Ketambea acuta, Tanasevitch, Andrei V., 2017

Tanasevitch, Andrei V., 2017, New species and new records of linyphiid spiders from the Indo-Malayan Region (Araneae, Linyphiidae), Zootaxa 4227 (3), pp. 325-346 : 335-336

Ketambea acuta new species

Figs 30–36 , 39–42

Holotype male ( MHNG), THAILAND, Lamphun Province, Mae Tha Distr. , Doi Khuntan N.P., 800 m a.s.l.; 23.IX.1994 ; P. Schwendinger leg. Paratypes. 1 male, 1 female (MHNG), collected together with the holotype. 1 male ( MHNG), Lamphun Province, Mae, Tha Distr., Doi Khuntan National Park , 700 m a.s.l.; 22.XI.1994; P. Schwendinger leg . 1 male ( SMF), MYANMAR , southern Chin State, above Kampetlet, below Mountain Oasis Resort , 21°11’49.5”N 94°02’25.0”E, 1716 m a.s.l., secondary forest, by hand, at night; 15.V.2014 ; P. Jäger leg. 1 female ( SMF), same locality, at night, by hand; 17.V.2014 ; P. Jäger leg.

Type material examined. Male holotype of Ketambea rostrata Millidge & Russell-Smith, 1992 (MHNG), from northern Sumatra.

Etymology. The specific name is a Latin adjective that means “pointed, needle-shaped”, referring to the shape of the lower lobe of the anterior apophysis of the convector in the male palp. Diagnosis. The new species is very similar to K. rostrata Millidge & Russell-Smith, 1992 , known from northern Sumatra ( Millidge & Russell-Smith 1992), and differs by the much longer outgrowth on the proximal part of the convector, and the absence of a pointed process (AUL in Fig. 37 ) on the upper lobe of the anterior apophysis of the convector (cp. Figs 31, 34 , 39, 40 and Fig. 37 ). The female of K. acuta is distinguished by the wide (versus thin in K. rostrata ) septum which divides the epigynal aperture into two parts, as well as by the oval (versus triangular in K. rostrata ) aperture, and the absence of two pockets anteriorly, while in K. rostrata the lateral walls of the epigynum bend towards each other, converging together anteriorly and forming two small pockets.

Description. Male paratype from Doi Khuntan N.P. Rather large Linyphiinae , total length 3.05. Carapace 1.40 long, 1.05 wide, pale brown. Chelicerae 0.65. long, stridulatory furrows well-developed. Legs pale brown, ends of segments darkened. Leg I 5.90 long (1.60+1.50+0.45+1.50+0.85), IV 4.45 long (1.20+0.35+1.00+1.25+0.65). Chaetotaxy. FeI: 1-2-0-0, II-IV: 1-0-0-0; TiI: 2-1-1-0; II: 2-0-1-0, III: 2-0-0-1, IV: 2-0-0-1; MtI-II: 0-0-0-0, MtIII- IV: 1-0-0-0. TmI 0.26. Metatarsi IV without trichobothrium. Palp ( Figs 31, 34 , 39–41 ): Tibia very short, with a group of slightly curved spines arranged in a row. Cymbium without posterodorsal outgrowth(s). Paracymbium very small, its distal part curved, thread-like. Embolic division with a large, flat, strongly sclerotized convector, ending up with an apophysis divided into two lobes: lower lobe long, pointed, stylet-shaped; upper one flat, eggshaped. Embolus long, coiled, its radical part small, well-sclerotized. Median membrane a massive, long, flocculent tissue. Abdomen 1.70 long, 1.00 wide, dorsal pattern as in Fig. 30 .

Female paratype from Doi Khuntan N.P. Total length 3.01. Carapace 1.20 long, 0.95 wide. Chelicerae 0.60 long. Leg I 5.43 long (1.45+0.40+1.35+1.43+0.80), IV 4.60 long (1.35+0.35+1.00+1.20+0.70). TmI 0.24. Abdomen 2.00 long, 1.30 wide, dorsal and ventral patterns as in Fig. 32 and Fig. 33 , respectively. Epigynum ( Figs 33, 35 ): aperture oval, septum relatively wide, dividing aperture into two parts. Posterior median plate wide, with a small protuberance in the middle. Vulva ( Figs 36 , 42 ): seminal ducts very thick, each making two loops. Leg coloration and chaetotaxy as in male.

Distribution. Thailand and Myanmar .

Figures

FIGURES 30 – 38. Ketambea acuta n. sp., male holotype (30, 31) and female paratype (32 – 36) from Doi Khuntan N. P.; K. rostrata Millidge & Russell-Smith, 1992, male holotype, MHNG (37); Plectembolus quadriflectus Millidge & Russell-Smith, 1992 (38), male from Maxwell Hill. 30, 32, Habitus. 31, 34, 37, 38, Right palp, retrolateral view. 33, Abdomen, ventral view. 35, Epigynum, ventral view. 36, Vulvae, dorsal view. Note: LLC in Fig. 37 is probably broken. Scale bars: 30, 32, 35, 36; 33, 0.5 mm; 31, 34, 37, 38, 0.1 mm.

FIGURES 39 – 42. Ketambea acuta n. sp., male and female paratypes from Doi Khuntan N. P. 39, 40, Right palp, retrolateral and prolateral views, respectively. 41, Embolic division. 36, Vulvae, dorsal view. Scale bar: 0.1 mm.