Copidognathus xaixaiensis, Proches, 2002

Prochesë, Së Erban, 2002, New species of Copidognathinae (Acari: Halacaridae) from southern Africa, Journal of Natural History 36 (8), pp. 999-1007 : 1000-1002

Copidognathus xaixaiensis sp. nov.

( figure 2 )

Material. ( BMNH(E)2001-14 ) One male HOLOTYPE, from the middle littoral rocks on the breakwater wall facing the resort in Xai-Xai ( Mozambique), collected in December 1997, leg. D. J. Marshall.

Male. Idiosoma 265 μm long and 160 μm wide.

Dorsum. All plates with polygonal reticulation. AD 50 μm long and 60 μm wide, with ds-1 positioned posterior of centre; reticulation restricted to the central-posterior part. Anterior margin of AD rounded. OC 45 μm long and 40 μm wide, with one large cornea and ds-2 at the anterior end; the existence of a second cornea is not obvious. The posterior end of OC protruding and reaching to the trochanter of leg III; reticulation restricted to the anterior half. PD 175 μm long and 100 μm wide, not extending beyond the anterior margin of OC. ds-3 to ds-5 evenly placed along each median costa; lateral costae not obvious. The reticulation covers the whole surface, although more pronounced in the anterior third, where the pattern is generally hexagonal. In the posterior part the polygons have various shapes, but are generally more elongated ( figure 2A ). Meshes of reticulation not subdivided, size 4-10 μm ( figure 2I ).

Venter. All plates smooth. AE 100 μm long and 125 μm wide, with three pairs of ventral setae. PE 125 μm long, with one dorsal and three ventral setae. GA 120 μm long and 90 μm wide ( figure 2B ).

Male genitalia. Located at the posterior extremity of GA, surrounded by numerous perigenital setae (extremely fi ne and di ffi cult to count). Genital opening with four pairs of fi ne subgenital setae, two anterior and two posterior.

Gnathosoma. Gnathosoma 110 μm long and 55 μm wide, with smooth cuticle. Rostrum triangular, palpi strongly elongated. Distal palp segment with a whorl of three long basal setae; no apical setae were identi fi ed ( figure 2C ).

Legs. Leg I longer and more robust than other legs. Chaetotaxy, from trochanter to tibia: leg I, 1, 2, 5, 4, 7; leg II, 1, 2, 5, 4, 7; leg III, 1, 2, 2, 3, 5; leg IV, 0, 2, 2, 3, 5. Medial setae on tibiae (two on legs I, II; one on legs III, IV) thickened, but not clearly bipectinated. Lateral setae on genu and tibia II long, on genu and tibia I extremely long, longer then corresponding tarsi ( figure 2D -G ). Claws with a welldeveloped comb and long, pointed tips ( figure 2H ).

Female and juvenile stages. Unknown.

Etymology. This species is named after the collecting locality, Xai-Xai (pronounce Shye-Shye) in Mozambique.

Remarks. This species belongs to the Copidognathus tricorneatus group, which has been reviewed by Bartsch (1997b). Among the species of the group, it is similar to Copidognathus tricorneatus (Viets, 1938) in having large meshes in the reticulation of PD, medial costae not reaching the anterior margin of this plate, and triangular rostrum, with rostral sulcus extending to the base of the second palp segment. It has however a very characteristic OC, with no obvious second cornea, and ds- 1 in the inner corner. Unlike in any species of this group, the lateral setae on the genu and tibia of leg I are unusually long. A similar feature occurs in the unrelated species Copidognathus venustus Bartsch, 1977 .

Figures

FIG. 2. Copidognathus xaixaiensis sp. nov. (male): (A) idiosoma, dorsal view, (B) idiosoma, ventral view (bar: 100μm), (C) gnathosoma, dorsal view (bar: 50 μm), (D) leg I, medial view, (E) leg II, medial view, (F) leg III, lateral view, (G) leg IV lateral view (bar: 100 μm), (H) tarsus III (bar: 50 μm), (I) reticulation from the anterior third of AD (bar: 10 μm).