The first Hapalotremus Simon, 1903 (Araneae: Theraphosidae) from Argentina: description and natural history of Hapalotremus martinorum sp. nov.

A new species of Hapalotremus Simon, 1903 from northern Argentina is described and illustrated. Hapalotremus martinorum sp. nov. differs from all other congeners by the colour pattern of live specimens. Males differ in the male palpal bulb morphology, with thickened and less curved embolus having a blunt subapical keel and less-developed apical keel. Females differ in the shape of the spermathecae, with the lateral bases more pronounced than the superiors and the upper edge more rounded. Specimens were captured inhabiting short burrows or crevices under stones in high cloud forests. Hapalotremus cyclothorax (Mello-Leitão 1923) is a junior synonym of Homoeomma montanum (Mello-Leitão, 1923), Hapalotremus scintillans (Mello-Leitão 1929) is a junior synonym of Pachistopelma rufonigrum Pocock, 1901, Hapalotremus exilis (Mello-Leitão 1923) and Hapalotremus muticus (Mello-Leitão 1923) are considered species inquirenda. http://zoobank.org/urn:lsid:zoobank.org:pub:1758F6FD-8883-445D-A757-0AC7E120DCF6


Introduction
Theraphosid tarantulas comprise 124 genera and 950 species (Platnick 2013), being the most speciose family of Mygalomorphae, which includes the largest spiders in the world. The subfamily Theraphosinae is endemic to the New World and has the highest species richness of the family Theraphosidae. Little is known about the natural biology of many species of Theraphosidae and its taxonomy has been considered to be in a chaotic state (Raven 1990). Despite the progress in the taxonomy of Theraphosidae in the last 20 years, much is yet to be done .
The genus Hapalotremus Simon, 1903 comprises six species distributed in Bolivia, Brazil and Peru (Platnick 2013). The type species, Hapalotremus albipes Simon, 1903 was described from a single adult male collected in Bolivia. This species is characterized by a whitish pattern on the dorsal abdomen and by white pubescence on the legs (from patella to tarsi), as Simon (1903) stated: "macula anteriore subtriquetra fulbvopilosa maculaque media majore subrotunda nigerrimo vellutina et albo-limbata decoratum, pedes albido-pubescentes". Gerschman de Pikelín and Schiapelli (1973) diagnosed the genus Hapalotremus and showed details of the tibial apophysis and the bulb Luis Pereira), Buenos Aires, Argentina. Spine notation follows Petrunkevitch (1925). Palpal bulb structure classification follows Bertani (2000). Classification of urticating setae follows Cooke et al. (1972). Images and illustrations of type material and additional material from Hapalotremus albipes were supplied to the authors by MNHN and SMF. Permission to use data, diagrams and images of examined material was obtained from colleagues (Fernando Pérez-Miles and Fabian Vol). All specimens were collected from areas outside Protected Areas and did not involve any endangered or protected species; hence collection and/or study permits were not required.

Diagnosis
Representatives of the genus can be distinguished from the remaining Theraphosinae by the presence of reddish or whitish setae (colour of live specimens) on dorsum abdomen, presence of Type III urticating hair, labium wider than long with reduced labial cuspules (from 5 to 7 in H. albipes and H. major), with the exception of Hapalotremus martinorum sp. nov. with 28 labial cuspules in females. It is characterized by the tarsi fully scopulated and divided by rows of setae increasing in width from legs I to IV, with tarsus IV divided by five or six rows of setae. Males of Hapalotremus are also recognized by the following features: tibial apophysis present with two branches, the prolateral bearing a long stiff black thorn on inner side, slightly curved at tip and of similar size to the spur, the retrolateral with a long spine inserted on inner side at the middle of the spur, metatarsus of leg I noticeably curved at base, and male palpal bulb with embolus subcylindrical curved to the retrolateral side with conspicuous subapical keel. Females may be also recognized by the single spermathceal receptaculum.  (MLP 19152). Paratype female (MLP 19153): same data as holotype.

Etymology
The specific epithet is a patronym in honour of Martin Hüsser (Switzerland) and Martin Gamache (Canada), who participated in the collection and discovery of this new species.

Diagnosis
Males and females of Hapalotremus martinorum sp. nov. differ from all other congeners by the colour pattern of live specimens with distinct greenish pubescence between the patella and tarsi of the legs, also on the lateral faces of the abdomen, and by the reddish setae of the urticating setae patch on the dorsal abdomen ( Figure 1). From H. albipes by the smaller size of adult males and females; males by the palpal bulb morphology with the thickened and less curved embolus having a blunt subapical keel and less-developed apical keel, and less curved metatarsus I ( Figure 2A, B, E). Females of H. martinorum differ from H. albipes Simon 1903 by the shape of the spermathecae, with the lateral expansions in the base being wider than apical portion; the upper edge is also more rounded ( Figure 3B, C). Hapalotremus martinorum sp. nov. resembles H. major (Chamberlin 1916) by the reddish setae on the abdomen dorsum but differs from this species by the smaller size and by the male palpal bulb morphology, with thickened and less curved embolus (Figure 2A, B).
Tibia I with ventral apophysis, the PB bearing a long stiff black thorn on inner side, slightly curved at tip and of similar size to the spur, RB with a long spine inserted on inner side at the middle of the spur ( Figure 2C). Metatarsus I moderately curved ( Figure 2E). Male palpal bulb with embolus subcylindrical, curved 70°to the retrolateral side. Prolateral keels present, the subapical keel (SA) conspicuous and blunt, the PS forming the embolus edge distally and pronounced; PI less-developed, apical keel not pronounced, R absent (Figure 2A, B).
Chelicerae with 12 large teeth on promargin and 13 small teeth on retromargin. Length of legs and palpal segments in Table 2. Tarsi I-IV fully scopulated divided by rows of setae increasing in width from legs I to IV. Metatarsi I one-half apical scopulated, II one-third apical scopulated, III one-quarter apical scopulated, IV one-quarter apical scopulated.

Distribution
Known only from the type locality (Figure 4).

Natural history
Hapalotremus martinorum sp. nov. was found inhabiting high cloud forest in the Yungas eco-region. This region comprises a hotspot of biodiversity in northern Argentina. The mean annual precipitation in this area is above 1000 mm; the mean temperature during April (autumn in southern hemisphere, when specimens were captured) is about 16.4°C and the relative humidity during this month is about 82.4% in the area. Individuals were found at 1496 m above sea level next to the Escoipe River and provincial Route 33 ( Figure 5A, B). The nearest locality to the point where spiders were found is Las Ánimas, at approximately 45 km from Salta city. Hapalotremus martinorum sp. nov. is a fossorial theraphosid that occupies short burrows or crevices under stones ( Figure 5C). Usually, the stones where individuals were found are covered with mosses and small ferns. This species could inhabit similar habitats as other theraphosids of the high cloud forests, as indicated by Pérez-Miles and Weinmann (2009)   consistent with that of H. montanum. The colour pattern with abdomen dark bearing numerous long reddish setae, the tibial apophysis with two branches bearing short apical spines, the bent metatarsus I and the shape of the bulb with a curved embolus are characteristics typical of Homoeomma species (Gerschman de Pikelín and Schiapelli 1972, Yamamoto unpubl. data). For these reasons, Hapalotremus cyclothorax is considered a junior synonym of Homoeomma montanum.

Notes
Hapalotremus scintillans was described from a single female from Caruaru (Pernambuco) (Figure 4) and the type material has been listed as "not located" in the annotated check list by Silva-Moreira et al. (2010) of Arachnida type specimens deposited in the Museu Nacional, Rio de Janeiro. Considering the type locality and the fact that the specimen was captured from inside bromeliads, H. scintillans could be a junior synonym of Iridopelma hirsutum Pocock, 1901or Pachistopelma rufonigrum Pocock, 1901(Bertani 2012. Both species had field records indicating a strict dependency on bromeliads occurring in the Brazilian Atlantic rainforest (Santos et al. 2004;Bertani 2012). Hapalotremus scintillans was originally described under Dolichothele, but later synonymized by Raven (1985). The general shape of the spermathecae presented by Bücherl et al. (1971) and Schmidt (2002) of other species originally described under Dolichothele, now Hapalotremus exilis, is also consistent with that of Pachistopelma rufonigrum (Bertani 2012). Moreover, the collector of the holotype of H. scintillans, D. Bento Pickel, is the same for the captured holotype of Avicularia pulchra Mello-Leitão, 1933, at Pernambuco state. Recently, Bertani (2012 considered A. pulchra a junior synonym of P. rufonigrum due to its geographical distribution and colour pattern. For these reasons and all the generic characteristics from the original description, Hapalotremus scintillans is a junior synonym of Pachistopelma rufonigrum.

Remarks
Hapalotremus exilis was described by a single female from Campina Grande (Paraíba) (Figure 4) and the type material has been listed as 'not located' in the annotated check list by Silva-Moreira et al. (2010) of Arachnida type specimens deposited in the Museu Nacional, Rio de Janeiro. According to the geographical distribution and many of the morphological characteristics from the original description, such as the small size of the female and the reduced number of labial and maxillary cuspules, together with the shape of the spermathecae presented by Bücherl et al. (1971) and Schmidt (2002) it could be a junior synonym of Oligoxystre (Guadanucci 2011) or Guruyita ) (Ischnocolinae). Unfortunately, the original description does not warrant recognition of the species, and, therefore the identity of H. exilis cannot be confirmed. The species is here considered species inquirenda, pending the finding of the type material or availability and careful examination of material from the type locality.

Remarks
Hapalotremus muticus was described by Mello-Leitão in 1923 from a single female collected in Villa Nova, state of Bahia, Brazil (Figure 4). Mello-Leitão noted a reduced number of labial cuspules (of about three or seven) and maxillary cuspules of about 10-12. The author also remarked that the tarsi of all legs are scopulated and undivided. The original description does not warrant recognition of the species, and, therefore the identity of H. muticus cannot be confirmed. The species is here considered species inquirenda, pending the finding of the type material or availability and careful examination of material from the type locality.

Discussion
Species of the Hapalotremus clearly show habitat preferences involving high altitudes at cloud forests and mountains of western South America. The species considered as valid in this work, H. albipes, H. major and H. martinorum sp. nov. are distributed in the biogeographic provinces Puna and Costal Peruvian desert ( Figure 6) at the South American Transition Zone of the Andean region (Morrone 2001(Morrone , 2006. This area extends along the highlands of the Andes between western Venezuela, northern Chile, and west central Argentina. Moreover, a close biotic links has been proposed between the Coastal Peruvian Desert and Puna (Fjeldsa 1992;Posadas et al. 1997;Morrone 2004). Hapalotremus martinorum sp. nov. was found living at the southern limit of the Puna biogeographic province ( Figure 6) at about 1500 m above sea level. This record is the lowest for the genus, considering that H. albipes and H. major live at altitudes between 2000 and 4000 m (Chamberlin 1916;Schmidt 2003;Krajick 2006). Krajick (2006) showed an image of a candidate H. albipes at the Cordillera Vilcanota in Peru at 4480 m and Chamberlin (1916) reported on a female H. major inhabiting altitudes of about 2895 m at Urubamba, Cuzco (Peru). The habitat of H. albipes at the Coastal Peruvian Desert involves an area of sparse vegetation, more abundant at both sides of rivers or next to the sea, and between 1500 and 3000 m the dominant vegetation comprises cacti and shrubs (Cabrera and Willink 1980;Morrone 2006). At the biogeographic province of Puna, H. albipes and H. major inhabit shrub steppes, montane grasslands with low shrubs, trees and grasses (Cabrera and Willink 1980;Figure 6. Distribution map of current Hapalotremus species in western South America at the Puna, Coastal Peruvian Desert and Yungas biogeographic provinces. Morrone 2006). Hapalotremus martinorum sp. nov. was captured next to the Yungas biogeographic province and occupying a different habitat type in relation to that of H. albipes or H. major. The Yungas is characterized by dry and cloud forests, especially rich on Lauraceae and Myrtaceae plants, alternating with Alnus accuminata and Podocarpus spp. forests. Morales et al. (1995) recognized three vegetation types: premontane subtropical forest, montane subtropical humid forest and temperate cloud forest, where H. martinorum sp. nov. was found. According to the species of Hapalotremus from eastern South America (all originally described by Mello-Leitão), their localities are placed in the Brazilian Atlantic Forest within the states of Paraíba, Pernambuco, Bahia and Rio de Janeiro (from north to south) (Figure 4). The Atlantic Forest is a region that extends along the Atlantic coast of Brazil from Rio Grande do Norte state in the north to Rio Grande do Sul state in the south. This region is characterized by the following phytophysiognomy: tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, Tropical and subtropical grasslands, savannas and shrublands, and mangrove forests (Dafonseca 1985). Some of these forests have between 700 and 1600 mm of precipitation annually with a distinct dry season. This includes deciduous and semi-deciduous seasonal forests each with their own lowland and montane regions. The Atlantic Forest is isolated from the Andean Forest mainly by the dry vegetation of the central depressions of the Chaco, resulting in an evolution of numerous endemic species (Dafonseca 1985). This large geographical barrier between the Hapalotremus species from the Andes and the Atlantic Forest, together with the advance during recent years in the study of the taxonomy of many theraphosid species from Brazil (Indicatti et al. 2008;Guadanucci 2011;Bertani 2012) led us to question the taxonomic status of the Brazilian Hapalotremus species. Moreover, the synonymies proposed by Raven (1985) involving Cyclothoracoides, Dolichothele and Goniodontium were made mainly considering only the reduced number of cuspules on the labium and maxillae, a widespread character between many theraphosid species (Guadanucci 2004(Guadanucci , 2007Indicatti et al. 2008;Guadanucci and Silva 2012;Guadanucci and Wendt 2014). Finally, a comprehensive cladistic analysis including all species of Hapalotremus is still needed to shed light on the status of the genus.