Macrocheles ovoidalis, Niogret, Jerome & Nicot, Antoine, 2008

Niogret, Jerome & Nicot, Antoine, 2008, Combined approach using morphology and ITS-sequences for description of three new species of Macrocheles (Acari: Macrochelidae), Zootaxa 1873, pp. 39-49 : 44-45

Macrocheles ovoidalis sp. nov.

Type series. Holotype: Female, Gabon, Bakoumba, 1° 79' S, 13° 04' E, equatorial climate, June 2006, 623 m alt., on Stomoxys calcitrans . Paratypes: 3 females, same data as for holotype, deposited in collections of the Muséum National d’Histoire Naturelle de Paris ( France); other paratypes (2 females) same data as for holotype, deposited in the collection of the Laboratoire de Zoogéographie, University of Montpellier, France.

Female. Brown in colour, medium size.

Dorsal shield ( Fig. 3 a). Shield rounded, longer than wide; length 488 ± 53 µm, width 280 ± 8 µm (n = 6); with distinct ornamentation, punctured procurved line, reticular pattern of irregular pentagons or hexagons heavily covered by punctures; polygons less visible in median zone. Shield with 28 pairs of setae; j1 directed forward, expanded and pilose in distal half; z1 smooth, reduced in length; setae j2-6, z1, z5, z6, s1, J2 and J5 simple; S4, S5 and Z4 pilose in distal third; Z5 weakly pilose in distal third; other setae distally pilose.

Ve n t r a l idiosoma ( Fig. 3 b). Tritosternum and peritremes normal for genus. Sternal shield slightly longer than wide; length 104 ± 10 µm, width at level of coxae II 98 ± 4 µm (n = 6); with three pairs of smooth setae and two pairs of elongated pores. Strong globular ornamentations aggregated and forming symmetrical grapelike pattern (19 polygons per side); anterior margin (around first setal insertion) and posterior margin lacking in such an ornamental pattern, with only sparse punctations. Median transverse line, oblique anterior lines, angular line and arched line not visible. Epigynial shield wider than long; 168-171 µm long, 193-197 µm wide; with a pair of setae; shield with strong ornamentation, with several backward-directed arched lines forming a tile-like pattern; four median arched lines crossed by four other arched lines on each side of the shield. Ventri-anal shield wider than long, 74-77 µm long, 111-115 µm wide, covered by dense globular tiles similar to epigynial shield, with eight main clearly visible backward-directled transverse curved lines. Longitudinal and curved lines delimit rectangles covered by globular tiles; with three pairs of pre-anal setae, a pair of para-anal setae and a post-anal seta. Metasternal plates elongate, oval, with a pore and a simple seta.

Gnathosoma . Typical for the M. glaber -group. Chelicerae robust ( Fig. 3 c) pilus dentilis straight; arthrodial brush reaching mid length of movable digit, movable digit with one tooth. Palpi similar to M. glaber . Epistome glaber -like in shape, with smooth lateral lobes and long and pilose central branches. Legs. Setae simple or lightly pilose at the distal end except setae on genu I, tibia and basitarsus IV and tarsi, setae long and thin.

Etymology. The specific name refers to the ovoid body shape of the species.

Figures

FIGURE 3. Macrocheles ovoidalis sp. nov. Female. (a) dorsal shield; (b) ventral idiosoma; (c) epistome; (d) chelicera. Scale bar = 500 Μm for 3 a, 300 Μm for 3 b, 50 Μm for 3 c, 30 Μm for 3 d.