15.03.2022

An unknown Ornithoctoninae from an Import is an undescribed Ornithoctonus sp.!

in one of the last articles on our THERAPHOSID RESEARCH TEAM Webpage we had reported about the first results of an identification of an import of tarantulas from Asia (= see here).

Thorsten Trapp kindly asked us to identify the animals he imported.

Here now follows the report about the identity of another new species from this import.

The 2 spiders examined here obviously originate from Thailand, from Tak province (Pic 1). They show all the necessary characteristics of females of the genus Ornithoctonus (We follow the Data from von Wirth and Striffler 2005 and new unpublished results):

• Single-lobed undivided spermathecae, dented to half their height or deeper (Pic 2).

• only a maximum of 6 spines on met. IV

• spines above suture of palpcoxa pl (except O. costalis).

• Stridulatory organ on palpcoxa pl consists of a "frontspine" followed by a horizontal or slightly upward double row of elongate Stridulatory spines which have a narrow base (Pic 3).

• Sternum elongate (Pic 4).

Within the genus Ornithoctonus the following described species are also distributed in Thailand/Myanmar:

Ornithoctonus andersoni, Ornithoctonus costalis and Ornithoctonus aureotibialis (The present specimens were compared with the holotype specimens of the mentioned species).

The present specimen differs from Ornithoctonus andersoni by the absence of spines above the suture on the tastercoxa and by the spermathecae not being quite so deeply dented. Also by the narrower fovea, by the greater number of stridulation bristles on the chelicerae retrolaterally (Pic 5), and by the smaller number of spines on Met. IV (andersoni = 5, present specimen = 4).

The the studied spider differs from Ornithoctonus aureotibialis by the absence of spines above the suture on the coxa of Palp and by the absence of the orange pubescence on the outer sides of the tibia and patella of the frontlegs, and by the smaller number of spines on Met. IV (aureotibialis = 5, present specimen = 4).

The specimen differs from Ornithoctonus costalis by the distinct deeper dent in the middle of the spermathecae as well as by the different coloration e.g. from the carapace, which is beige in O. costalis.

Resumé:

In our opinion these specimens from Tak Province in Thailand, which were available for examination and identification, are a so far undescribed Ornithoctonus species which is close to Ornithoctonus costalis, because also the localities of both are not far apart.

Reference:

Wirth, V. von & Striffler, B. F. (2005). Neue Erkenntnisse zur Vogelspinnen -- Unterfamilie Ornithoctoninae, mit Beschreibung von Ornithoctonus aureotibialis sp. n. und Haplopelma longipes sp. n. (Araneae, Theraphosidae). Arthropoda 13(2): 2-27.