Hapalopus aymara a new species of tarantula from Bolivia (Araneae, Theraphosidae, Theraphosinae)

A new species of Hapalopus Ausserer, 1875 (Araneae, Theraphosidae, Theraphosinae) from Bolivia is described and illustrated, based in males and females.

The Theraphosinae are the most speciouse subfamily of theraphosid spiders exclusively distributed in the Neotropical Region. They are characterized by the presence of an extended subtegulum, and keels in male palpal organ and the presence of urticating hairs of types I and/or III and/or IV (COOKE et al., 1972) on the dorsal surface of the abdomen (RAVEN, 1985;PÉREZ-MILES et al., 1996). More than 400 species were described in the subfamily but a high number of unknown species are expected to occur in Araneae as a whole (CODDINGTON & LEVI, 1991) and also in this taxa. Although the difficulties for systematic studies (SCHIAPELLI & GERSCHMAN, 1979;VALERIO, 1980;MINCH, 1989;RAVEN, 1990;BERTANI, 2000) due mainly to their morphological homogeneity, recent scientific contributions improve the tools for species recognition and consequently for the discovery of new species.
The genus Hapalopus Ausserer, 1875 includes eight species (PLATNICK, 2007) described from Brazil, Colombia, French Guiana, Mexico and Venezuela, the majority of which described in the second half of twenty century. FUKUSHIMA et al. (2005) transferred Cyriocosmus butantan Pérez-Miles, 1998 andMetriopelma nigriventris (Mello-Leitão, 1939) to Hapalopus and indicated the following synapomorphies to this genus: the ring-shaped keel on palpal organ, the presence of tibial apophysis with convergent branches and the presence of a spermathecal receptaculum having a membranous base. Hapalopus is also characterized by the following character combination: the apical region of the bulb subconical, bulbal keels inequal, digitiform apophysis of bulb absent, male palpal tibiae with retrolateral process, flexion of metatarsus I between tibial apophysis, femur IV without retrolateral scopula, absence of stridulatory setae and numerous labial cuspules (PÉREZ-MILES et al., 1996). Studying a sample collected in Beni, Bolivia, we found some individuals that present these characteristics but did not fit with any of the known species. In this study these specimens are described as Hapalopus aymara new species.
All measurements are expressed in millimetres. Coordinates into brackets are approximate (not taken by Global Positioning System). Numbers between parenthesis in the description, represent the mean and standard deviation of type series.
Etymology. Noun in apposition that refers to the name of the language and culture from an important region of Bolivia and Peru, the word means old language.
Diagnosis. Differs from Hapalopus formosus Ausserer, 1875, by the palpal bulb morphology by the absence of prolateral superior keel and 25% narrower ringshaped keel; from H. aldanus West, 2000, by the absence of basoventral cluster of short inward curled megaspines on metatarsus I, by the 40% narrower keel on palpal bulb, and femur III not swollen. Differs from H. tripepii Dresco, 1984 by the absence of a dorsal process in the cheliceral basal segment. From H. butantan (Pérez-Miles, 1998) by the 75% shorter embolus and the absence of abdominal stripped pattern. From H. nigriventris (Mello-Leitão, 1939), H. guianensis Caporiacco, 1954 andH. triseriatus Caporiacco, 1955 by the absence of abdominal spotted or stripped pattern. From H. nondescriptus Mello-Leitão, 1926 by the different palpal organ morphology in which embolus is twice longer in this species.
Distribution. Only know from the type locality.