Heliconilla crassa, Dankittipakul & Jocqué & Singtripop, 2012

Dankittipakul, Pakawin, Jocqué, Rudy & Singtripop, Tippawan, 2012, Systematics and biogeography of the spider genus Mallinella Strand, 1906, with descriptions of new species and new genera from Southeast Asia (Araneae, Zodariidae) 3369, Zootaxa 3369 (1), pp. 1-327 : 306

Heliconilla crassa sp. nov.

(Figs 1318, 1374–1376)

Material examined. Holotype: ♂, THAILAND , Surat Thani Province: Ko Tao , 180–370 m, 7–10 July 2005, leg. P.J. Schwendinger ( MHNG, TH–05/04) . Paratypes: 3♂, same data as holotype ( MHNG, TNHM) .

Diagnosis. Heliconilla crassa sp. nov. can be easily distinguished from its congeners by a truncated mesal ramus and an apically flattened lateral ramus of the embolus (Figs 1374–1375); the tegulum is greatly reduced in size (Fig. 1374).

Etymology. The specific epithet refers to the relatively thick embolic base on the male palp (Latin adjective, crassus = solid, thick, heavily build).

Description. Male (holotype). Total length 6.30; prosoma 4.65 long, 3.50 wide. Eye sizes and interdistances: AME 0.12, ALE 0.10, PME 0.06, PLE 0.06, AME–AME 0.06, AME–ALE 0.08, PME–PME 0.08, PME–PLE 0.20; MOQ: 0.26 long, 0.22 anterior width, 0.20 posterior width. Leg measurements: I 11.98 (3.22, 4.06, 2.48, 2.20), II 10.74 (2.92, 3.42, 2.48, 1.90), III 10.54 (2.90, 3.38, 2.48, 1.74), IV 14.54 (3.52, 4.26, 4.10, 2.64).

Coloration. Carapace dark chestnut-brown. Chelicerae dark brown. Sternum dark reddish brown. Legs brown. Opisthosoma sepia.

Palp (Figs 1318, 1374–1376). RTA digitiform, relatively short, margin almost parallel, apex bluntly pointed. Cymbium with very broad cymbial fold, reaching approximately 3/4 of its length. TA with vague basolateral ridge (absent in ventral view). Embolic base aligned in transverse direction; anterior membranous part distinctly narrowed. Embolus broad, originating at 270°, diverging proximally; mesal ramus short and stout; lateral ramus broadest at half its length, gradually tapered towards flattened apex.

Female. Unknown.

Natural history. Heliconilla crassa sp. nov. was collected by means of sifting decomposing organic litter in secondary and evergreen forests on an island where it occurs syntopically with H. thaleri comb. nov.

Distribution. Known only from type locality, an island off the east coast of southern Thailand.