Three new species of Melloleitaoina Gerschman & Schiapelli, 1960 (Araneae, Mygalomorphae, Theraphosidae) from northern Argentina

Abstract Three new species of the monotypic genus Melloleitaoina Gerschman & Schiapelli, 1960 are described from northern Argentina: M. mutquina sp. n., M. uru sp. n. and M. yupanqui sp. n. The female specimen originally described as M. crassifemur is not conspecific with the male holotype and thus is removed from this species and described as M. uru sp. n.; M. crassifemur is redescribed. All species are diagnosed, illustrated and a key to species is provided.


Introduction
The subfamily Theraphosinae (Theraphosidae) is a speciose group of tarantulas distributed exclusively in the New World, whose greatest diversity is found in South America. Most tarantulas have cryptic habits, are predominantly nocturnal sit-and-wait hunters and have long lifespans. Females can live between 15 and 30 years while males live for significantly shorter periods of time (Locht et al. 1999, Costa andPérez-Miles 2002). Juveniles and adult females are sedentary while mature males disperse in search of females. Consequently several species have only been described on the basis of a single sex and the subsequent assignment of a specimen as a conspecific of the opposite sex is problematic.
The monotypic genus Melloleitaoina was established by Gerschman and Schiapelli (1960) on the basis of a single male specimen of the type species Melloleitaoina crassifemur, from Salta, Argentina. Later in 1973 the same authors illustrated the female spermathecae of a specimen from a location near the type locality in the same province. Raven (1985) considered Melloleitaoina a junior synonym of Dryptopelma Simon, 1889, but was restored by Pérez-Miles et al. (1996). This genus is morphologically similar and phylogenetically related to Tmesiphantes, Plesiopelma and Homoeomma (Pérez-Miles et al. 1996, Yamamoto et al. 2007.
Melloleitaoina is characterized by having a reduced number of labial cuspules, legs with few spines, all tarsal scopulae divided and lacking scopulae on metatarsal IV. Males have a thickened femur III, palpal organ with a long and curved embolus, and tibial apophysis with two very unequal branches. Females have spermathecae with two granulated seminal receptacles with a slight constriction near the apex (Gerschman and Schiapelli 1960, Gerschman and Schiapelli 1973, Pérez-Miles et al. 1996, Yamamoto et al. 2007.
Our study of the types and additional material deposited in the Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", led us to determine that the female of M. crassifemur is not conspecific with male holotype when contrasted with males from the same locality of the female. Also we found other individuals that fit with the diagnosis of the genus but are undescribed; they are described as new species herein.

Material and methods
Urticating setae terminology follows Cooke et al. (1972) and Bertani (2002). Male palpal organ keel terminology follows Bertani (2000). All measurements were taken using an ocular micrometer and are given in millimeters (mm). We measured left legs and palps unless they were lost; measurements were taken in dorsal view along the central axis of the segments. Photographs were taken with a Lumenera Infinity Lite camera adapted to a stereoscopic microscope Olympus SZ 61. The geographic coordinates were determined using the Global Gazetter (www.fallingrain.com). The distribution map was produced using DIVA-GIS 7.5 (www.diva-gis.org). The material examined is deposited in the Museo Argentino de Ciencias Naturales "Bernardino Rivadavia" (MACN).
Affinities. Melloleitaoina species share with Plesiopelma Pocock, 1901 and Tmesiphantes Simon, 1892, principally by the general morphology of the palpal bulb and tibial apophysis. Melloleitaoina males can be distinguished additionally from those of Plesiopelma by lacking nodule on metatarsi I and having only III-IV intermediated urticating setae. They can be distinguished from Tmesiphantes by having sigillas more rounded, male femur III incrassate and female spermathecae with granulated seminal receptacles and spiniform setae on promargin of coxae III and IV.
Distribution. Northern Argentina. Catamarca, Salta and Jujuy provinces (Fig. 1). Diagnosis. Male differs from other Melloleitaoina species by the palpal bulb morphology with very curved embolus without triangular tooth, well-developed and subequal PI and PS (Figs 3 and 4), and apex widened (Fig. 5). Females unknown.

Melloleitaoina mutquina
Etymology. The specific epithet mutquina is a noun taken in apposition and means place or thing to smell in Quichua language and refers to the locality of Mutquín, where this species is distributed. It denotes the aroma of the flora of the region that emerges especially after rains, perfuming the village of aromatics herbs. Diagnosis. Males differ from other Melloleitoina species by the palpal bulb morphology with very curved embolus with a conspicuous subapical triangular tooth and well-developed PI and PS (Figs 16-18). Females differ from other Melloleitaoina species by the shape of the spermathecae with elongated seminal receptacles with small granules (Fig. 15).
Diagnosis. Male differs from other Melloleitaoina species by the palpal bulb morphology with a discontinuous PS, formed by two separate keels, very curved embolus without triangular tooth, well-developed PI and PS, and apex widened (Figs 26 and 28). Female differs from other Melloleitaoina species by the shape of the spermathecae with short seminal receptacles with large granules (Fig. 25).
Etymology. The specific epithet is a patronym in honor to the most important Argentine musician of folklore Atahualpa Yupanqui, pseudonym of Héctor Roberto Chavero Aramburu (Juan A. de la Peña, Argentina, 1908-Nimes, Francia, 1992.

Key to males of Melloleitaoina species
1 Palpal bulb with a triangular tooth on the embolus (Figs 16-18