New Species

I’ve often wondered what it meant to find a new species. I questioned how they were officially found to be a new species and not just part of another species. I wondered what exactly was measured or tested and to what extent. I also wondered how the location in which they were found played into this decision as well. When I looked into what types of categories were considered, I found that in the case of a frog, adult morphology, osteology, larval external morphology, karyotype, chromosomal C-banded patters and Ag-NOR position as well as locations of where it is found all play a role in the distinction of a species. A specific example I found was the new species of Telmatobius (Anura: Leptodactylidae) found in northern Chile in 2005, described as the Telmatobius chusmisensis.

The experiments were done on nine adult frogs and 19 tadpoles which were all collected in Chusmisa. Specimens were collected by hand and by nets in the vegetation in flowing water as well as below stones. Multiple variables were measured with digital calipers including snout- vent length, head length, head width, thigh length, tibia length, foot length, eye diameter, interorbital distance, nostril-snout distance, and internarial distance. For tadpoles their total length, body length, tail length, maximum tail height, tail-muscle height, tail-muscle width, interorbital distance, and internarial distance were all measured. Chromosomal characteristics of one male and one female were measured as well. This was done by obtaining metaphase plates from the macertating intestinal epithelilium fragments. They were stained so that the C-band patterns and the Ag-NOR position could be seen.

Typically, anurans of the leptodactylid genus Telmatobius live in the higher aquatic environment of the Andes. Although there are about 50 species of Telimatobius, up till this finding, nine species were found in Chile. These are T.Peruvianus, T.marmoratus, T.zapahuirensis, T.pefauri, T.fronteriesis, T.halli, T.phillippii, T.dankoi, and T.villamensis. Most of these species inhabiting Chile are found in small bodies of water within desert habitat suggesting that it is probably indigenous to that area. Telmatobius chusmisensis, however, is restricted to a small stream located near Chusmisa.

T.chusmisensis, has a snout-vent length of 50.0 – 63.2 mm, a short snout that is depressed when viewing laterally, irregular apricot spots on both the dorsal and ventral sides of the thigh, webbed toes, a tongue that is almost completely attached to the bottom of the mouth, a large choanae, and all the tarsal elements are cartilaginous, to list a few. T.chusmisensis is different from other species within the genus Telmatobius, because of some of these features. For example all other species in Chile do not have all cartilaginous carpal and tarsal elements. They also do not have the irregular apricot spots on both the ventral and dorsal sides of the thighs as well. Geographically, T.chusmisensis is isolated from the northern and southern groups of Telmatobius.

T.chusmisensis is considered to be a member of Telmatobius due to it having specific characterisitics. T.chusmisensis has fang like teeth in the labial mucosa, Frontopatietals attached posteriorly, and nuptial excrescences on only the first finger. These are all thought to be a characterisitic of Telmatobius. The distribution of the species also suggests that the species is part of the Telmatobius genus. This then makes Telmatobius chusmisensis the tenth species of this genus found in Chile.

To me it’s remarkable that so many species have been found and that just within this particular genus Telmatobius, there have been over 50 species found. It makes me wonder how many species have yet to be discovered. It is also interesting to see how a species is categorized into a genus. As time goes on it will be interesting to see what other characterisitics other species will have.

HEH