Jocquestus obliquus

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: 322-323

publication ID

https://doi.org/10.11646/zootaxa.4471.2.4

publication LSID

lsid:zoobank.org:pub:691AD8B9-27BB-40E6-A3D8-C3D17DA38B0B

persistent identifier

http://treatment.plazi.org/id/0772878D-041C-FFE4-FF45-F9CFFDBB6D98

treatment provided by

Plazi

scientific name

Jocquestus obliquus
status

sp. nov.

Jocquestus obliquus  sp. nov.

urn:lsid:zoobank.org:act:67CA925C-D192-4CF2-AD2D-C29C16B2E6CA

Figs 15, 16View FIGURES 9–20, 56–60View FIGURES 56–60

Etymology. This species name is derived from the Latin for “oblique”, referring to the slanting, 45° angle of the epigynal ridges of the female epigyne.

Diagnosis. Males of J. obliquus  sp. nov. can be easily recognized by the uniquely coiled embolus ( Fig. 57View FIGURES 56–60), which is linear in all other Jocquestus  species. The female can be recognised by the comma-shaped ST II that are narrower at their base than anteriorly, resulting in a clear median space separating their proximal parts ( Fig. 59View FIGURES 56–60). Further, the ducts linking ST I and II are placed halfway between the midline and lateral margins of the ST ( Fig. 60View FIGURES 56–60), as opposed to medially in congeners.

Male (paratype, Mkomazi Game Reserve, OUMNH). Measurements: CL 1.56, CW 1.13, AL 1.71, AW 1.15, TL 3.24, FL 0.06, SL 0.78, SW 0.63, AME–AME 0.03, AME–ALE 0.02, ALE–ALE 0.22, PME–PME 0.07, PME–PLE 0.06, PLE–PLE 0.39.

Length of leg segments (sequence from femur to tarsus, and total): I 0.94 + 0.44 + 0.65 + 0.52 + 0.40 = 2.95; II 0.87 + 0.42 + 0.63 + 0.56 + 0.38 = 2.86; III 0.70 + 0.38 + 0.48 + 0.56 + 0.27 = 2.39; IV 0.82 + 0.44 + 0.63 + 0.74 + 0.30 = 2.93.

Carapace orange-brown, with faint black mottling ( Fig. 15View FIGURES 9–20); surface finely wrinkled, with sparse short, fine setae; fovea short, broad, slightly darker than carapace, at two thirds CL. All eyes surrounded by black rings; AER procurved; AME slightly smaller than ALE; clypeus height slightly greater than AME diameter; AME separated by distance slightly less than half their diameter; AME separated from ALE by distance equal to one-quarter AME diameter; PERAbout PER recurved, PLE slightly larger than PME; PME separated by distance slightly less than their diameter; PME separated from PLE by distance slightly less than PME diameter. Chelicerae orange-brown, anterior surface with scattered long, fine setae; two promarginal teeth, distal tooth largest; two smaller retromarginal teeth, proximal tooth largest. Sternum yellow-brown, with faint black mottling, darker along border; surface smooth, with scattered short, fine setae. Abdomen dark grey, with two paired cream markings, first subtriangular pair anteriorly, second transverse pair anterior to midpoint ( Fig. 15View FIGURES 9–20); two pairs of yellow-brown sigilla, first pair at one-third abdomen length, second pair at midpoint of abdomen; surface sparsely covered with short, fine setae. Legs I to IV with femora orange-brown, paler proximally, with grey mottling dorsally and laterally; patellae to metatarsi I–IV yellow-brown, with faint grey mottling; tarsi uniform orange-brown; all segments covered with short, fine setae; relatively dense ventral scopulae on distal metatarsi and tarsi legs III and IV; leg spination: tibiae: I plv 8 rlv 3 cusps; metatarsi: I plv 8 cusps; tarsi: I plv 1 cusp ( Fig. 56View FIGURES 56–60). Palp orange-brown; RPA subquadrangular in retrolateral view, ventral end slightly pointed; tibia with small rounded retrolateral-dorsal RTA, with small sharp projection on its dorsal surface; embolus originating prolaterally on tegulum, parallel-sided long its length, distal half forming broad coil ending near cymbium tip; embolus associated with narrow membranous conductor, originating prolaterally on tegulum near embolus base ( Figs 57, 58View FIGURES 56–60).

Female (holotype, Mkomazi Game Reserve, MRACAbout MRAC 211323). Measurements: CL 1.47–1.55, CW 1.14– 1.15, AL 1.49–1.90, AW 1.08–1.25, TL 2.96–3.60, FL 0.04–0.05, SL 0.78–0.85, SW 0.61–0.68, AME–AME 0.03, AME–ALE 0.03, ALE–ALE 0.25, PME–PME 0.08, PME–PLE 0.08, PLE–PLE 0.43.

Length of leg segments (sequence from femur to tarsus, and total): I 0.97 + 0.43 + 0.70 + 0.55 + 0.48 = 3.13; II 0.93 + 0.43 + 0.65 + 0.60 + 0.43 = 3.04; III 0.73 + 0.40 + 0.45 + 0.58 + 0.30 = 2.46; IV 0.90 + 0.43 + 0.70 + 0.78 + 0.35 = 3.16.

Carapace reddish-brown ( Fig. 16View FIGURES 9–20); surface finely granulate, covered with short fine setae; fovea short, indistinct, slightly darker than carapace, at two thirds CL; ocular region brown; AER slightly recurved, almost straight; AME and ALE equal in size; clypeus height approximately equal to AME diameter; AME separated by distance equal to 0.7 their diameter; AME separated from ALE by distance equal to 0.4 AME diameter; PERAbout PER recurved, PLE slightly larger than PME; PME separated by distance slightly larger than their diameter; PME separated from PLE by distance equal to 1.4 PME diameter. Chelicerae brown, anterior surface with sparse long, fine setae; two promarginal teeth, distal tooth largest; two retromarginal teeth, proximal tooth largest. Sternum pale brown, darker towards borders; surface smooth, with scattered short, fine setae. Abdomen dark grey, with two pairs of pale yellow sigilla, anterior and posterior to midpoint of abdomen ( Fig. 16View FIGURES 9–20). Legs I to IV uniform brown, femora darker than other segments; relatively dense ventral scopulae on metatarsi and tarsi of all legs, more prominent on legs III and IV; regular leg spines, cusps absent. Other characters as for male. Epigyne weakly sclerotised; epigynal ridges and CO at 45° angle to epigastric fold, CO situated laterally; large ST II connected with lateral entrance ducts, with folded median ducts connecting ST I and ST II; ST I bilobed when examined dorsally ( Figs 59, 60View FIGURES 56–60).

Type material. Holotype: ♀: TANZANIA: Mkomazi Game Reserve , near Dindira Dam, 04°00'S, 38°00'E, leg. A. Russell-Smith, 25.I.1996 (in gall on Acacia drepanolobium  ) ( MRAC 211323View Materials).GoogleMaps 

Paratypes: TANZANIA: Mkomazi Game Reserve , 03°55'S, 37°48'E, leg. G.C. Mc Gavin, 9.IV.1995 (canopy fogging 2/28, Combretum molle  ), 1♀ ( OUMNH)GoogleMaps  ; same data but canopy fogging 2/30, Combretum molle  , 1♂ ( OUMNH)GoogleMaps  .

Distribution. Known only from the type locality ( Fig. 70View FIGURE 70).

Habitat and biology. An arboreal species collected from Vachellia drepanolobium  and Combretum molle  in savanna habitats in northern Tanzania.

PER

City Museum

MRAC

Mus�e Royal de l�Afrique Centrale