Cerbalus aravaensis, Levy, Gershom, 2007

Levy, Gershom, 2007, Calommata (Atypidae) and new spider species (Araneae) from Israel, Zootaxa 1551, pp. 1-30 : 17

Cerbalus aravaensis n. sp.

Figs. 42–46

Holotype. adult male from edge of salt marsh, north of En Avrona (694176/284815), Arava Valley, Israel, leg. Uri Shanas, July 28, 2003 ( HUJ 15412), pitfall trap; female paratype with same data.

Etymology. The specific name refers to the type locality.

Description. Carapace yellow, covered by fine white bristles and with broad, deep brown, dorsal median band extending anteriorly to frontal tips of chelicerae. Strong yellow legs gartered with black at articulations and tips. Opisthosoma cream-coloured throughout. AME largest, laterals subequal, PME smallest. Clypeus narrower than diameter of an AME. Chelicerae with three retromarginal teeth.

Male. Measurements (holotype + 10 ɗɗ; holotype listed first): total length 23.5, 18.5–24.0; carapace length 11.5, 9.5–12.0, width 8.5, 7.4–10.0, index 1.35, 1.19–1.31; clypeal index 0.90, 0.70–0.90; leg lengths: I 53.0, 44.7–55.0, II 58.3, 49.0–60.5, III 47.0, 41.2–48.3, IV 49.4, 44.0–52.5; patella-tibia index 1.62, 1.57– 1.81.

Palpus. Very large with mat of dense bristles on upper back of cymbium. Sclerotic tegular division bears a short, thick, mesally pointed, median apophysis ( Figs. 42–44 ). Tibia with one prolateral macroseta and a pointed, retrolateral, black apophysis with light-brown step-like boss at middle ( Figs. 42, 43 ).

Female. Measurements (3 ΨΨ): total length 22.0–26.5; carapace length 10.5–11.5, width 8.5–9.0, index 1.24–1.28; clypeal index 0.91; leg lengths: I 41.0–45.9, II 44.0–51.0, III 35.5–39.5, IV 38.5–43.0; patella-tibia index 1.36–1.52.

Epigynum . Large. Smooth, cream-coloured median platelet posteriorly, at middle, slightly or deeply notched; sides bordered by dark brown raised folds densely covered with bristles ( Fig. 45 ). Inner spermathecae consist of thick, blackish tubes partly hidden under large ovoid, whitish bodies ( Fig. 46 ).

Diagnosis. Cerbalus aravaensis n. sp. resembles C. psammodes Levy by the narrow clypeal region and the light coloured opisthosoma but differs distinctly, also from all other Cerbalus species, by the shape of the peculiar, median apophysis projecting from the male palpal tergum, and by the shape of the inner spermathecae of the female.

Distribution. Israel and Jordan, at the conterminous southern Arava Valley. Records: Israel: Yahel, Lotan , Yotvata, Elifaz , En Avrona. Jordan: West Wadi Sik (709433/326944), Rahma (704084/314071), Qatar area (704388/306210; 702650/306079).

Comments. Cerbalus aravaensis n. sp. with a leg span of 14 cm, exceeds even C. negebensis Levy , and is thus the largest sparassid of the Middle East. Catching these sizeable, sand dwelling, nocturnal spiders was accomplished by the use of deep buckets instead of the usual pitfall traps, and even these were frequently filled to the brim because of heavy sand storms (Uri Shanas, pers. comm.). Cerbalus aravaensis n. sp., apart from sand dunes, inhabits also partly stable sands at the edge of salt marshes. Its retreat in the ground is concealed by a hinged, trap-door like operculum.

Adult females were taken in April and July, and males in July and August. All three Cerbalus species of Israel live in southern arid, extremely hot areas, and yet, albeit nocturnal, are active during July-August, the hottest months in the Middle East. Each of the three species is distributed in a separate area: C. negebensis lives in the stony desert of the Negev ( Levy 1989; 1993), C. psammodes inhabits the loose sands of Haluza, while the newly described C. aravaensis is found in the sands of the Arava, in the Afro-Syrian Rift Valley.

Figures

FIGURES 42 – 44. Cerbalus aravaensis n. sp. ♂, holotype, left palpus. 42. Mesal view. 43. Ventral view. 44. Retrolateral view.

FIGURES 45, 46. Cerbalus aravaensis n. sp. Ψ. 45. Epigynum, ventral view. 46. Spermathecae, dorsal (inner) view.