Nyikoa limbe, Huber, Bernhard A., 2007

Huber, Bernhard A., 2007, Two new genera of small, six-eyed pholcid spiders from West Africa, and first record of Spermophorides for mainland Africa (Araneae: Pholcidae), Zootaxa 1635, pp. 23-43 : 26-30

Nyikoa limbe , n. sp.

( Figs. 2–3 , 13–31 )

Type material. Male holotype from Cameroon, Southwest Province, Fako Division, Limbe Subdivision, 1.4 km NE of Etome (04°03.0’N, 09°07.6’E), ~ 400 m a.s.l., January 13–19, 1992 (S. Larcher, G. Hormiga, J. Coddington, C. Griswold, C. Wanzie), in USNM.

Etymology. The species name is derived from the type locality, and is used as a noun in apposition.

Diagnosis. Small but long-legged six-eyed pholcine (proximo-lateral cheliceral apophyses!), easily distinguished from other known pholcines by unique and extremely complex procursus ( Fig. 14 ). Further distinguished from other African six-eyed pholcines by combination of following characters: male cheliceral apophyses without modified hairs ( Fig. 15 ); epigynum without scape ( Fig. 16 ); prolateral attachment of bulb ( Fig. 13 ); absence of retrolateral notch proximally on cymbium ( Fig. 14 ); widely spaced eye triads ( Fig. 2 ); presence of several ALS spigots (versus two) ( Fig. 26 ); shift of tibia-cymbium joints to prolateral (rather than to retrolateral) side ( Fig. 13 ).

Male (holotype). Total length 1.7, carapace width 0.60. Leg 1: 14.0 (3.4 + 0.3 + 3.6 + 5.4 + 1.3), tibia 2: 2.2, tibia 3: 1.3, tibia 4: 2.4. Tibia 1 length/diameter (L/d): 50. Habitus as in Figs. 2, 3 ; coloration mostly pale ochre-yellow, abdomen pale ochre-gray; distance PME–PME 175 µm; diameter PME 70 µm; distance PME– ALE 15 µm; AME missing. Sternum wider than long (0.44/0.38), unmodified. Clypeus unmodified; chelicerae with pair of simple frontal apophyses ( Figs. 15 , 24 ), without stridulatory ridges. Palps as in Figs. 13, 14 ; coxa unmodified, trochanter simple, without apophysis, femur, patella and tibia widened but otherwise unmodified; procursus distinctive, highly complex ( Figs. 18–21 ), bulb with bifid projection, one part membranous (embolus?), other part thin blade-like; palpal tarsal organ capsulate ( Fig. 22 ). Legs without spines and curved hairs, few vertical hairs; retrolateral trichobothrium of tibia 1 at 12%, prolateral trichobothrium apparently absent on tibia 1, present on other legs; tarsus 1 with>10 pseudosegments, but only distally a few visible in dissecting microscope; tarsus 4 with complex comb-hairs ventrally ( Fig. 23 ). Male gonopore without epiandrous spigots ( Fig. 25 ). ALS with one widened, one pointed, and five cylindrically shaped spigots ( Fig. 27 ).

Variation. Tibia 1 in other males: Cameroon (type locality, N=9): 3.4–3.8 (mean: 3.54), Ghana (N=20): 3.0–3.7 (mean: 3.33), Congo DR (N=20): 3.2–3.7 (mean: 3.45). No variation seen in genitalia and chelicerae.

Female. In general similar to male. Tibia 1: Cameroon (N=6): 3.2–3.4 (mean: 3.27), Ghana (N=22): 2.9– 3.3 (mean: 3.08), Congo DR (N=20): 3.0–3.4 (mean: 3.21). Epigynum very inconspicuous from outside, barely distinguishable from surrounding cuticle but somewhat protruding, with pair of pockets close together ( Fig. 29 ); with round pore plates and complex ‘valve’ separating uterus externus from uterus internus ( Figs. 17 , 31 ).

Distribution. Apparently widely distributed, currently known from three localities in Ghana, Cameroon, and Congo DR ( Fig. 74 ).

Material examined. CAMEROON: Southwest Province, Fako Division, Limbe Subdivision, 1.4 km NE of Etome: type above, together with 7ɗ4Ψ, in USNM. Same data, 3ɗ2Ψ in CAS. GHANA: Kakum forest (5°20’N, 1°23’W), fogging in secondary forest, Nov. 19, 2005 (R. Jocqué, D. De Bakker, L. Baert), ~25ɗ29Ψ in MRAC (217.690); same data but various dates (Nov. 15–24, 2005), ~8ɗ8Ψ in MRAC (217.689, 217.721, 217.730, 217.734, 217.738); same data but primary forest, various dates (Nov. 14–25, 2005), ~22ɗ37Ψ in MRAC (217.693, 217.702, 217.709, 217.718, 217.736). CONGO DR: Bas-Congo, Mayombe, Luki Forest Reserve, fogging in primary rainforest, Nov. 4–13, 2006 (D. De Bakker, J. P. Michiels), ~27ɗ54Ψ in MRAC (4 vials, separated from 219.850–1, 219.853–5); same locality, beating along trail in primary rainforest, Nov. 5, 2006 (D. De Bakker, J. P. Michiels), 1ɗ1Ψ in MRAC (219.973).

Figures

FIGURE 74. Map showing the known distributions of Nyikoa n. gen. and Anansus n. gen., as well as the only known record of Spermophorides in Africa.

FIGURES 2 – 12. Photographs of habitus and female abdomens. 2, 3. Nyikoa limbe, male in dorsal and lateral views. 4, 5. Anansus aowin, male in dorsal and lateral views. 6 – 8. Anansus ewe, male in dorsal, lateral, and ventral views. 9. Anansus ewe, female abdomen, ventral view. 10. Spermophorides africana, female abdomen, ventral view. 11, 12. Spermophorides africana, male in dorsal and lateral views.

FIGURES 13 – 17. Nyikoa limbe n. sp. 13, 14. Left palp, prolateral and retrolateral views. 15. Male chelicerae, frontal view. 16, 17. Cleared epigynum, ventral and dorsal views. b, bulb; e, putative embolus; p, procursus. Scale lines: 0.2 mm.

FIGURES 18 – 25. Nyikoa limbe n. sp. 18 – 21. Left procursus, retrolateral (18), ventral (19), dorsal (20) and distal (21) views. 22. Male palpal tarsal organ. 23. Comb hairs ventrally on male tarsus 4. 24. Male chelicerae, frontal view. 25. Male gonopore. Scale lines: 10 µm (22), 30 µm (23, 25), 100 µm (18 – 21, 24).

FIGURES 26 – 31. Nyikoa limbe n. sp. 26. Female ALS. 27. Male ALS. 28. Male ALS with thick silk line emerging from widened spigot. 29. Epigynum, ventral view. 30. Detail of pore plate. 31. Dorsal view of cleared female internal genitalia. ep, epigynal pockets; pgs, “ piriform gland spigots ”; pp, pore plate. Scale lines: 7 µm (26, 27, 30), 20 µm (28), 100 µm (29, 31).