A New Species of Poachelas from Maputaland, South Africa (Araneae: Corinnidae), with Considerable Range Extension for Poachelas striatus

ABSTRACT A new species of the tracheline sac spider genus Poachelas Haddad & Lyle, 2008 (Araneae: Corinnidae), presently known only from southern Africa, is described. The genus has been represented by three species, all of which are suspected to be closely associated with grasses. The new species described here, P. refugus sp. n., is known only from females collected at the type locality, Tembe Elephant Park in Maputaland, South Africa. New collecting records of the type species of the genus, P. striatus Haddad & Lyle, 2008, described from three localities in the central Free State Province of South Africa and with a distribution range of about 100 km, are presented. The species is widespread throughout the province, and is also recorded from the Eastern Cape, Northern Cape and Mpumulanga provinces for the first time, expanding its range to approximately 900 km.


INTRODUCTION
The spider genus Poachelas Haddad & Lyle, 2008 (Araneae: Corinnidae) is one of seven tracheline genera recently described from the Afrotropical Region (Haddad 2006;Haddad & Lyle 2008;Lyle & Haddad 2009, 2010. It can be easily recognised from other trachelines by the elongate habitus and anterior legs, and pale colouration with a dark median abdominal stripe, adaptations to its apparent preferred microhabitat at the base of grass tussocks. Both sexes have strong paired ventral spines on the anterior tibiae and metatarsi, in addition to spines or erect setae on the anterior patellae. Known males of two species have ventral cusps on the tibiae, metatarsi and tarsi of leg I, and also on the metatarsi of leg II, which are absent in females (Haddad & Lyle 2008).
Poachelas are rarely collected by conventional methods (e.g. sweep-netting and pitfall trapping) and specimens can most easily be collected by searching at the bases of grass fauna of the Tembe Elephant Park in north-eastern KwaZulu-Natal Province, South Africa (Maputaland), immature specimens of an unusually spined clubionoid spider were collected in 2002,2004,2006 and 2007 by sweep-netting grasses and active searching in grass tussocks. Only following the description of Poachelas were additional immature new species of Poachelas, here described as P. refugus sp. n.
Fieldwork forming part of the South African National Survey of Arachnida (SANSA) has resulted in the collection of additional specimens of Poachelas striatus Haddad & Lyle, 2008 from quite widespread localities in South Africa. These new records are also presented here, greatly expanding the range of this species from about 100 km to 900 km. http://www.africaninvertebrates.org.za

MATERIAL AND METHODS
The specimens were studied under a stereomicroscope in 70 % ethanol for all measurements, photographs and drawings. The epigyne of the paratype female was dissected using entomological pins, cleared in a Labcon 5019U ultrasonic bath for 30 seconds, and drawn. Body measurements were taken of the larger holotype and smaller paratype females, and leg and eye measurements were taken for the holotype. All measurements were taken using an ocular micrometer on a Nikon SMZ stereomicroscope and are given in millimetres. Leg spination follows the format of Bosselaers and Jocqué (2000).
Digital photos of the holotype female were taken using a Nikon Coolpix 8400 mounted on a Nikon SMZ stereomicroscope. The extended focal range images were assembled using CombineZM image stacking software (http://www.hadleyweb.pwp.blueyonder. Figs 1-7 Etymology: The species name is Latin for fugitive, and refers to adults that evaded Diagnosis: This species is similar in size to P. montanus Haddad & Lyle, 2008 from South Africa but can be separated from P. montanus by the distinct abdominal stripe ( Fig. 1) and presence of strong spines on the anterior legs (Figs 3, 4), which are erect setae in P. montanus. Females of P. refugus sp. n. can be further recognised from others in the genus by the anteriorly directed looping copulatory ducts and small anterior ST II (Figs 6, 7). This species belongs to the Poachelas striatus the presence of strong ventral leg spines in both sexes (Haddad & Lyle 2008). Description:
Habitat and biology: Adults of this species are rare and initially only immatures were collected from the base of grass tussocks, and occasionally by sweeping, in pioneer grassland and sparse woodland habitats at the type locality. Adults were collected from grass tussocks in early summer (December). Despite exhaustive sampling in the nearby Ndumo Game Reserve, approximately 10 km west of Tembe, no specimens of this new species have been collected there (Haddad et al. 2006), suggesting an association with the pioneer grassland and sparse woodland habitats that form a mosaic with sand forest endemic to Maputaland (Matthews et al. 1999, 2001. These habitats and soils are absent from Ndumo and could possibly explain the absence of P. refugus from this reserve. It may very well occur in Maputaland to the north and south of Tembe, where suitable habitat is available.

Poachelas striatus Haddad & Lyle, 2008
Poachelas striatus See Haddad & Lyle (2008) for description of both sexes. Distribution: This species was described from three localities in the central Free State Province within a range of approximately 100 km (Haddad & Lyle 2008), all falling of the species' occurrence in the Savannah (Benfontein), Thicket (Paterson) and Nama Karoo Biomes (Colesburg and Tussen-die-Riviere Nature Reserve). Given this newly likely that P. striatus has a much broader distribution in South Africa and may occur wherever suitable grasses and grass densities are found. Only once additional focused sampling for this species has been done, can the environmental parameters restricting its distribution be determined. The new records reported here extend the range to the eastern, southern and western parts of the Free State, eastern Northern Cape, southern Eastern Cape and Mpumulanga provinces, thereby expanding the range of the species to approximately 900 km (Fig. 8).
case of sympatry in the genus. At this locality P. striatus and P. montanus appear to be altitudinally separated. P. striatus occurs in the grassland plains at the base of Platberg (altitude ca 1750 m), consistent with its habitat at other localities. This represents the highest altitude at which P. striatus has been collected thus far. In contrast, P. montanus occurs on the top of Platberg in montane grassland at an altitude of about 2300 m.
Habitat and biology: The species is typically found at the base of grass tussocks of various genera (Themeda, Eragrostis, Cymbopogon, Panicum etc.) in open grassland sented from an agroecosystem (maize at Delmas). Further details on the biology are provided in Haddad and Lyle (2008). CONCLUSION The description of P. refugus increases the known diversity of the genus to four species. This genus is relatively stable regarding somatic morphology, particularly the elongate body shape and strong leg spines ventrally on the anterior legs. However, the genitalic structure of the three known females is quite variable, and provides another example of stable somatic morphological templates accompanied by a complex range of genitalic structures. With further focused sampling at the base of grass tussocks in Africa it is likely that several more Poachelas species will be discovered. Only once a broader diversity of species is known can the extent of genitalic variation in the genus be truly appreciated.

ACKNOWLEDGMENTS
Leon Lotz and Ansie Dippenaar-Schoeman are thanked for making available some recently collected specimens for study. This work was funded by the National Research Foundation (NRF) of South Africa through a grant to the author in the Thuthuka or recommendations expressed in this material are those of the author and therefore the NRF does not accept any liability in regard thereto. Charles Griswold (Californian Academy of Sciences, USA) and an anonymous referee are thanked for their comments that helped to improve the manuscript.