Poachelas, Haddad & Lyle, 2008

Haddad, Charles R. & Lyle, Robin, 2008, Three new genera of tracheline sac spiders from southern Africa (Araneae: Corinnidae), African Invertebrates 49 (2), pp. 37-37 : 65-67

Genus Poachelas gen. n.

Etymology: From the grass family Poaceae , with which these spiders are closely associated, and from the genus Trachelas , to which they are related. Gender masculine.

Type species: Poachelas striatus sp. n.

Diagnosis:This genus can be easily recognised from other trachelines by the pale elongate body, usually with a median abdominal stripe ( Figs 72–75 ), lack of a dorsal scutum in both sexes, darkened anterior tibiae and metatarsi, and ventral leg cusps in known males that also have paired ventral leg spines on the anterior legs. Females lack cusps and may or may not have strong paired ventral leg spines on the anterior tibiae and metatarsi.

Description: Small spiders, 2.63–4.23 mm long; carapace cream or yellow, abdomen with grey median stripe; AER procurved, clypeus height 0.5–0.66× AME diameter; AME slightly smaller than ALE; AME separated by 0.33–0.5× their diameter, AME nearly touching ALE; PER strongly recurved; eyes variable in size, usually subequal; posterior eye interdistances subequal, at least 0.75× PME diameter; chilum single, triangular, weakly sclerotised; cheliceral promargin with three teeth, retromargin with two or three teeth, often on single base; labium trapezoidal; endites straight laterally with distinct serrula ( Fig. 76 ); carapace oval, elongate, widest at midpoint; carapace with slight depression at 0.66× its length, fovea indistinct, posterior margin straight; pleural bars isolated, weakly sclerotised; sternum oval-elongate; precoxal triangles present; intercoxal sclerites present between coxae I and II, reduced between coxae II and III and III and IV; legs I slightly more strongly built than other pairs; patellae I with plv spines ( Fig. 77 ); anterior legs of males strongly spined, with paired ventral spines on tibiae and metatarsi ( Fig. 78 ), and elongate cusps on tibiae, metatarsi and tarsi I, and metatarsi II ( Figs 78–80 ); anterior legs of females strongly spined in P. striatus ( Figs 81, 82 ), arrangement as for males, replaced by erect setae in P. montanus ; cusps absent; tarsi with paired claws and dense claw tufts ( Fig. 83 ); metatarsi III and IV with terminal preening comb ( Fig. 84 ); leg formula 1423 ♂, 4123 ♀; abdomen elongate oval, twice as long as wide; dorsal scutum absent in both sexes; venter without sclerites; male palp with long, narrow, curved RTA ( Figs 85, 86 ); tegulum round, embolus originating distally on tegulum, curling around margins, curving along retrolateral margin of cymbium towards cymbial tip ( Fig. 85 ); female epigyne variable, with copulatory openings situated medially in posterior half of epigyne ( Fig. 87 ); ST II large and situated anteriorly; ST I small, posterolaterally situated.

Species included: P. montanus , P. solitarius and P. striatus (all new).

Key to species of the genus Poachelas gen. n.

1 Males (♂ of P. montanus sp. n. unknown) ............................................................ 2

– Females (♀of P. solitarius sp. n. unknown) ........................................................ 3

2 Median abdominal stripe broad and pale grey ( Fig. 72 ); embolus tip reaching tip of cymbium ( Fig. 91 ); retrolateral tibial apophysis curved in retrolateral view ( Fig. 97 ) ................................................................................................ P. striatus sp. n.

– Median abdominal stripe narrow and black ( Fig. 74 ); embolus tip extending 2/3 the distance from distal end of tegulum to cymbial tip ( Fig. 97 ); retrolateral tibial apophysis straight in retrolateral view ( Fig. 97 ) ....................... P. solitarius sp. n.

3 Anterior legs with strong paired ventral spines on tibiae and metatarsi; epigyne with copulatory openings in broad lip-like ridge ( Fig. 94 ); ST II round, ST I small, oval ( Fig. 95 );>3.0 mm long ....................................................... P. striatus sp. n.

– Anterior legs with erect setae on tibiae and metatarsi; epigyne with small anteromedian hood, copulatory openings in posteriorly directed curved ridges ( Fig. 98 ); ST II large and oval, ST I elongate with rounded posterior lobe ( Fig. 99 ); <3.0 mm long .......................................................................................... P. montanus sp. n.

Figures

Figs 72–75. General habitus of Poachelas gen. n. species: (72, 73) P. striatus sp. n., male, Erfenis Dam Nat. Res., and female, Bloemfontein; (74) P. solitarius sp. n., male, Maleme Rest Camp; (75) P. montanus sp. n., female, Platberg Nat. Res. Scale bars = 1.0 mm.

Figs 76–87. Scanning electron micrographs of Poachelas striatus sp. n.: (76) female, serrula; (77) female, patella, prolateral view; (78) male, leg I, indicating ventral spines (SP) and cusps (CU); (79) male, cusps on metatarsus I; (80) male, metatarsal cusp enlarged; (81) female, tibia I with plv spines missing and rlv spines present; (82) female, tibial spine base; (83) male, tarsal claw and claw tufts; (84) male, metatarsus IV preening comb; (85) male palp, ventral view; (86) male palpal RTA; (87) female, epigyne, ventral view.

Figs 88–95. Poachelas striatus sp. n., male (88–91) and female (92–95): (88, 92) carapace, lateral view; (89, 93) eye region, anterior view; (90, 91) palp, ventral and retrolateral views; (94, 95) female epigyne, ventral and dorsal view. Scale bars: 1.0 mm in Figs 88, 92; 0.1 mm in Figs 89–91, 93–95.

Figs 96–99.(96, 97) Poachelas solitarius sp. n., male palp, ventral and retrolateral views; (98, 99) P. montanus sp. n., female epigyne, ventral and dorsal views. Scale bars = 0.1 mm.