A new species of Tmesiphantes ( Araneae , Theraphosidae ) from the state of Pará , Brazil

A new species of Tmesiphantes Simon, 1892, T. aridai sp. nov., is described and illustrated based on three males and three females collected at the Floresta Nacional do Tapajós, Santarém, state of Pará, Brazil. Males can be distinguished from T. perp Guadanucci & Silva, 2012 by the palpal bulb with an inconspicous tegular basal projection, but presenting a very slender embolus with shorter keels not extending to the tip, and from T. nubilus Simon, 1892 by the tibial apophysis with two similarly sized branches, the prolateral one with a strong spine on the retrolateral margin. Females resemble T. nubilus by the aspect of the seminal receptacle but the constriction near the apex is less evident and apex shape is irregular. The new species represents the first record of Tmesiphantes from the Amazonian region, bringing the total number of species to eight.


ABSTRACT.
A new species of Tmesiphantes Simon, 1892, T. aridai sp.nov., is described and illustrated based on three males and three females collected at the Floresta Nacional do Tapajós, Santarém, state of Pará, Brazil.Males can be distinguished from T. perp Guadanucci & Silva, 2012 by the palpal bulb with an inconspicous tegular basal projection, but presenting a very slender embolus with shorter keels not extending to the tip, and from T. nubilus Simon, 1892 by the tibial apophysis with two similarly sized branches, the prolateral one with a strong spine on the retrolateral margin.Females resemble T. nubilus by the aspect of the seminal receptacle but the constriction near the apex is less evident and apex shape is irregular.The new species represents the first record of Tmesiphantes from the Amazonian region, bringing the total number of species to eight.
Tmesiphantes Simon, 1892 is a Neotropical genus of Theraphosinae, based on a couple of specimens of T. nubilus Simon, 1892 from the state of Bahia, Brazil, an Atlantic Forest domain.Males of Tmesiphantes can be recognized by the palpal bulb morphology, with conspicuous superior and inferior prolateral keels and long curved embolus, aspect of the tibial apophysis and by the metatarsus I, which bends to the retrolateral side of the retrolateral tibial apophysis, females can be distinguished by the spermathecae with two seminal receptacles, slightly constricted near the apex (Pérez-Miles et al., 1996;YaMaMoto et al., 2007), except in T. hypogeus (see Bertani et al., 2013, figs D, E).The genus was revised by YaMaMoto et al. (2007) with description of three new species: T. amadoi, known by a male, T. caymmii, known by male and female and T. bethaniae known by a male, all from the state of Bahia.Guadanucci & silva (2012) described the first two species registered outside the Atlantic Forest domain, from the state of Minas Gerais, Brazil: T. perp known by male and a female and T. riopretano based only on a male.Recently, Bertani et al. (2013) described T. hypogeus, based on two females collected in the Gruna da Parede Vermelha and Gruna das Cobras, also from Bahia.
During the identification of the mygalomorph spider's collection of the Faculdades Integradas do Tapajós, Santarém, Pará, Brazil, a new species of Tmesiphantes was identified.This new species, T. aridai sp.nov., comprises the first species recorded from the Brazilian Amazon rainforest, which is here described and illustrated.

MATERIAL AND METHODS
The material examined is deposited in the following institutions (abbreviation and curators in parentheses): Instituto Butantan, São Paulo (IBSP, A. D. Brescovit) and Faculdades Integradas do Tapajós, Santarém (FIT, H. M. Chalkidis).All measurements are in millimetres and were taken with a millimetric ocular lens.Total body length excludes chelicerae and spinnerets.Length of leg segments were measured between joints in dorsal view, length and width of carapace, eye tubercle, labium and sternum are maximum values obtained.Abbreviations: AME, anterior median eyes; ALE, anterior lateral eyes; PME, posterior median eyes; PLE, posterior lateral eyes; spines: ap, apical; d, dorsal; p, prolateral; r, retrolateral; v, ventral.Terminology: palpal bulb structures follows Bertani (2000), number and disposition of spines, Petrunkevitch (1925) and types of urticating hairs, cooke et al. (1972).Pictures were taken with a Leica DFC500 digital camera attached to a Leica MZ16A stereoscopic microscope.The spermathecae were dissected and cleared in lactic acid for internal structures observation and photographed in dorsal view.The left male palpal bulb was removed from the cymbium and photographed in dorsal, prolateral and retrolateral views.The left tibial spur was photographed in prolateral view, after having the setae removed for a  clearer view.The geographic coordinates were obtained using the program Google Earth and the distribution map was made using the program DIVA-GIS 7.5.Etymology.The specific name is in honour of Felipe Arida, grandson of the last author.

Tmesiphantes aridai
Diagnosis.Males of Tmesiphantes aridai sp.nov.resemble T. perp (see Guadanucci & silva, 2012, figs 11-13) and T. nubilus (see YaMaMoto et al., 2007, figs 3-5) by the morphology of the palpal bulb, but can be distinguished from T. perp by the palpal bulb with an inconspicuous tegular basal projection, but presenting a very slender embolus with shorter keels not extending to the tip (Figs 1-3), and from T. nubilus (see YaMaMoto et al., 2007, fig. 6) by the tibial apophysis with two similarly sized branches, the prolateral one with a strong spine on the retrolateral margin (Fig. 5).The females of the new species resemble T. nubilus due to the aspect of the seminal receptacles, but the constriction near the apex is less evident and apex shape is irregular (Fig. 6).