Jocquestus, Lyle & Haddad, 2018

Lyle, Robin & Haddad, Charles R., 2018, Jocquestus, a new genus of trachelid sac spiders from the Afrotropical Region (Arachnida: Araneae), Zootaxa 4471 (2), pp. 309-333 : 310-312

Genus Jocquestus gen. nov.

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Type species. Trachelas schenkeli Lessert, 1923

Etymology. The genus name is a patronym in honour of Rudy Jocqué, former head of the Invertebrate Section of the Royal Museum for Central Africa in Tervuren, Belgium, in recognition of his vast contributions to the

systematics of spiders, particularly the Zodariidae , Corinnidae and Ctenidae of the Afrotropical Region, and to arachnology in general. Gender masculine.

Diagnosis. Jocquestus gen. nov. can be recognized from other genera of smaller trachelid spiders, particularly Trachelas and the Afrotropical Fuchiba , Fuchibotulus and Planochelas , by males having blunt ventral cusps on the tibiae and metatarsi of leg I, and sometimes also on tarsi I and/or tibiae and metatarsi II ( Figs 7 , 30–32 ), which are absent in females ( Fig. 8 ). Males of Jocquestus gen. nov. share with the Eurasian genus Paratrachelas the ventral cusps at least on leg I of males, but can be distinguished by the presence of a large RPA, and absence or presence of a short blunt RTA on the male palpal tibia (e.g. Figs 37 , 49 ). In Paratrachelas the RPA is entirely absent, while the RTA is strongly developed (see Kovblyuk & Nadolny 2009). Females are very distinct amongst these aforementioned genera of smaller trachelines by the heavily sclerotized epigastric plate, with broad, generally obliquely-directed epigynal ridges containing lateral copulatory openings ( Fig. 40 ).

Description. Small spiders, 2.20–4.10 mm in length. Carapace: orange-brown, red-brown or dark brown ( Figs 1, 2 , 9–20 ); broadly oval with narrow eye region, widest at midpoint ( Figs 1, 2 , 21 ); dome-shaped in lateral profile, elevated from clypeus to behind posterior eyes, highest at midpoint, with steeper slope in posterior third ( Figs 3, 4 , 22 ); surface finely wrinkled, sparsely covered in short straight setae with finely granulate bases ( Figs 21–24 ); posterior margin nearly straight, very slightly concave ( Fig. 21 ); clypeus height approximately equal to AME diameter ( Fig. 23 ). Eyes: AER slightly recurved in dorsal view ( Fig. 21 ), procurved in anterior view, AME smaller than ALE ( Fig. 23 ); AME closer to ALE than to each other; PER recurved in dorsal view, PLE very slightly larger than PME ( Fig. 24 ), or equal in diameter; PME closer to each other than to PLE; all eyes surrounded by black rings; chilum single, retracted, triangular, rounded or with slight notch distally; cheliceral promargin and retromargin each with one to three teeth; cheliceral escort seta (sensu Ramírez 2014) present in front of fang base ( Fig. 25 ); labium trapezoidal; endites depressed laterally, with distinct serrula ( Figs 26, 27 ). Sternum and associated sclerites: sternum shield-shaped, strongly rebordered ( Figs 5, 6 ); pleural bars isolated from each other and intercoxal sclerites; precoxal triangles present; intercoxal sclerites present between all coxal pairs. Legs: legs I, II and IV nearly equal in length, leg formula usually 1243, rarely 2143, 4123 or 4132; anterior legs more strongly built than posteriors, particularly in males ( Figs 1, 2 , 9–20 ); legs without spines, all segments covered with short fine setae, with scattered long erect setae on femora and tibiae I ( Figs 7, 8 ); femora I swollen, strongly constricted proximally, more distinctly in males ( Fig. 7 ) than females ( Fig. 8 ); patellar indentation narrow, with broad lyriform organ at proximal end ( Figs 28, 29 ); anterior tibiae, metatarsi and tarsi with ventral cusps in males ( Figs 7 , 30–32 ), absent in females ( Fig. 8 ), with pseudotenent setae ventrally on tarsi only ( Fig. 33 ); metatarsi III and IV with dense terminal preening brush; tarsal claws short, paired, claw tuft plates with dense claw tufts comprising tenant setae ( Fig. 33 ); tarsi with sparse chemosensory setae ( Fig. 34 ) and trichobothria ( Fig. 35 ) dorsally; tarsal organ only very slightly elevated from surface, with faint ridges and oval opening ( Fig. 36 ). Abdomen: broadly oval, tapering posteriorly, grey dorsally, occasionally with cream markings ( Figs 1, 2 , 9–20 ); male with dorsal scutum covering entire abdomen ( Fig. 1 ), only present in females of J. schenkeli comb. nov. ( Fig. 2 ) and J. roeweri comb. nov.; dorsum sparsely covered in short fine setae in males, denser in females; two pairs of weakly sclerotized dorsal sigilla present; ventrally with strongly sclerotised epigyne and booklungs, separated by narrow membranous strips; post-epigastric sclerites broad in males, narrow in females; two paired lines of tiny sclerites between epigastric furrow and spinnerets ( Figs 5, 6 ); inframamillary sclerite absent. Genitalia: male palp with large RPA ( Figs 37, 39 ), RTA absent or small; palpal femur with shallow longitudinal ventral ridge; palpal patella with lyriform organ at base of RPA on retrolateral side ( Figs 37, 38 ); cymbium oval proximally, narrowed distally; tegulum oval, embolus originating retrolaterally or proximally, curving around prolateral margin of tegulum, with tip near distal end of cymbium (e.g. Fig. 39 ); conductor and median apophysis absent, except narrow conductor present in J. griswoldi sp. nov. and J. obliquus sp. nov.; female epigyne usually strongly sclerotised, with copulatory openings situated posterolaterally in oblique ( Fig. 40 ) or curved ridges, entering directly into large comma-shaped, elongate or oval anterior ST II, with narrow ducts leading to small, posteriorly situated ST I.

Figures

FIGURES 1–8. Digital microscope photographs of somatic morphology of Jocquestus schenkeli (Lessert, 1923) comb. nov. male (1, 3, 5, 7) and female (2, 4, 6, 8). 1, 2. Habitus, dorsal view; 3, 4. Same, lateral view; 5, 6. Same, ventral view; 7, 8. Leg I, prolateral view. Scale bars = 1.0 mm.

FIGURES 21–32. Scanning electron micrographs of Jocquestus schenkeli (Lessert, 1923) comb. nov. male (21, 24, 28–32) and female (22, 23, 25–27): 21. Carapace, dorsal view; 22. Same, lateral view; 23. Eyes, anterior view; 24. Same, posterior view; 25. Distal end of chelicera, indicating cheliceral escort seta (CES) in front of fang; 26. Serrula; 27. Detail of serrula teeth; 28. Patella III, patellar indentation (PI); 29. Same, detail of lyriform organ at proximal end of PI; 30. Tibia I cusp; 31. Metatarsus I cusps; 32. Tarsus I cusp.

FIGURES 37–40. Scanning electron micrographs of Jocquestus schenkeli (Lessert, 1923) comb. nov. male (37–39) and female (40): 37. Right palp, retrolateral view, rectangle surrounding lyriform organ at distal end of patella at base of patellar apophysis; 38. Enlargement of lyriform organ; 39. Left palp, ventral view; 40. Epigyne, ventral view.

FIGURES 47–51. Jocquestus griswoldi sp. nov. male (47–49) and J. harrisi sp. nov. female (50, 51): 47. Schematic representation of cusp arrangement on legs I and II; 48. Left palp, ventral view; 49. Same, retrolateral view; 50. Epigyne, ventral view; 51. Vulva, dorsal view. Scale bars = 0.1 mm.

FIGURES 9–20. Digital microscope photographs of the dorsal habitus of Jocquestus gen. nov. species. 9. J. capensis sp. nov., male; 10. Same, female; 11. J. griswoldi sp. nov., male; 12. J. harrisi sp. nov., female; 13. J. incurvus sp. nov., male; 14. Same, female; 15. J. obliquus sp. nov., male; 16. Same, female; 17. J. roeweri (Lawrence, 1938) comb. nov., male; 18. Same, female; 19. J. schenkeli (Lessert, 1923) comb. nov., male; 20. Same, female.

FIGURES 33–36. Scanning electron micrographs of Jocquestus schenkeli (Lessert, 1923) comb. nov. male tarsus IV (33, 34) and female tarsus I (35, 36): 33. Distal end of tarsus, including claw tufts and modified setae; 34. Detail of chemosensory seta; 35. Trichobothrium base; 36. Tarsal organ. Abbreviations: CS—chemosensory seta; FS—feathery seta; PsTe—pseudotenent seta; Te—tenent seta; TR—trichobothrium.