Thymopsis nilenta

Thymopsis nilenta is a species of decapods from the monotypic genus Thymopsis. It been 10 copies of these are native to the deep sea of the South Atlantic Hummerart were found.

Description

The rostrum is more slender, his back -side surface is flattened and has five to eight lateral peaks. Starting from the rostrum run two ridges spiked backwards. The sometimes very pronounced ridges or depressions on the carapace are provided with many small peaks or finely granulated. The individual segments ( somites ) of Pleons have a transverse recess. The telson is rectangular, its surface is granulated and has two rather indistinct ridges, which terminate in slanting rearward ( posterolateral ) mandrels.

The eyes are greatly reduced and not pigmented. The antennas have Stylocerite, surveys at the antenna base ( antennular peduncle ). The epistome is smooth, the second and third maxillipeds lacking Exopoditen.

The large claws on the first pair of walking legs are equal, laterally slightly compressed and have many small spikes on its surface. The length of the scissors finger is as long as the scissors hand. The cutting edges are provided with 20 to 25 small teeth. The tips of the scissors are rounded fingers inwardly and intersect during closing of the scissors. On the second and third pair of walking legs are very small scissors, the fourth and fifth is scherenlos. In contrast to the first pair of walking legs, the remaining pairs are smooth, have no spikes or thorns, but scattered tufts of hair.

In males, the first pair of swimming legs is short and stocky. Unlike those of the females, the separation of the two segments is no longer recognizable. On the second swimming leg pair the male is the "Appendix masculina ", a kind of clamp-like attachment, very short. Both in males and in females the endo-and Exopoditen the swim leg pairs are two to five relatively elongated. The uropods are relatively large and longer than the telson. The edge slightly hairy exopodite of uropod has a distinct diaeresis, a transverse recess.

Thymopsis nilenta reach body lengths of 15 cm, the carapace length excluding rostrum is 5 to 6 cm.

Distribution and habitat

Thymopsis nilenta is native to the South Atlantic near the Falkland Islands and South Georgia. The populated ocean depths are between 2000 and 3000 m. About the ecology and the habitat is not known. Among other things, due to the deep ocean depths without endangering species is suspected being perceived as " not at risk " ( "Least Concern" ) is classified.

Systematics and Taxonomy

In addition to this species or genus Lipke Holthuis described the genus Thymops Holthuis, 1974 and presented them with Thymopsis in its own subfamily, the Thymopinae Holthuis, 1974. Results of a phylogenetic analysis based No subdivision of the lobster family -like in sub-families, which is why they are no longer in use are.

The suffix '- opsis ' means literally ' appearance of', the genus name refers therefore to the morphological similarities with Thymops. From that distinguishes itself Tymopsis as. Well as from any other species of lobster -like, by the absence of Exopoditen to the second and third maxillipeds The holotype of the species Thymopsis nilenta was captured in 1966 during an expedition of the research vessel USNS Eltanin south of South Georgia (60 ° 06 'S, 36 ° 02'W -60 .1-36.033333333333 ). The epithet " nilenta " is not explained.