Description of six new species of Trachelas Koch, 1872 (Arachnida: Araneae: Corinnidae) in Brazil

GONZÁLEZ MÁRQUEZ, M. EUGENIA

Porto Alegre

Congreso; XXX Congresso Brasileiro de Zoologia; 2014

Grupo de Ecología de Insectos (INTA Bariloche), Universidad Nacional del Comhaue, CONICET, IMBECU y la Sociedad Argentina de Entomología

The genus Trachelas Koch includes 81 species distributed worldwide. Its species have a bright red carapace which contrasts with a pale white or orange abdomen. However, the rest of the morphological features such as the genitalia, the shape of the endites, the cheliceral dentition, and the distribution of trichobothria is highly variable. The American Trachelas form a distinct group which can be divided into four species groups: tranquillus, speciosus, bispinosus and bicolor. In the bispinosus and bicolor groups the male embolus is not a separate sclerite but a distal continuation of the tegulum and the females generally lack the anteriorly folded lateral ducts typical of the tranquillus and speciosus groups. They have a distribution that ranges from northern Mexico to southern Brazil. The bispinosus group may be recognized by the unusual lateral spurs on the endites of males. These species have three or four retromarginal cheliceral teeth, and the median ducts of the female have characteristic basal enlargements. The present study describes six new species of the bispinosus group. It will present illustrations of sexual morphological characters for diagnosis as well as images and distribution maps. Trachelas sp. 1 can be distinguished by the relatively small epigynal depression, epigynal openings situated close to anterior margin, longs lateral ducts extending beyond epigynal openings and median ducts with simple coil. Male palp with short, blunt terminal apophysis, straight and thin conductor almost reaching tip of embolus and long retrolateral tibial apophysis. Trachelas sp. 2 can be distinguished by the presence of long embolus, a long conductor almost reaching tip of embolus and the absence of the terminal apophysis. Trachelas sp. 3 can be distinguished by the epigynal openings situated anteriorly, long lateral ducts and median ducts with many irregular coils. Trachelas sp. 4 can be distinguished by the presence of long embolus, a long conductor twice the length of the embolus and the absence of the terminal apophysis. Elongated RTA abruptly thinned in distal half. Trachelas sp. 5 can be distinguished by the large epigynal depression, epigynal openings relatively small, situated medially, and longs lateral ducts. Trachelas sp. 6 can be distinguished by the strong curved spine shape of embolus, a short and thin conductor and the absence of terminal apophysis.