Corinnomma semiglabrum ( Simon, 1896 ) Haddad, 2006
Haddad, Charles R., 2006, A new species of Corinnomma (Araneae: Corinnidae) from southern and eastern Africa, with taxonomic notes on C. olivaceum and C. semiglabrum, African Invertebrates 47, pp. 71-83 : 74-77
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|Corinnomma semiglabrum ( Simon, 1896 )|
Diagnosis: This species is recognised by the large, semi-circular depressions in which the copulatory openings are found, and by the U-shaped entrance ducts of the epigyne. The male can be recognised easily by the claw-like palpal embolus, which is distinctively coiled in other species.
Measurements: CL 2.9–3.5, CW 1.9–2.2, AL 3.6–3.8, AW 2.6–2.8, TL 7.1–7.9, FL 0.18–0.25, SL 1.43–1.65, SW 0.98–1.1. Interdistances between eyes:AME–AME 0.10, AME–ALE 0.07, ALE–ALE 0.44, PME–PME 0.20, PME–PLE 0.16, PLE–PLE 0.74.
Length of leg segments (sequence from femur to tarsus, and total): I 2.30+0.90+ 2.25+1.93+1.30=8.68; II 2.05+1.00+1.75 +1.65+1.20=7.65; III 1.95+0.90+1.35+1.75+ 0.85=6.80; IV 2.45+0.90+2.25+2.55+0.83=8.98.
Cephalothorax: Carapace dark brown to nearly black, finely wrinkled, clothed in very short white setae; elongate, broadest at midpoint ( Fig. 3 View Figs 3–9 ); highest at nearly one-third its length ( Fig. 4 View Figs 3–9 ). Fovea distinct, located slightly posterior to carapace midpoint; striae black, radiating outwards from fovea, fused to black markings laterally on carapace. AER procurved, eyes subequal in size; PER very slightly recurved, laterals very slightly larger than medians; all eyes surrounded by black rings; scattered long white setae on clypeus.Chelicerae dark brown, bulging very slightly beyond anterior margin of carapace ( Fig. 4 View Figs 3–9 ); long white setae on prolateral margin, scattered between short white setae; two teeth on promargin, proximal tooth bifid with single base; two simple teeth on retromargin. Sternum dark brown, nearly black, with faint black mottling; surface slightly granular; densely clothed with short white setae medially, and longer white setae near margins; single long black seta on sternum near each coxal base.
Legs: Femora I and II dark brown in proximal half, yellow distally; dark brown do stripe extending to end of femora; femur II with second pl stripe extending to three-quarters femur length; femora III and IV dark brown, with yellow marking pl at distal end. Patella I yellow with dark brown rlv stripe; patella II yellow with brown plv and rlv stripes; patellae III and IV dark brown. Tibiae I and II yellow do with brown median stripe, brown vt with yellow median stripe; tibiae III and IV dark brown. All metatarsi brown, with yellow distal tips.All tarsi yellow, brown in do proximal half; black markings on legs comprising plumose setae. Leg spination as follows: femora: I pl 1 do 3, II do 3, III pl 2 do 3 rl 1, IV pl 2 do 3 rl 1; patellae: all with 1 distal dtr; tibiae: I plv 3 rlv 2, II plv 2 rlv 2, III pl 2 rl 2 plv 2 rlv 2 vt 2, IV pl 2 rl 2 plv 2 rlv 1 vt 2; metatarsi: I plv 2 rlv 2, II plv 2 rlv 2, III pl 3 rl 2 plv 2 rlv 2 vt 3, IV pl 3 rl 3 plv 2 rlv 2 vt 2; all tibiae and metatarsi with numerous dtr, increasing in size distally. Palp dark brown; femur do 1; patella pl 1 do 1; tibiae pl 2 do 1; tarsus pl 2 (basal) pl 1 (median) vt 2. Single small terminal pectinate claw.
Abdomen: Oval, slightly globose, integument grey, broadest at two-thirds its length; leathery dorsal scutum present, dark red-brown, quite narrow, extending to two-thirds abdomen length; inframamillary sclerite absent; dorsum densely covered with short white setae; three black bands comprising plumose setae; first at front of abdomen, second at one-quarter abdomen length, third at half abdomen length; first and second bands fusing laterally at second band ( Fig. 4 View Figs 3–9 ).
Genitalic area and booklungs dark red-brown to nearly black, strongly sclerotised. Epigyne with copulatory openings situated laterally, anterior to lateral midline of epigyne, situated in semi-circular depression with strong antero-median ridges ( Fig. 5 View Figs 3–9 ); entrance ducts running in a U-shape, initially directed posteriorly, running medially and anteriorly; spermathecae round, with bean-shaped terminal receptaculae that touch or are slightly separated medially ( Figs 6, 7 View Figs 3–9 ).
Measurements: CL 2.65–3.60, CW 1.79–2.35, AL 2.60–3.35, AW 1.40–1.90, TL 5.50– 7.45, FL 0.23–0.26, SL 1.28–1.58, SW 0.90–1.05. Interdistances between eyes: AME– AME 0.12, AME–ALE 0.60, ALE–ALE 0.42, PME–PME 0.20, PME–PLE 0.15, PLE– PLE 0.73.
Length of leg segments (sequence from femur to tarsus, and total): I 2.00+ 0.70+2.15+1.85+1.54=8.24; II 1.80+0.75+1.65+1.55+1.05=6.8; III 1.85+0.80+ 1.50+1.75+0.80=6.7; IV 2.80+0.97+2.50+3.05+1.20=10.52.
General habitus similar to female described above; male less robust than female; abdomen more elongate and narrow, broadest at three-quarters its length; dorsal scutum covering entire dorsum; inframamillary sclerite present, rectangular, extending from epigastric furrow to in front of spinnerets.
Legs: markings on legs less distinct than for female. Leg spination as follows: femora: I pl 1 do 3, II do 3, III pl 2 do 3 rl 1, IV pl 2 do 3 rl 1; patellae: all with 1 distal dtr; tibiae: I plv 2 rlv 2, II plv 1 rlv 2, III pl 2 rl 2 plv 2 rlv 2 vt 2, IV pl 2 do 1 rl 2 plv 2 rlv 1 vt 2; metatarsi: I plv 2 rlv 2, II plv 1 rlv 2, III pl 3 rl 3 plv 2 rlv 2 vt 3, IV pl 3 rl 3 plv 2 rlv 2 vt 3; all tibiae and metatarsi with numerous dtr, increasing in size distally.
Male palp lacking retrolateral tibial apophysis; palpal tarsus compact; cymbium uniform red-brown; bulbus red-brown, somewhat square prolaterally; embolus claw-like, curving prolaterally, with a single, indistinct coil ( Figs 1 View Figs 1, 2 , 8, 9 View Figs 3–9 ); femur: pl 1 do 2; patella pl 1; tibia pl 2; tarsus do 1 pl 2, plv 1.
Holotype: ^deposited in MNHN (examined). Two labels accompany the types: ‘16961 Ap. semiglabrum E.S. / Makapan! // 16961’.
Other material examined: SOUTH AFRICA: Gauteng: 1^Crocodile River, Hartebeespoortdam, 13.xii.1991, collected from shrubs and trees, A. Leroy (NCA 92/444); 1^Florida, Johannesburg, xii.1918, R. Tucker (SAMC B6518). KwaZulu-Natal: 1ơ Greater St Lucia Wetlands Park, Hell’s Gate, Block B, 29.xi.2004, tsetse fly traps, J. Esterhuizen (NCA 2005/2026); 1^Lewombo mission, Zululand, 15.x.1977, under bricks, P. Reavell (NCA 2000/286); 2ơ 1^Ndumo Game Reserve, Pongola River floodplain, 26º53'S: 32º18'E, 12.ii.2005, leaf litter with Anoplolepis custodiens and Polyrachis gagates ants, C. Haddad (NCA 2005/48); 1^Tembe Elephant Park, Open woodland-sand, 27º03'S: 32º25'E, 14.i.2002, under log with Polyrhachis gagates ants, C. Haddad (NCA 2004/480); 1ơ same locality, 20.i.2002, under log with Polyrhachis gagates ants, C. Haddad (NCA 2004/479). Limpopo: 1^Gunfontein, 2428A2, 11.xii.1979, Falcon College & C.A. Car (NMZ 1377); 1ơ Klein Kariba, near Warmbaths, 27.xi.1996, running on ground, A. Leroy (NCA 2004/831); 1^Settlers, Tuinplaas, Springbokvlake (Lodge), 6.ii.2002, pitfall traps, grass, M. van Jaarsveld (NCA 2003/ 1331); 1^same locality, 6.ii.2002, pitfall traps, grass, M. van Jaarsveld (NCA 2003/1335); 3ơ Wolkberg Nature Reserve, near Haenertsberg, 21.xii.1994, leaf litter, J. Leeming (NCA 2004/832). SWAZILAND: 1ơ Lugaganeni, 29.xii.1998, A. Monadjem (NCA 2004/828). ZIMBABWE: 1ơ Bulawayo, Hillcrest, 2028B1, 12.ii.1991, L.H.B. Morris (NMZ 8746); 1^Bulawayo, Hillside, 20º10'S: 28º55'E, iii.1986, J.L. Minshull (NMZ 4341); 3^same locality, ii.1999, pitfall traps, M. FitzPatrick (NMZ 13838); 2^same locality, iii.1999, pitfall traps, M. FitzPatrick (NMZ 13863); 4ơ 3^same locality, ii.1999, pitfall traps, M. FitzPatrick (NMZ 13851); 1^Bulawayo, Natural History Museum, 2028B1, 13.xi.1985, I. Minshull (NMZ 5384); 1ơ Chiredzi, 2131B1, 16.xii.1979, S. Higgins (NMZ 809); 1^Nungu Farm, Girls College, 20º30'S: 28º29'E, 9–12.ii.1999, sweeping, NHMZ staff (NMZ 13712).
Distribution: Found in the northern and north-eastern parts of South Africa, Swaziland, and in the southern and south-eastern parts of Zimbabwe. Specimens have also been collected from Harare, Zimbabwe (M. Cumming, personal collection).
Biology: The bulk of the C. semiglabrum material examined was collected in pitfall traps or leaf litter, indicating that this is a primarily epigeic species. Observations of the species were conducted in the Tembe Elephant Park and Ndumo Game Reserve in South Africa, where it was found under logs, in leaf litter and in low foliage with the large silver-grey ant Polyrhachis gagates Smith, 1858 ( Hymenoptera : Formicidae ), which it mimics. At Ndumo, this species was also found near a colony of Anoplolepis custodiens (Smith, 1858) ants, with a few P. gagates ants in the near vicinity. The ant-mimicking Apochinomma formicaeforme was also found in association with this ant. Both species appear silver-grey in appearance, an effect which is achieved by silverywhite setae on the abdomens of these species. In C. semiglabrum , the mimicry effect is enhanced by three black transverse bands on the abdomen, which resemble the abdominal segments of their model. In A. formicaeforme , the carapace is much more elongate and the abdomen more globose, creating a better illusion than in C. semiglabrum . A single egg sac was produced by a captured female. It was round, constructed of tough, papery creamy-yellow silk (typical for Castianeirinae ), and was 8.8 mm in diameter. This sac contained 16 oval, cream eggs.
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