Pteramerus clypeatus, Mahunka, 2010

Mahunka, Sándor, 2010, Two new species of Ameroidea (Acari: Oribatida) from Madagascar, Zootaxa 2631 (1), pp. 62-68 : 65-68

Pteramerus clypeatus sp. nov.

( Figs 7–17 )

Diagnosis. Body and legs partly covered by cerotegument. Prodorsal surface without costulae or other comparable structure. A pair of marginal spine present. Pedotecta I very large, round, pedotecta II also larger than usually. Sensillus long, filiform. Dorsosejugal furrow absent. Ten pairs of setiform notogastral setae, arising nearly in marginal rows longitudinally. Except sejugal apodeme all others weakly developed, short. Epimeral setae varying in length, setae 1c longest. Neotrichy on ventral plate present. Six pairs of genital setae arising in longitudinal rows. All legs monodactylous. Trochanter of leg IV with dorsoventral blade-like crest, its margin without serrated border. Dorsal end of trochanter bearing a very large and long spine.

Measurements. Length of body: 285–302 µm, width of body: 153–165 µm.

Prodorsum. Prodorsum (also whole body) very wide, rostral part triangular. Rostral apex blunt at tip. Rostral setae arising marginally on small tubercles. Prodorsal surface with a pair of short lateral crest bearing a thick, short spine ( Fig. 7 ). Lamellar setae located in anterior part of prodorsum, medially near to each other, far from the very short, slightly dilated interlamellar ones. Bothridium small, opened dorsally, horny-shaped, sensillus very long, thin, filiform.

Notogaster. Dorsosejugal furrow absent, a pair of hardly observable, triangular humeral enantiophysis present. Ten pairs of notogastral setae present, arranged in longitudinal lines, along the lateral margin. Setae c 2 shorter than la and lm. Setae p shortest of all Fig. 13 ). Distance between setae h 1, h 2 and h 3 much smaller than between setae la and lm. All setae smooth.

Lateral part of podosoma. Pedotecta I and II round ( Figs 11, 12 , 14 ), pedotectum I with undulate and striated edge. Tutorium absent.

Ventral parts. Ventral surface smooth. Mentotectum as shown in Fig. 17 . Apodemes of epimeral region hardly observable, except ap. sej. Enantiophyses S not observable. Epimeral setae varying in length, setae 1c longest of all, setae 1a and 2a shortest of all. Aggenital and adanal neotrichy, on ventral plate eight pairs of setae present ( Figs 8 , 15 ). Six pairs of genital setae inserted in longitudinal rows. Lyrifissures iad visible, near to anterior corner of anal aperture.

Legs. All legs monodactylous. Trochanter IV with a thin, blade-like formation, with a long, spiniform distal spine ( Figs 9–10 , 16 ).

Remarks. Pteramerus clypeatus sp. n. is the second described species of the genus. It is distinguishable from the type species ( P. draco Balogh, 1962 ) by the largeness and form of pedotecta I–II, and by the form of trochanter IV. A comparison with the type of Balogh species was not possible, because it could not be found in his collection.

Material examined. Holotype: Malagasy Republic, Toamasina Province. Maromizaha forest . 26. August 1998. Leg. Dr. T. Pócs (9890) (Afr-923)). 14 paratypes from the same sample . Holotype (1785-HO-10) and 12 paratypes (1785-PO-10) deposited in the HNHM, 2 paratype in MHNG. Etymology. The name refers to the form of the large, shield–shape pedotecta I–II .

Figures

FIGURES 7–12. Pteramerus clypeatus n. sp.: 7. body in dorsal view; 8. body in ventral view; 9. leg IV; 10. distal end of tochanter IV; 11. pedotecta I–II in lateral view; 12. body in lateral view.

FIGURES 13–17. Pteramerus clypeatus n. sp.: 13. body in dorsal view, 14. body in lateral view, 15. epimeral and ventral plates, 16. body in lateral view, 17. gnathosoma and leg I.