Ossinissa justoi ( Wunderlich 1992 ) Wunderlich, 1992

Dimitrov, Dimitar & Ribera, Carles, 2005, Description of Ossinissa, a new pholcid genus from the Canary Islands (Araneae: Pholcidae), Zootaxa 982, pp. 1-13 : 8-9

Ossinissa justoi ( Wunderlich 1992) new combination

Figs. 1–29

Spermophorides justoi Wunderlich 1992: 329 , figs. 207–209

Material examined. — Canary Islands, El Hierro: Cueva de Don Justo: 2 female paratypes, 18 April 1984 ( SMF 39763, 37193). 1 male, 1 female, 15 April 1984, J. L. Martin ( CCRUB 3517­140, 3518­140); 2 females from the same locality, 6 November 1992, C. Ribera ( CCRUB 3519­140, 3520­140); 2 females, 14 September 2000, GIET (Grupo de Investigaciones Espeleológicas de Tenerife) ( CCRUB 4557­171); 4 females, 1 juvenile, 27 November 2000, GIET ( CCRUB 4558­171, 4559­171); 2 females, 29 January 2000, GIET ( CCRUB 4560­171); 1 male, 1 female, 6 October 2000, GIET ( CCRUB 4563­171, 4561­ 171); 4 females, 1 sub adult male, 1 juvenile, 31 January 2000, GIET ( CCRUB 4562­171). Canary Islands, El Hierro: Cueva de los Pocitos: 2 females, 25 September 2000, GIET ( CCRUB 4554­171); 1 female, 8 October 2000, GIET ( CCRUB 4555­171); 1 female, 15 October 2000, GIET ( CCRUB 4556­171).

Diagnosis. — This species is the only member of Ossinissa new genus known at present. Consequently, diagnosis is difficult. However, on the basis of our knowledge on pholcid taxonomy, we can say that this species is characterized by the shape of the apophyses of the procursus; the shape of the uncus and the shape of the appendix of the genital bulb. The most important character of the female is the shape of the valval ridge and the position of the two pore plates in the vulva.

Measurements. — Male: Prosoma 0.73 wide, 0.74 long; opisthosoma 0.83 wide, 1.22 long, maximum height 0.50; total body length 1.96. Leg I: 15.0 (femur 4.2 + patella 0.2 + tibia 4.4 + metatarsus 5.1 + tarsus 1.1); leg II: 10.8 (2.9 + 0.2 + 2.9 + 3.8 + 1.0); leg III: tarsus and metatarsus missing (2.4 + 0.2 + 2.2); leg IV: 12.0 (3.4 + 0.2 + 2.9 + 4.6 + 0.9). Palp: 2.8 (femur 0.7 + patella 0.4 + tibia 1.1 + tarsus 0.6), procursus 1.0. Female: Prosoma 0.73 wide, 0.83 long; opisthosoma 1.47 wide, 1.81 long, maximum height 1.47; total body length 2.64. Leg I: 18.1 (femur 4.9 + patella 0.3 + tibia 4.9 + metatarsus 6.3 + tarsus 1.7); leg II: 12.3 (3.5 + 0.3 + 3.2 + 4.2 + 1.1); leg III: 9.5 (2.7 + 0.3 + 2.3 + 3.4 + 0.8); leg IV: 13.8 (4.1 + 0.3 + 3.8 + 4.6 + 1.0). Palp 1.2 (femur 0.5 + patella 0.1 + tibia 0.3 + tarsus 0.3).

Description of the male. — Prosoma pale yellow, well­marked fovea and almost undistinguishable junction between head and thoracic region. Ocular area ( Fig. 10 ) elevated and close to the center of prosoma. Eight eyes surrounded by area with darker pigmentation. ALE, PME and PLE on two cylindrical stems. All eyes strongly reduced, especially AME. A bunch of long hairs placed between the stems. Sternum yellowish. Chelicerae brownish ( Figs. 3 , 17), with dark distal apophyses. Proximolateral apophyses smaller close to the end of the clypeus. Distal apophyses cylindrical, apically with three small darker modified hairs ( Fig. 9 ). Legs long, slightly darker. Palp as in Figs. 7–8, 12 , 14 and 16, trochanter with long retrolateral apophysis, femur cylindrical with ventral bulge bearing a small keel. Procursus characteristic ( Figs. 2, 4, 11 , 24), robust, brown. Distal part of the procursus about two times wider than its base. Procursus concave the genital bulb. In the last third, an elliptical incision defines a dorso­retrolateral apophysis. Apophysis short, fingerlike and with smooth limits. Procursus terminates with irregularly serrated membrane. Area just beneath the dorsal incision semi­transparent and thinner than rest of procursus. Procursus located dorsally, with few thick and relatively short hairs. Uncus ( Figs. 1, 5 , 20) well developed. Shape of the uncus and its granulation are characteristic and very useful for diagnosis. Embolus as in Fig. 30 . Opisthosoma cylindrical with same color as prosoma. Spinnerets as in Figs. 26–29 .

Re­description of the female. — All characters as in male except: chelicerae without apophyses and with a lighter pigmentation. Arrangement and size of eyes as in male but stems of lateral triads much shorter (Fig. 18). Hairs between the stems with regular size. Opisthosoma globular and higher than in male. Epigynum (Figs. 19, 23) elevated. Ventrally epigynum with tiny, almost transparent, triangular plate. Plate of epigynum with two dark zones laterally. Some parts of the vulva can be observed externally. Vulva as in Fig. 16.

Distribution. –— Only known form in the Cueva de Don Justo and Cueva de los Pocitos, El Hierro Island, Canary Islands, Spain.

Figures

FIGURES 1 – 13. Ossinissa justoi new combination, male. 1. Uncus, retrolateral; 2. Apex of the procursus, retrolateral; 3. Chelicerae, frontal; 4. Procursus, retrolateral; 5. Uncus, dorso­retrolateral; 6. Tarsal organ, lateral; 7. Palp, dorso­retrolateral; 8. Palp with procursus, dorsal; 9. Distal apophyses of the chelicerae, fronto­lateral; 10. Ocular area, frontal; 11. Procursus, ventral; 12. Male palp, prolateral; 13. Tarsal organ, fronto­lateral. Scale bars: 1 – 5, 10 – 11: 100 µm; 7 – 8, 12: 200 µm; 4: 50 µm; 13: 40 µm; 6: 20 µm; 9: 10 µm.

FIGURES 25 – 29. Ossinissa justoi new combination, female. 25. Opisthosoma, lateral; 26. Anterior lateral spinnerets, ventral; 27. Ocular area, dorsal; 28. Spinnerets, ventral; 29. Posterior median spinnerets, ventral. Scale bars: 25: 500 µm; 26: 20 µm; 27: 100 µm; 29: 10 µm; 28: 50 µm.

FIGURES 30 – 39. Ossinissa justoi new combination, male. Bulbal projections (arrow indicates embolus), dorso­prolateral. Figures 31, 33, 38. Pholcus ornatus, male: 31. Spinnerets, ventral; 33. Gonopore, ventral; 38. Male palp, prolateral. Figures 32, 35 – 36. Pholcus fuerteventurensis, male: 32. Spinnerets, ventral; 35. Gonopore, ventral; 36. Male palp, prolateral. Figures 34, 37, 39. Pholcus gomerae, male: 34. Gonopore, ventral; 37. Spinnerets, ventral; 39. Male palp, ventro­prolateral. Scale bars: 30, 33 – 34: 100 µm; 31 – 32, 36 – 37, 39: 200 µm; 38: 500 µm; 35: 50 µm.