A new species of Heser Tuneva, 2005 (Araneae, Gnaphosidae) from the south of India

Abstract A new species of Heser Tuneva, 2005 (Gnaphosidae) is described from the south of India. A key is provided to the species of Heser and the importance of Gnaphosidae for the study of world spider biodiversity is briefly discussed.


Introduction
Th e genus Heser Tuneva, 2005 belongs in the gnaphosid subfamily Zelotinae by the presence of metatarsal preening combs on legs III and IV, and was delimited by Tuneva (2005) based on the possession of a male palp with an elongated, hook-shaped median apophysis, and with a prolateral-basally inserted embolus which has a relatively narrow base and which is extending transversally across the distal end of the palpal bulb. Moreover, the genus can be distinguished from Zelotes Gistel, 1848 by lacking an intercalary sclerite and terminal apophysis of the male palp, as well as by the absence of coiled median and blind paramedian vulval ducts and the presence of glands on the insemination ducts in females, and it diff ers from most other zelotine genera by its large posterior median eyes. As a consequence, Heser resembles Camillina Berland, 1919 by the shape of the posterior median eyes, wich are large, subtriangular and almost contiguous. However, it diff ers from that genus by the absence of a bifi d, prolateral palpal terminal apophysis, by a diff erent shape of the embolar base and by the absence of a subtriangular to hemicircular anterior median epigynal plate. From Drasyllus Chamberlin, 1922, Heser also diff ers by the absence of a bifi d palpal terminal apophysis or a median epigynal plate, while it can be easily distinguished from Setaphis Simon, 1893 by the absence of a terminal coil on the embolus and from Zelowan Murphy & Russell-Smith, 2010 by its retrolateral tibial apophysis, which does not consist of two small triangular lobes. At present, Heser counts three species: the type species H. malefactor Tuneva, 2005, as well as H. aradensis (Levy, 1998) and H. infumatus (O. Pickard-Cambridge, 1872 which were transferred from Zelotes by Tuneva (2005). Th e genus has a known distribution area in the eastern Mediterranean, tropical Africa and central Asia (Murphy 2007). On an archaeological mission to the south of India in 2006 (Bosselaers and Valcke 2009), the author collected both sexes of a new species of Heser among the ruins of Hampi, the former capital of the Vijayanagar empire (Filliozat 2004, Fritz and Michell 2001, Verghese 2002. Th e new species expands the range of the genus to southern India (Fig. 20).

Material and methods
Th e specimens were observed, photographed and drawn under Euromex MIC 465 and Olympus SZC-X9 binocular microscopes equipped with an eyepiece grid and a Praktica DC42 digital camera.. Th e vulva (cleared in methyl salicylate) was observed and drawn using a Wild M12 compound microscope. All measurements are in mm, unless otherwise stated. Th e format for leg spination follows Platnick and Shadab (1975), amended for ventral spine pairs according to Bosselaers and Jocqué (2000). Leg spination is also illustrated in a schematic representation (Figs 9,11)  Diagnosis. Th e species can be distinguished from the other three species of Heser by the abdominal dorsal scutum in males, the pronounced S-shaped curve of the sperm duct, the small, transversally oriented median apophysis and the hook-shaped embolus tip circling the broad membranous conductor in the male palp, as well as the narrow anterior epigynal hood, the large spermathecae and the circular insemination ducts in females.
Etymology. Th e species epithet is a noun in apposition and refers to the imperial city of Vijayanagara (Hampi, Karnataka, India) among whose ruins the type specimens of the new species were found (Fig. 9).
Leg measurements: Male palp with a slender, basally-prolaterally inserted embolus circling more than half of the tegulum, having a hook-shaped tip pointing in prolateral direction, which is curling around the broad, membranous conductor. Median apophysis small and subtriangular, oriented transversally. Sperm duct with a pronounced, S-shaped curve in basal half of tegulum. Retrolateral tibial apophysis pointed, subtriangular (Figs 5-7, 13-14).

Discussion
Th e family Gnaphosidae is one of the largest spider families. In Platnick (2010), it is listed as the sixth largest family, with 114 genera and 2102 species. Moreover, since Araneidae and Th omisidae, which presently count more known species, have already been studied rather intensely, also in tropical regions, it is quite probable that Gnaphosidae will prove to be the fourth largest spider family known when it has been more thoroughly revised. Indeed, in spite of a number of excellent revisions being available (Platnick andShadab 1983, Platnick andMurphy 1984), a large number of species is still awaiting description, even in well studied regions such as Spain (Melic 2004, pers. comm.). Many newly discovered species turn out to be endemisms with relatively small distribution areas, again suggesting that many more remain to be discovered (Melic andBarriga 2007, Snazell andMurphy 1997).
Revisions from tropical or subtropical gnaphosid genera regularly result in a considerable number of new species, especially in the subfamily Zelotinae, the gnaphosids with metatarsal preening combs listed by Murphy (2007) as the "Zelotes-group" (Murphy and Russell-Smith 2010, Nzigidahera and Jocqué 2009, Platnick and Murphy 1996. Th e Gnaphosidae of the Indian subcontinent and its surroundings have been studied by Simon (1897), Reimoser (1934), Denis (1958) and Roewer (1961), and our knowledge about them has been compiled by Tikader (1982). Additional data were later published by Gajbe (1987Gajbe ( , 2005Gajbe ( , 2007 and Butt and Beg (2004). Heser has not yet been mentioned for the region, and none of the zelotine species illustrated by the aforementioned authors resembles the genus. It is possible that Heser species are rare, as three out of the four known species are only known from the type locality. Alternatively, Heser species may be frequently overlooked because of their small size and nocturnal habits (Levy 1998).
Th e recent progress made in the taxonomic study of ground spiders demonstrates that, for a long time to come, Gnaphosidae, and Gnaphosoidea in general, will remain a prime target for biodiversity studies within Araneae.