Poachelas refugus, Haddad, 2010

Haddad, Charles R., 2010, A new species of Poachelas from Maputaland, South Africa (Araneae: Corinnidae), with considerable range extension for Poachelas striatus, African Invertebrates 51 (2), pp. 313-313 : 314-316

Poachelas refugus sp. n.

Figs 1–7

Etymology: The species name is Latin for fugitive, and refers to adults that evaded capture for several years during field trips at the type locality.

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 species group, defined by the presence of strong ventral leg spines in both sexes ( Haddad & Lyle 2008).

Description:

Female.

Measurements: CL 1.08–1.24, CW 0.87–0.99, AL 1.40–1.70, AW 0.83–1.00, TL 2.48– 2.80, FL 0.12–0.15, SL 0.68–0.73, SW 0.55–0.59, AME–AME 0.04, AME–ALE 0.01, ALE–ALE 0.20, PME–PME 0.07, PME–PLE 0.05, PLE–PLE 0.32. Length of leg segments: I 1.00+0.49+0.83+0.65+0.37= 3.34; II 0.84+0.44+0.65+0.56+0.32= 2.81; III 0.59+0.37+0.41+0.49+0.29 =2.15; IV 0.95+0.41+0.84+0.86+0.37= 3.43.

Carapace, including eye region, bright yellow, with pale grey stripe from PER to fovea, with short transverse extension near posterior end of marking ( Fig. 1 ); carapace flattened, slightly elevated from PER to fovea, with highest point at fovea, sloping gently to posterior; surface smooth, with scattered short fine setae; fovea indistinct, lying in shallow median depression, at ⅔ carapace length. Eyes surrounded by black rings; AER procurved, lateral eyes very slightly larger than medians ( Fig. 5 ); clypeus height equal to ⅔ AME diameter; AME separated by ½ their diameter; AME separated from ALE by approximately ⅛ AME diameter; PER recurved ( Fig. 1 ), median eyes slightly larger than laterals; PME separated by approximately ⅞ their diameter; PME separated from PLE by ⅔ PLE diameter. Chelicerae pale yellow­orange; anterior surface smooth, with scattered short fine setae; promargin and retromargin each with two small subequal teeth, each pair situated close together. Sternum creamy­yellow, yellow­brown along border; surface smooth, covered in fine setae ( Fig. 2 ); precoxal triangles present; intercoxal sclerites only present between endite and coxa I, and between coxa I and II ( Fig. 2 ). Abdomen creamy, with distinct dark grey dorsal median stripe running the length of abdomen ( Fig. 1 ); abdomen elongate, 1½ times longer than wide, broadest at ⅜ times its length; dorsal scutum absent; surface covered in short fine setae; two pairs of oval sigilla present, first pair indistinct, at ¼ abdomen length, second pair distinct, near ½ abdomen length ( Fig. 1 ); venter without sclerites. Legs I to IV yellow, anterior pairs slightly darker than posteriors; patellae, tibiae and metatarsi of leg I dark orange­brown, of leg II slightly tinged with grey mottling ( Fig. 3 ); all segments of anterior legs with several spines or spinules ( Figs 3, 4 ), posterior pairs without spines or spinules; leg cusps on anterior legs absent; metatarsi and tarsi with weak scopulae, remaining leg segments covered in short fine setae; all tibiae, metatarsi and tarsi with several dorsal trichobothria; metatarsi III and IV with terminal preening comb. Leg spination: femora: I pl 4 spines, pl 6 spinules; patellae: I plv 4, II plv 2; tibiae: I plv 12 rlv 12, II plv 9 rlv 9; metatarsi: I plv 8 rlv 8, II plv 8 rlv 8; tarsi: I plv 9 rlv 5 spinules, II plv 5–8 rlv 4 spinules. Epigyne with copulatory openings situated posteriorly in short semi­circular ridges ( Figs 6, 7 ); copulatory ducts directed anteriorly, looping before entering small oval anterior ST II, with transverse duct connecting ST II to lateral bilobed ST I.

Male. Unknown.

Holotype: ♀ SOUTH AFRICA: KwaZulu-Natal: Tembe Elephant Park, Pioneer grassland, 27°01.470'S: 32°24.346'E, base of grass tussocks, 5 xii.2009, C. Haddad (TMSA 23738).

Paratype: ♀ together with 4 immatures: same data as holotype (TMSA 23739) .

Distribution: Known only from the type locality ( Fig. 8 ).

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.

Figures

Figs 1–4. Digital microscope photographs of Poachelas refugus sp. n., holotype female: (1) dorsal habitus; (2) sternum, ventral, slightly lateral view, showing intercoxal sclerites (Is) and precoxal triangles (Pt); (3) anterior legs, prolateral view, indicating femoral (FeS), patellar (PaS), tibial (TiS), metatarsal (MtS), tarsal (TaS) spines and trichobothria (Tr); (4) femur (distal), patella and tibia (proximal) of leg I enlarged, prolateral view, showing spines (SP) and spinules (sp). Scale bars = 1.0 mm in Fig. 1, 0.5 mm in Figs 2–4.

Figs 5–7.Poachelas refugus sp.n. paratype female:(5) eye region, anterior view; (6) epigyne, ventral view; (7) vulva, dorsal view. Scale bars = 0.2 mm.

Fig.8.Distribution of Poachelas refugus sp.n.(diamond) and published (opencircles) and new (solid circles) records of P. striatus Haddad & Lyle, 2008 in South Africa. Shaded area indicates previously known distribution of P. striatus and broken line its new distribution.