Revision of the Australian wolf spider genus Dingosa Roewer, 1955 (Araneae, Lycosidae)

The Australian wolf spider genus Dingosa Roewer, 1955 is revised to include four species: Dingosa simsoni (Simon, 1898) (type species); D. humphreysi (McKay, 1985), n. comb.; D. murata n. sp.; and D. serrata (L. Koch, 1877), n. comb. Dingosa belongs to the subfamily Lycosinae Sundevall, 1833 and differs from all other lycosine spiders by the structure of the male pedipalp, which has an enlarged embolic division and an unusually elongated tegular apophysis. The median septum of the female epigyne is inverted T‐shaped with the corners of the transverse part bent anteriorly in some species. Additional somatic characters, such as a raised cephalic region and distinct colour patterns of prosoma (narrow light longitudinal band between eyes) and opisthosoma (serrated cardiac mark) are unique within the Australian Lycosinae. Species within the genus Dingosa prefer sandy habitats with a sparse cover of vegetation where they construct a characteristic turret around their burrow entrance. All species mature in late summer to winter; females with eggsac can usually be found in July and August. The holotype of the Australian Dingosa topaziopsis (Hogg, 1896) is an immature spider and accurate species identification is not possible. This species is here considered nomen dubium. Dingosa is an Australian genus with much derived lycosine morphology. Other species from outside Australia currently included in this genus do not conform to the diagnosis of Dingosa. We propose the following new generic placements based on a critical evaluation of the original descriptions: Pardosa angolensis (Roewer, 1959), n. comb. (Angola), Pardosa completa (Roewer, 1959), n. comb. (Mozambique), Pardosa hartmanni (Roewer, 1959), n. comb. (Tanzania), and Trochosa ursina (Schenkel, 1936), n. comb. (China). We also support Mozaffarian and Marusik's (2001) previous suggested combination Trochosa persica (Roewer, 1955). Dingosa traghardi (Lawrence, 1947) (South Africa) was described from an immature female holotype which is lost; this species is here considered nomen dubium.


Introduction
The wolf spider genus Dingosa Roewer, 1955 was initially listed as nomen nudum (Roewer 1955a) and formerly described by the same author in a subsequent publication based on the female holotype of Lycosa simsoni Simon, 1898 collected in Launceston, Tasmania nomenclature follows Framenau (2006b) with the exception of female genitalia for which we applied the terminology of Sierwald (2000).
Photographs were taken with a digital camera (G6; Canon, Japan) that was connected to the optical tube of a stereomicroscope (MZ6; Leica Microsystems, Wetzlar, Germany) with an optical adapter set (MaxView 2 Plus; Scopetronix, Cape Coral, FL, USA). Photographs were taken in different focal planes (ca 10-15 images) and combined with the software package Helicon Focus 4.07 (Khmelik et al. 2006).

Diagnosis
Species of the genus Dingosa differ from all other species within the Lycosidae by a combination of somatic and genitalic characters. The cephalic area of the prosoma is  (Figure 2A), the light median band of the prosoma has two short and longitudinal dark lines between fovea and PLE, and there is a narrow median light band between the eyes ( Figure 1A-H). The opisthosoma has a unique serrated cardiac mark ( Figure 1A-H). Legs are comparatively longer than in many other Lycosinae, in particular in males (average ratio leg length to prosoma width: leg 154.7, leg 254.5, leg 354.4, leg 455.9; n54 species). In comparison, this leg ratio is much lower for the species of the Australian genus Venatrix (leg 153.6, leg 253.2, leg 353.0, leg 454.2; data for 17 species derived from  Framenau and Vink 2001). The embolic division is unusually large for members of the Lycosinae occupying at least half the length of the cymbium cavity, with long and curved terminal apophysis and embolus ( Figures 2C, 3A, 5A, 6A). The tegular apophysis is elongated and points more or less apically, in contrast to most Lycosinae in which it points retrolaterally.

Description
Medium-sized wolf spiders (TL 6.50-15.00). Males smaller than females. Prosoma longer than wide, dorsal profile with distinctly elevated cephalic region ( Figure 2A). Flanks of cephalic region steep in frontal view ( Figure 2B). Dorsal shield of prosoma brown to dark brown with light median and submarginal bands. Median band with two short dark lines between PLE and fovea, sometimes forming a V. Narrow white line of white setae medially between eyes. AME larger than ALE, AE row shorter than PME row; AE row slightly procurved ( Figure 2B). Chelicerae with three promarginal teeth, with the median largest and three retromarginal teeth of equal size. Labium about as long as wide, but generally little longer than wide in males and little wider than long in females. Opisthosoma dorsally light grey to dark olive-grey with distinct darker serrated cardiac mark in anterior half, accentuated by light lateral bands ( Figure 1A-H). Leg formula IV.I.II.III. Legs brown with longitudinal dark pattern (D. serrata, D. simsoni) or indistinct light patches (D. humphreysi, D. murata). Spination of legs: males: femur: three dorsal, two apicoprolateral, two retrolateral (D. humphreysi, D. serrata only), one apicoretrolateral (missing in D. murata); patella: one prolateral, one retrolateral; tibia: one dorsal in apical half, three ventral pairs, two prolateral, two retrolateral; metatarsus: three ventral pairs, two prolateral, one retrolateral, one apicoventral, one apicoprolateral, one apicoretrolateral. Females: three dorsal, two retrolateral (missing in D. humphreysi), two apicoprolateral, one apicoretrolateral; patella: one prolateral, one retrolateral; tibia: three ventral pairs, two prolateral; metatarsus: three ventral pairs, one apicoventral.
Male pedipalp with undivided, relatively narrow tegulum. Tegular apophysis elongated, pointing more or less apically, its tip straight or curved ventrally. Subtegulum narrow and situated basally on bulb. Embolic division large, terminal apophysis semicircular and broad at its tip, embolus originating prolaterally on embolic division and semicircular, long and relatively thin. Cymbium tip without macrosetae or spines.

Remarks
The genus Dingosa belongs to the subfamily Lycosinae as the male pedipalp has a transverse tegular apophysis (although somewhat elongated apically) with a sinuous channel on the dorsal surface (Dondale 1986;Murphy et al. 2006). The closest relative of this genus may be found in the monotypic Australian genus Mainosa Framenau, 2006(Framenau 2006a. Similar to Dingosa, Mainosa builds a turret around the entrance of their burrow and has very long legs, in particular in males. However, male and female genitalia show considerable differences and the coloration of spiders, with Mainosa having light transverse bars on an otherwise blackish opisthosoma, is very different.
The four species of Dingosa can be separated into two distinct groups based on somatic and genital morphology. Dingosa simsoni and D. serrata have very distinct serrated bands on the opisthosoma, whereas the tooth-like shapes on these bands are comparatively flat in D. humphreysi and D. murata. These two groups are also evident when comparing genital morphology. Males of both D. humphreysi and D. murata have a tooth basally on the tegular apophysis in the male pedipalp that is absent in the other two species, and the lateral edges of the transverse part of the median septum in the female epigyne curve anteriorly, but not so in D. simsoni and D. serrata.

Diagnosis
Dingosa simsoni is closely related to D. serrata, but differs in the curled tip of the tegular apophysis of the male pedipalp (keeled in D. serrata). The epigyne of D. simsoni is much shorter than that of D. serrata and has a distinct and continuous anterior margin whereas the anterior pockets are separated in D. serrata.

Description
Male. Based on WAM T62462.
Prosoma, dorsal shield ( Figures 1A, 2A): dark brown; indistinct black radial pattern; white radial lines of white setae; light brown median band widening from fovea towards PLE and here including two short and dark brown longitudinal lines that form an open V; narrow central line of white setae between eyes from behind PLE to clypeus and diagonal line of white setae between PME and PLE; distinct light brown submarginal bands; dark brown, blotchy marginal bands; white setae in median and submarginal bands; otherwise black setae; few brown macrosetae around eyes; six bristles below AE, one long bristle between AME.
Sternum: brown; white setae which are longer towards margins. Labium: longer than wide; dark brown; front end truncated and white. Chelicerae: light brown with few darker discolorations; basally covered with dense white setae. Pedipalps ( Figure 2C, D): terminal apophysis with broad tip, embolus strong with pointed tip; tip of tegular apophysis curled ventrally ( Figure 2E).
Opisthosoma ( Figure 1A): dark brown to black with laterally serrated median band; light yellow-brown lines laterally of serrated band; lateral sides of opisthosoma dark olive-brown; serrated band with silvery setae, serrated corners somewhat darker as they carry dark brown setae; white setae in yellow-brown bands. Venter light brown, somewhat darker centrally; covered with white setae, but a few brown setae laterally and in a patch centrally in front of epigastric furrow. Spinnerets brown.

Life history and habitat preferences
Dingosa simsoni is winter-mature. Adult spiders can be found between April, when the first males appear in search for females, and October. Females with eggsacs have been found as early as July, but appear to be most common in August and September.
Habitat descriptions for D. simsoni include ''sand dunes'' or ''base of sand dunes'', ''remnant bushland'', ''open shrubland of Acacia'' and ''mallee'' or ''mulga'' suggesting a preference for open, sparsely vegetated habitats on sandy or eroded dry soils. McCullough (2000) illustrated D. simsoni (as Pardosa serrata) and reported it common at his study site, near Burra, South Australia. Here, D. simsoni occupied stony, hard-packing clay-sandy loam soil on reefs of shale over sandstone bedrock. The vegetation consisted of patchy remnants of native and introduced grasses.

Remarks
Dingosa simsoni is currently associated with the common name ''Grey Wolf Spider''. However, this common name is based on the misidentification of this species by Hickman (1967) who re-described Lycosa simsoni as a large, trapdoor-building, burrowing wolf spider that is common in south-eastern Australia including Tasmania. It appears that Hickman (1967) did not examine the holotype female of D. simsoni but based his identification on a poor illustration of the epigyne in . Some popular spider books and webpages (e.g. Mascord 1970, p. 108;Australian Museum 2003) continued to identify the common trapdoor-building Grey Wolf Spider from south-eastern Australia as Dingosa, perpetuating Hickman's (1967) misidentification. The Grey Wolf Spider illustrated by Hickman (1967) is an undescribed species of an unnamed genus of Australian wolf spiders to which Lycosa leucophaeoides (L. Koch, 1877) also belongs. Walckenaer (1837) described the first wolf spider from Australia, Lycosa irrorata Walckenaer, 1837, based on a male collected in Tasmania. The species is currently catalogued as nomen dubium (Platnick 2007; based on Roewer 1955a). The type material could not be found in the MNHP, where Walckenaer's material was expected to be housed (E.-A. Leguin, personal communication). The original description suggests that this species could be a Dingosa, most likely D. simsoni as this species is the only representative of this genus in Tasmania. Walckenaer (1837, p 325) stressed in particular an elevated cephalic region (''Les quatre yeux des deux lignes postérieures sont portés sur un léger renflement du corselet''), which is very uncommon in Australian wolf spiders. However, the description is not detailed enough to undoubtedly support Lycosa irrorata as a senior synonym of D. simsoni.

Diagnosis
Somatic and genitalic characters place D. humphreysi close to D. murata. The longitudinal cardiac mark on the opisthosoma is less serrated than in D. simsoni and D. serrata in both species and males carry a small tooth at the base of the tegular apophysis of the male pedipalp. Males of D. humphreysi and D. murata can be distinguished by the shape of the tegular apophysis, which is curved apically in D. humphreysi but not so in D. murata. Females clearly differ in the shape of the epigyne. The median septum in D. humphreysi does not have truncated edges on the transverse part as evident in D. murata.

Description
Male. Based on WAM T48586.
Prosoma, dorsal shield ( Figure 1C): brown; indistinct dark brown radial pattern; light brown median band widening from fovea towards PLE and here including a V-shaped darker pattern; narrow median line of white setae between eyes; distinct light brown submarginal bands; indistinct narrow dark brown marginal bands; white setae in median and submarginal bands; otherwise brown setae; few brown macrosetae around eyes; four bristles below AE, one long bristle between AME.
Opisthosoma ( Figure 1C): light brownish grey through a dense cover of light setae; brown cardiac mark in anterior half accentuated by dark edges of dark setae. Venter yellow; covered with white setae, brown setae in a patch centrally in front of epigastric furrow. Spinnerets brown.
Epigyne, ventral view ( Figure 3C): median septum inverted T-shaped, its lateral ends reaching under the anterior pockets.

Etymology
The specific name is an adjective in apposition derived from muratus (Latin-surrounded by a wall) and refers to the turret-building behaviour of this species and all other species within the genus Dingosa.

Diagnosis
Dingosa murata is most similar to D. humphreysi. Males differ in the shape of the apical tip of the tegular apophysis, which is curved ventrally in D. humphreysi and more or less straight in D. murata. Females of both species are distinguished by the shape of the lateral tips of the inverted T-shaped median septum, which are truncated in D. murata, but reach under the anterior pockets of the epigyne in D. humphreysi.

Description
Male. Based on WAM T51303.
Prosoma, dorsal shield ( Figure 1E): dark brown; indistinct dark brown radial pattern; light brown median band widening anteriorly and with two irregular short bands in anterior half; dark brown around fovea; narrow central line of white setae between eyes from behind PLE to clypeus; distinct light brown submarginal bands; narrow dark brown marginal bands; black and interspersed white setae, white setae in median and submarginal bands; few brown macrosetae around eyes and behind PLE; four bristles below AE, one long bristle between AME. Sternum: shiny brown; white setae which are denser marginally. Labium: longer than wide; basally dark brown, otherwise brown; front end truncated. Chelicerae: dark brown, light brown longitudinal band frontally; few white setae basally, otherwise few black setae.
Pedipalps ( Figure 5A, B): terminal apophysis apically broad, with two tips, embolus thin, with bent tip; tegular apophysis with basal tooth and its tip more or less straight ( Figure 5B).
Opisthosoma ( Figure 1E): light brownish grey through a dense cover of silvery and white setae; dark brown cardiac mark with two minor lateral serrations, accentuated laterally by dark setae; yellow-brown bands lateral of cardiac mark; yellow-brown irregular spots in posterior half. Venter brown; covered with brown setae. Spinnerets light brown.

Diagnosis
Dingosa serrata is most similar to D. simsoni, but differs in the shape of the tegular apophysis of the male pedipalp which is keeled about halfway and has a broad tip (pointed tip curled ventrally in D. simsoni). The female epigyne is considerably longer than wide in contrast to all other species within Dingosa in which it is generally wider than long.

Description
Male. Based on WAM T62462.
Prosoma, dorsal shield ( Figure 1G): dark brown; indistinct black radial pattern; white radial lines of white setae; light brown median band widening anteriorly; two short and dark brown longitudinal lines behind PLE; narrow median line of white setae between eyes and diagonal line of white setae between PME and PLE; distinct light brown submarginal The majority of mature males were found in March and April, but some were recorded already in February and as late as June. Mature females were found from May to November, with highest numbers between May and August. Females with eggsac were recorded from July until November (see also Lane 1965;McKay 1979). Some females appear to persist through the summer months and copulate the following season (McKay 1979).
The burrow of this species is open, vertical and ca 10-20 cm deep. It is surrounded by a palisade made up of a variety of materials (McKay 1979). During summer, the turret is usually constructed of grass, but towards winter, there is a trend to use leaves and short pieces of wood for renovating and widening (Lane 1965). Burrows are usually restricted to areas where there is little or no slope (Lane 1965). Dingosa serrata uses the turret as a barricade whilst waiting for prey. The spider stands on the turret seemingly to increase the distance of vision (Lane 1965; V. W. Framenau, personal observation).

Remarks
Dingosa serrata was originally described from material of the Bradley Collection. The whereabouts of this collection is unknown and therefore the types are considered lost (Framenau 2005). However, L. Koch's (1877) accurate description and illustration of the epigyne leave no doubt about the identity of this species. Lane (1965) dedicated a large portion of his PhD studies to Dingosa serrata, however, examination of his reference material in the collection of the WAM revealed that his study was based on more than one species. His material also included, in smaller numbers, D. simsoni and D. murata. Similarly, records listed in McKay (1979) as Pardosa serrata include a considerable number of misidentifications and juvenile material that cannot be reliably identified to specific level. Consequently, the information provided by Lane (1965) and McKay (1979) as listed above must be treated cautiously in respect to species-level ecological traits.

Distribution
Western and South Australia, occasionally found in New South Wales, Victoria, and Queensland (Figure 7).

Species misattributed to Dingosa
In addition to D. simsoni, nine species from Australia, Africa, South America, China, and the Middle East were listed in Dingosa prior to this study (Platnick 2007). Critical evaluation of type material or the original species description reveals that none of these species can be attributed to Dingosa. To facilitate future revisions of these species we here propose more appropriate generic placements based mainly on the original descriptions.