Hymenozetes csuzdii, Mahunka, 2009

Mahunka, S., 2009, Oribatid Mites From The Vohimana Reserve (Madagascar) (Acari: Oribatida) I., Acta Zoologica Academiae Scientiarum Hungaricae 55 (2), pp. 89-122 : 116

Hymenozetes csuzdii sp. n.

( Figs 50–52 )

Material examined. Holotype: Malagasy Republic, Vohimana Reserve , primary forest. 17. 04.

2008. Leg. CS. CSUZDI (Afr-996). Holotype (1777-HO-09) in HNHM.

Diagnosis. Rostrum straight, without apex, rostral setae arising laterally. Lamellae wide, with sharp lateral cusp, its median part thin, framed by a curved transversal lath basally. All prodorsal setae flagellate. Sensillus setiform, directed posteriorly. Anterior notogastral margin convex, pteromorphae tongue-shaped, rounded. Seven pairs of notogastral setae short, wide with strong spines. Sejugal apodemes well, all other much weaker developed. Epimeral and genital setae simple, mostly smooth. Shape of the adanal setae similar to the notogastral ones.

Measurements. Length of body: 385 µm, width of body: 330 µm.

Prodorsum. Rostral part very wide, without apex, straight anteriorly. Rostral setae arising on small tubercles, very far from each other. Lamellae very wide, with overlapping two parts, covering the whole prodorsal surface. Its inner apex absent, straight anteriorly, outer apex well-developed, curved inwards ( Fig. 50 ). A small basal part of the prodorsum behind transversal band seems to be free. Insertion of lamellar setae covered by the lamellae, interlamellar setae flagellate, arise on transversal band. Sensillus directed outwards and backwards, its distal end slightly dilated, unilaterally distinctly barbed.

Notogaster. Anterior notogastral margin convex, pteromorphs without teeth laterally. Dorsal surface of notogaster smooth. Nine pairs of notogastral setae present, eight pairs of them very thick, only setae la thinner than the others. All setae spiniform covered by long spines or barbs, like a Christmas-tree ( Fig. 50 ). Posteromarginal setae very short, hardly observable.

Lateral part of podosoma. Tutorium very large, with rounded apex ( Fig. 52 ). Its surface with short wrinkles or ribs anteriorly. Pedotecta I and discidium very large. Pteromorpha linguliform, long, rounded distally.

Ventral parts ( Fig. 51 ). Epimeral region except the posterior border (bo. 4) without typical apodemes or borders. Epimeral borders (bo. 4) a wide transversal band, in front of the genital aperture, bearing a pair of well-developed protuberances near to the genital plates. All epimeral setae thin and simple, their length varying, setae 1a, 1c, 2a and 4c very short, all others much longer.

Remarks. The new species is well characterised first of all by the shape of the notogastral setae and by the absence of the median apex of lamellae. On the basis of the Christmas-tree-shaped notogastral setae, the new species is closest to Hymenozetes verticillatus MAHUNKA, 1997 , however, the notogastral setae of the new species are much shorter than in H. verticillatus . See also the key for Hymenozetes BALOGH, 1962 species.

Etymology. I dedicate the new species to my friend Dr. CSABA CSUZDI, the curator of the earthworm collection of the Hungarian Natural History Museum and professor of the Eötvös Loránd University, Budapest, who collected many very interesting soil samples over the world.

Figures

Figs 50–52. Hymenozetes csuzdii sp. n.: 50 = body in dorsal view, 51 = body in ventral view, 52 = podosoma in lateral view