28.08.2021

"Pterinochilus murinus" = Euathlus sp.

Recently we received an exuvia of a spider, which Nina Grimm had received as "Pterinochilus murinus" (Pic 1). But obviously it is a new-world tarantula. Now it was necessary to identify this spider Exuviae. Because of the habitus and the coloration we assumed a species of Euathlus or Phrixotrichus. But now this had to be verified taxonomically. Since our knowledge about the taxonomy of South American tarantulas is not that intensive, our dear colleague Steffen Esche, who is more familiar with this field, was consulted. Following the references of Perafán & Pérez-Miles, Steffen recommended clarification of various characters....

Thus, the following characteristics were found as confirming evidence, among others:

- Palptibia with spines only in the apical to medial region (Pic 2 + 3)

- spermathecae with broad base and lateral spheroidal chambers (Pic 4)

- Claw IV without 3rd claw and without dentition (Pic 5)

- No stridulation organ between palpcoxa retrolateral (Pic 6) and coxa I prolateral (Pic 7)

- Sternum longer than broad (Pic 8)

- Tarsi with 3 types of trichobothria [clavate (short), filiform (long), fusiform (medium-sized)] arranged dorsally in series (Pic 9)

Unfortunately, the urticating hair field could not be examined on the exuvia.

Resumé:

All clarified characteristics led to the realization that the animal of Nina is of course not a "Pterinochilus murinus", but a Euathlus sp.!

Reference:

Perafán, C. & F. Pérez-Miles (2014): The Andean tarantulas Euathlus Ausserer, 1875, Paraphysa Simon, 1892 and Phrixotrichus Simon, 1889 (Araneae: Theraphosidae): phylogenetic analysis, genera redefinition and new species descriptions. Journal of Natural History 48(39-40): 2389-2418