Orchestina gibbotibialis, Henrard & Jocqué, 2012

Henrard, Arnaud & Jocqué, Rudy, 2012, 3284, Zootaxa 3284, pp. 1-104 : 55-57

Orchestina gibbotibialis new species

Figures 299–317, 606

TYPE: Holotype Male : Kenya, Gatamayu forest, canopy, 0.96666°, 36.70000°, Jan. 18, 1999 to Jan. 23, 1999, Wagner T., ( ZFMK PBI _OON 33846).

ETYMOLOGY: The species name is derived from the combination of ‘gibbosus’ (swollen) and ‘tibia’ (leg) referring to the remarkably swollen base of tibia I in the male.

DIAGNOSIS: Both males and females of O. gibbbotibialis have conspicuous dark radiating striae on the sternum and a pair of pale spots on the labium ( Figs. 300, 306). The male is further recognized by the prolateral swelling at the base of tibia ( Figs. 303, 304) and the long slender setae on the labium ( Fig. 316, 317). The female is characterized by the long, narrow, cylindrical AUS, recurved in lateral view ( Figs. 312, 313) but appearing as a straight line ventrally.

MALE (PBI_OON_0033846). Total length 1.12. CEPHALOTHORAX: Carapace ( Figs. 299, 301, 302) brown, broadly oval in dorsal view (CW/CL ≈ 0.92), pars cephalica strongly elevated in lateral view, anteriorly narrowed to between 0.5 and 0.75 times its maximum width, Clypeus vertical in lateral view. Eyes ALE-PME: touching, PME circular; PLE-PME separated by less than PME radius. Sternum ( Fig. 300) as long as wide, yellow-brown, anterior margin with semicircular depression in the middle half, anterior part strongly bulging; posterior margin extending posteriorly beyond anterior edges of coxae IV as single extension, pattern with tiny dark sepia spots, forming dark stripes radiating from anterior half of sternum; setae abundant, evenly scattered. Mouthparts: Chelicerae, endites and labium pale orange. Chelicerae straight, fang straight; setae dark. Labium ( Figs. 315–317) triangular, anterior margin indented at middle, same as sternum in sclerotization, with tiny sepia spots delimiting two oval, adjacent areas in porsterior part ( Fig. 300); with 6 or more setae on anterior margin, subdistal region provided anteriorly with group of five needle like setae, medilally with one pair of thin symmetric flattened setae in the centre, followed by one pair of thin asymmetric flattened setae, positioned in a slightly oblique longitudinal row. Endites ( Fig. 315) serrula absent, anteromedian tip unmodified, same as sternum in sclerotization. ABDOMEN ( Figs. 299, 300, 302): globular; dorsum soft portions pale white, with gray netlike pattern. Book lung covers large, ovoid. Pedicel scutum absent, but abdomen not extending anterior of pedicel. LEGS: yellow; patella plus tibia I near as long as carapace (TL/CL ≈ 1.05), tibiae I proximal part with strong prolateral outgrowth ( Figs. 303, 304) provided with group of setae. Leg spines absent. GENITALIA: Palp ( Figs. 309–311) proximal segments pale orange; patella attached to tibia sub-basally; tibia two to three times as wide as femur, dorsal side domed; cymbium pale orange, without distal patch of setae; bulb pale orange, stout, tapering apically; embolus dark, slender, needle shaped, as long as bulbus, at almost right angle with long axis of bulbus.

FEMALE (PBI_OON_0033843). As in male except as noted. Total length 1.44. CEPHALOTHORAX: Carapace ( Figs. 305, 307, 308): broadly oval in dorsal view (CW/CL ≈ 0.81) Clypeus sloping forward in lateral view. Mouthparts: Chelicerae, endites and labium orange-brown. Endites serrula present in single row. ABDOMEN: without long posterior extension, rounded posteriorly. Spinnerets: ALS with five spigots, PMS with two spigots, PLS with three spigots. GENITALIA ( Figs. 312–314): Ventral view: AUS long, thin, appearing straight in dorsoventral views, inverted u-shaped in lateral view, distal half in ventral position, bears a pair of short Pr. Dorsal view: dorsolateral extensions (Ex) distally strongly widened; AUS tubular, consisting of dorsal and ventral parts, surpassing extensions by twice their length, curved over 180°; its ventral part provided with short transverse lateral protrusions (Pr) situated at half of the total length; ARe not visible in our preparations but probably fused with AUS anteriorly; posterior receptaculum absent.

MATERIAL EXAMINED: KENYA: Central Province : Gatamayu , Kikuyu Escarpment: Gatamayu Forest, canopy, -0.96666°, 36.70000°, Jan. 02, 1999, Wagner T., 1♀ ( MRAC 228798 PBI _OON 16788); as previous, Feb. 01, 1999, 1♂ ( MRAC 228797 PBI _OON 16789). as previous, Feb. 01, 1999, 1♀ paratype ( ZFMK PBI _OON 33147) ; as previous, Feb. 01, 1999, 1♂ paratype ( ZFMK PBI _OON 33643) ; as previous, Feb. 01, 1999, 2♀ paratypes ( ZFMK PBI _OON 33644) ; as previous, Jan. 18, 1999 to Jan. 23, 1999, 1♀ paratype ( ZFMK PBI _OON 33842) ; as previous, Jan. 18, 1999 to Jan. 23, 1999, 1♀ paratype ( ZFMK PBI _OON 33843) ; as previous, 1♀ paratype ( ZFMK PBI _OON 33844) ; as previous, 1♀ paratype ( ZFMK PBI _OON 33845) ; as previous, 1♂ paratype ( ZFMK PBI _OON 33847) ; as previous, 1♂ paratype ( ZFMK PBI _OON 33848) ; as previous, Feb. 01, 1999, 1♀ paratype ( ZFMK PBI _OON 33899) . Mt Kenya , 1.5 km S of Castle Forest Lodge, 1985 m, -0.38333°, 37.30000°, mountain forest, beating, Apr. 21, 2004, Jocqué, Warui, VandenSpiegel, 1♂ ( MRAC 215124 PBI _OON 29254) .

DISTRIBUTION: Known from mountain forest in Central Kenya ( Fig. 606).