Rhampsinitus vittatus Lawrence 1931

Taylor, Christopher K., 2017, Notes on Phalangiidae (Arachnida: Opiliones) of southern Africa with description of new species and comments on within-species variation, Zootaxa 4272 (2), pp. 236-250 : 247

Rhampsinitus vittatus Lawrence 1931

Fig. 7

Rhampsinitus vittatus Lawrence 1931: 482 –483, fig. 70.

Rhampsinitus silvaticus Lawrence 1931: 491 –493, fig. 76 syn. n.

Material examined (all CAS). 6 males, 3 juveniles, Harkerville State Forest , 19 km E Knysna, Western Cape Province, 34°03’S 23°14’E, el. 240 m, indigenous forest, 11–13.xii.1996, C. E. Griswold ; 11 males, 3 females, 4 juveniles, Kranshoek , 20 km E Knysna, Western Cape Province, 34°05’S 23°14’E, el. 180 m, forest, 13.xii.1996, C. E. Griswold.

Description. Male (fig. 7). As for Lawrence (1931), with the following additions: Carapace with anterior margin unarmed except for single median denticle. Penis (figs 7c–e) with blunt hatchet-shaped glans, distal profile truncate, point of reflexion of posterior margin in lateral view in distal half; shaft thick, slightly broadening towards distal end to form moderate ‘spoon’ with weakly sclerotised margins, base moderately bulbous.

Notes. Rhampsinitus vittatus was described by Lawrence (1931) from two males collected at Sir Lowry’s Pass in western South Africa, near Cape Town . The specimens examined herein are similar to Lawrence’s description in cheliceral and pedipalp morphology and overall armature, and are likely to represent the same species. Though the current specimens’ collection locality is some distance from the type locality, Lotz (2009) listed records of this species from this region and further east, and it is possible that Rhampsinitus vittatus occurs along much of the coastal region of South Africa .

This species has a distinctive male genital morphology compared to other Rhampsinitus , the majority of which have a glans with a narrow, blade-like posterior edge and an acute terminus near the origin of the stylus (as found in R. conjunctidens and R. regulus described herein; Kauri 1961; Staręga 1984, 2009; Schönhofer 2008). The glans of R. vittatus has a rounder posterior edge and a broadly truncate terminus (fig. 5d). Kauri (1961) illustrated the same genital morphology for R. silvaticus Lawrence 1931 , a species originally described from Knysna and supposed to differ from R. vittatus in having fewer denticles on the pedipalp and less enlarged male chelicerae. The specimens examined herein, however, exhibit variation in these characters between individuals, with the degree of pedipalpal denticulation and cheliceral inflation correlating with overall body size. As such, R. vittatus and R. silvaticus are synonymised herein.

Figures

FIGURE 7. Rhampsinitus vittatus Lawrence 1931, male. A: Body, dorsal view; B: anterior part of body, lateral view; C: penis, left lateral view; D: penis, dorsal view; E: glans, left lateral view.