Dolichognatha mandibularis (Thorell)

Smith, Helen M., 2008, Synonymy of Homalopoltys (Araneae: Araneidae) with the genus Dolichognatha (Araneae: Tetragnathidae) and descriptions of two new species, Zootaxa 1775, pp. 1-24 : 18-19

Dolichognatha mandibularis (Thorell)

Figs 54–60

Paraebius mandibularis Thorell 1894: 44 . Holotype ♂, Sumatra, Lampong. In NHRM, examined. Dolichognatha m. Levi 1981: 277.

Comment. It was initially thought that the male of D. mandibularis (from Sumatra) might pair with D. albida (from Sri Lanka and Thailand) as the short and broad palpal conformation is closest to that of D. deelemanae . However, in general appearance the male D. mandibularis ( Figs 54–58 ) is more similar to males of D. incanescens and D. raveni , with a relatively low carapace, similar eye characteristics, and apparently, no macroseta on the prolateral face of the anterior femora. More specimens are required to resolve this issue and for the time being both species are recognised.

Diagnosis. Male. Palpal bulbus short and rounded, palpal tibia distinctly longer than wide, MEA broad distally ( Figs 59, 60 ).

Female. Unknown.

Description. Male (holotype). Carapace ( Figs 54, 57, 58 ): length 0.86, width 0.67, height 0.29; caput not strongly humped, pear-shaped in dorsal view with caput clearly differentiated. Chelicerae ( Fig. 54, 57 ): cheliceral ledge absent or chelicerae may be pushed up so ledge hidden by carapace; two distinct promarginal cheliceral teeth and one large intermediate, three smaller retromarginal teeth plus basal mound. Labium: with anterior hooked spur. Sternum: concave (but indented by damage). Eyes ( Figs 54, 57, 58 ). AME: 0.10, PME: 0.075, ALE: 0.075, PLE: 0.06, AME–AME: 0.02, AME–ALE: 0.04, PME–PME: 0.02, PME–PLE: 0.04, ALE–PLE: 0.01; no reflective tapeta visible. Legs. I: 3.57, II: 3.06, III: 1.63, IV: 1.94; almost all macrosetae missing, no indication of any prolateral macrosetal bases. Abdomen ( Figs 55, 56 ): length 1.14, width 0.59; apex rounded; post-genital mound indistinct (holotype abdomen is separate from opisthosoma and rather damaged). Male palpus: ( Figs 59, 60 ): palpal femur 0.27× carapace length; patella without macroseta, tibia c. 2× as long as wide; embolus tapering; MEA squat, strongly spoon-shaped distally; conductor, embolus and apophysis all more compact than in D. incanescens ; bulbus short and rounded, width: length = 1:1.5. Colour in alcohol: almost entirely creamy-white and in parts semi translucent; PME with hint of black around margins; faint trace of trident-shaped mark on dorsal carapace ( Fig. 58 ).

Distribution. Dolichognatha mandibularis is recorded only from the type locality in Sumatra.

Figures

FIGURES 54 – 60. Dolichognatha mandibularis male (holotype). 54, prosoma, lateral. 55, 56, abdomen lateral, dorsal. 57, carapace and chelicerae, frontal. 58, carapace, dorsal. 59, 60, male palpal organ, ventral, retrolateral. Scale lines 0.5 mm for somatic parts, 0.1 mm for genitalia.