the anteriormost ventral scale that cont ...

in males and 141–157 in females, 42–51 subcaudal scales in males and 37–46 in females, and in total 180–197 segmentals in males and 181–203 in females.

Habitat and conservation

''Geophis nigroalbus'' is a fossorial species that occurs in tropical premontane wet forest at elevations of above sea level. The specimen from the Magdalena Valley was found actively foraging during the night in the leaf litter of a regenerative tropical rain forest after a strong rainfall of about one-hour duration. ''Geophis nigroalbus'' is a rare species and most collections consist of single specimens. Loss and degradation of the forest habitat is a threat to this species.

References

{{Taxonbar, from=Q3101261 Colubrids Snakes of South America Reptiles of Colombia Endemic fauna of Colombia Taxa named by George Albert Boulenger Reptiles described in 1908