Scirites Bishop & Crosby 1938

Dupérré, Nadine & Paquin, Pierre, 2007, Revision of the North American genus Scirites (Araneae, Linyphiidae), Zootaxa 1460, pp. 47-58 : 49

Scirites Bishop & Crosby 1938

In their characterization of this North American genus, Bishop & Crosby (1938) mention that it is closely related to Scolopembolus Bishop & Crosby 1938 having the same type of embolic division, but differs by the male palpal tibia and by the anterior metatarsi bearing a row of long curved spines. In the present paper, we did not support nor reject this hypothesis, but we suspect that this relationship is valid based on superficial morphology. We were however able to establish close relationship with Tapinocyba Simon 1884 , Ceratinops Banks 1905 and Parapelecopsis Wunderlich 1992 . Scirites is now composed of two species, both distinguished by a rather simple embolic division, the absence of embolic membrane, and the presence of a distinct row of 7 curved megaspines on the metatarsus I of the male.

Diagnosis.— Males of the genus Scirites differ from all other erigonines by the presence of a row of seven curved megaspines on metatarsus I. Females show no clear characters allowing differentiation from most erigonines, particularly from the North American genera Tapinocyba , and Cheniseo Bishop & Crosby 1935 . They however differ from the closely related Ceratinops by the longitudinal opening of the ventral plate (see Paquin & Dupérré 2003, figs 858, 862, 866).

Description.— Small spiders (~ 1.14–1.49) with the following characters: Tm I 0.52–0.62, Tm IV absent, tibial spination 1 1 1 1. Median tracheal trunk branched into bundles of small tracheoles without taenidia. Presence of 7 curved megaspines on metatarsus I of male ( Fig. 1 ). The male carapace is raised in the eye region and somewhat flat (Figs 2, 10). Male palp with a rather simple embolic division consisting of a tailpiece, radix and embolus (Figs 3, 4, 11, 12). Tegulum rather large in ventral view, protegulum large and bearing protegular papillae (Figs 3, 11). Distal suprategular apophysis basal part sclerotized changing to membranous, with or without marginal suprategular apophysis (Figs 4, 12). Paracymbium variable (Figs 5, 13). Palpal tibia variable (Figs 6, 14). Female epigynal plate somewhat rectangular, spermathecae rounded, well separated, situated each side of the junction of ventral plate and dorsal plate (Figs 7, 8, 15, 16).

Figures

FIGURES 1. Scirites. 1, male metatarsus I, lateral view; 2 – 9 Scirites pectinatus 2, male cephalothorax, lateral view, 3, palpus of male, ventral view, 4, expanded male palpus, schematic lateral view, 5, palpus of male, lateral view, 6, palpal tibia of male, dorsal view, 7, epigynum, ventral view, 8, spermathecae, ventral view, 9, spermathecae, dorsal view. 1 – 3, 5 scale bar = 0.1; 4, 6 – 9 scale bar = 0.05. CD copulatory ducts; DP dorsal plate; DSA distal suprategular apophysis; E embolus; FD fertilization ducts; F fundus; MSA marginal suprategular apophysis; P paracymbium; PT protegulum; PTP protegular papillae; PTA pedipalpal tibial apophysis; R radix; S spermathecae; SPT suprategulum; T tegulum; TP tailpiece; VP ventral plate.