Austrachelas entabeni, Mbo, 2017

Mbo, Zingisile, 2017, A new species of the endemic South African spider genus Austrachelas (Araneae: Gallieniellidae) and first description of the male of A. bergi, Zootaxa 4323 (1), pp. 119-124 : 119-120

Austrachelas entabeni sp. nov. ( Figs 1–3 , 6, 7 )

Diagnosis. Females of A. entabeni sp. nov. are most closely related to A. bergi , sharing an elongate anterior epigynal hood (generally broader than long in other congeners). In A. entabeni sp. nov. the attachment of the anterior hood diverges anteriorly and the lateral hoods are small (arrows in Fig. 3 ), while in A. bergi the anterior hood is inserted at the posterior end of a membranous pentagonal anterior concavity, and the lateral hoods are elongate (arrows in Fig. 4 ). Male unknown.

Description. Female. Measurements: CL 3.53, CW 2.55, FL 0.30, SL 1.94, SW 1.45, AL 4.90, AW 2.80, TL 8.35, AME–AME 0.02, AME–ALE 0.01, ALE–ALE 0.22, PME–PME 0.05, PME–PLE 0.08, PLE–PLE 0.46.

Length of leg segments (sequence from femur to tarsus, and total): I 2.30 + 1.31 + 1.75 + 1.26 + 0.78 = 7.40; II 2.19 + 1.30 + 1.63 + 1.24 + 0.78 = 7.14; III 1.85 + 0.99 + 1.12 + 1.38 + 0.73 = 6.07; IV 2.50 + 1.29 + 1.79 + 2.15 + 0.85 = 8.58.

Carapace orange-brown with faint black mottling and radiating striae, slightly paler medially ( Fig. 1 ); AER strongly procurved, laterals larger than medians; AME separated by distance equal to 1/5 their diameter, AME separated from ALE by distance equal to 1/10 AME diameter; clypeus height equal to 4/3 AME diameter at AME, equal to 3/5 ALE diameter at ALE; PER straight, laterals larger than medians; PME separated by distance equal slightly less than 1/2 their diameter, PME separated from PLE by distance slightly more than 1/2 PME diameter. Chelicerae deep red-brown, with coarse transverse ridges; promargin with four teeth, proximal tooth smallest, second tooth largest, third and fourth teeth progressively smaller; retromargin with one small denticle, positioned between second and third promarginal teeth. Sternum and mouthparts bright orange-brown. Legs all orange in colour. Leg spination: femora: I pl 1 do 1, II pl 1 do 1, III pl 2 do 2, IV do 2; patellae: spineless; tibiae: I & II spineless, III pl 2 rl 2 plv 2 rlv 1 vt 2, IV pl 1 rl 2 plv 2 rlv 2 vt 2; metatarsi: I & II spineless, strongly scopulate, III & IV scopulate in distal half, III pl 5 rl 4 plv 1 rlv 1 vt 2, IV pl 5 rl 5 plv 2 rlv 1 vt 2; palp: femora do 2, patellae pl 1, tibiae pl 2 do 2 plv 1, tarsus pl 1 do 2 rl 1 plv 2 rlv 2. Abdomen dark grey dorsally, with creamy-grey chevron markings ( Fig. 1 ); paler grey laterally and ventrally, with dark grey mottled markings and V-shaped mediolateral marking ventrally ( Fig. 2 ); dorsum and venter lacking scutum or other sclerites, except two small pairs of dorsal sigilla and small post-epigastric sclerites. Female epigyne diverging posteriorly, with long narrow tongue-like anterior hood and small lateral hoods ( Figs 3 , 6 ); copulatory openings situated medially, just posterior to anterior hood, entrance ducts curving laterally, entering ST 2 on their ventral surface; ST 2 positioned anterolaterally, with broad loop and globose end, connected broadly to adjacent oval posterior ST 1 ( Fig. 7 ).

Type material. Holotype ♀: SOUTH AFRICA: Limpopo: Soutpansberg Mountains, ca. 20km N of Levubu, Entabeni Forest , 22°59'S, 30°17'E, 1360m a.s.l., leg. C. Griswold, 1–2.XII.1996 ( CAS, CASENT 9072373 ).

Distribution. Presently known only from the type locality in the Soutpansberg Mountains in the northern Limpopo Province ( Fig. 11 ). Together with the new distribution data for A. bergi presented below, A. entabeni sp. nov. extends the range of the genus approximately 300 km to the north of its previously known distribution ( Haddad et al. 2009). The updated distribution of the genus presented here suggests a possibility that Austrachelas may be recorded from Zimbabwe, Swaziland and Mozambique in the future.

Figures

FIGURE 11. Distribution of Austrachelas in South Africa, indicating type locality of A. entabeni sp. nov. (black star), type locality of A. bergi Haddad, Lyle, Bosselaers & Ramírez, 2009 (black circle), new localities of A. bergi (white circles), and distribution of other Austrachelas species (black triangles).

FIGURES 1 – 5. Digital microscope photographs of Austrachelas entabeni sp. nov. (1 – 3) and A. bergi Haddad, Lyle, Bosselaers & Ramírez, 2009 (4, 5): 1. Female holotype, dorsal habitus; 2. Same, ventral view of abdomen; 3, 4. Epigyne, ventral view; 5. Male palp, ventral view. Abbreviations: AH—anterior hood; EM—distal portion of embolus; ET—embolus tip; LH—lateral hoods; MAmedian apophysis. Scale bars: 1, 2 = 1 mm, 3 – 5 = 0.25 mm.

FIGURES 6 – 10. Genitalic morphology of Austrachelas entabeni sp. nov. (6, 7) and A. bergi Haddad, Lyle, Bosselaers & Ramírez, 2009 (8 – 10): 6. Female holotype, epigyne, ventral view; 7. Same, dorsal view; 8. Male palp, ventral view; 9. Same, retrolateral view; 10. Same, dorsal view. Abbreviations: CD—copulatory duct; dRTA—distal retrolateral tibial apophysis; DTA—dorsal tibial apophysis; EM – embolus; MA—median apophysis; pRTA—proximal retrolateral tibial apophysis; ST 1 — primary spermathecae; ST 2 — secondary spermathecae. Scale bars: 0.25 mm.