Austrocarabodes pustuloreticulatus, 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 : 107-110

Austrocarabodes pustuloreticulatus sp. n.

( Figs 33–39 )

Material examined. Holotype: Malagasy Republic, Vohimana reserve , primary forest. 17. 04. 2008. Leg. CS . CSUZDI (Afr-996) . 8 paratypes from the same sample. Holotype (1774-HO-09) and 6 paratypes (1774-PO-09) deposited in HNHM , 2 paratypes in MHNG .

Diagnosis. Narrow, elongated body. All dorsal setae short, widely-phylliform. Sensillus gradually dilate, with distinctly barbed, curved distal end. Interlamellar surface pustulate, notogastral surface reticulate. Light spot on humeral region. Epimeral setal formula: 3–1–3–3. Setae 1b conspicuously long. Sternal bor- der with ring-shaped formation. Genitoanal setal formula: 4–1–2–3. Genital, aggenital and anal setae setiform, simple, adanal setae slightly widened, its margin roughened or finely aciculate.

Measurements. Length of body: 439–478 µm, width of body: 208–226 µm.

Prodorsum. Rostrum wide, rounded. Its apical part projecting anteriorly. Lamellae also wide, with small apices laterally, bearing serrate and ciliate, dilated lamellar setae. An indistinct translamella present. Rostral setae phylliform, with 2 veins, arising near to translamella, on the rostral part of prodorsum. Lamellar surface smooth, interlamellar surface covered with ring-shaped alveoli ( Fig. 34 ). Interlamellar setae located clearly on the interbothridial surface, near to the lamellae. They are long, saliciform, aciculate, directed outwards. Sensillus ( Fig. 36 ) short, with distinct asymmetrically curved head. They are also covered with thick barbs asymmetrically.

Notogaster. Elongate. Anterior notogastral margin convex, a pair of very visible, triangle humeral process and a pair of light field visible behind them present. Notogastral surface, except sejugal part, covered by distinct polygonate pattern ( Fig. 35 ). Its lines distinct, thin and simple, composing a closed network. Fourteen pairs of short, well dilate notogastral setae, all nearly equal in size covered with acicules, bearing two veins each.

Lateral part of podosoma ( Fig. 38 ). Tutorium narrow, without true apex. Lateral surface of the prodorsum with 3–4 large spots. Pedotecta I also large, completely covered acetabulum of leg I. Pedotectum II–III small, rounded.

Ventral parts ( Fig. 37 ). Epimeral region with well sclerotised structure, apodemes and borders compose nearly a closed network. Sternal apodema with semicircle formation in the sejugal region. Behind the epimeral borders IV a pair of well-developed longitudinal laths directed backwards, semicircle crests absent. Subcapitulum distinctly foveolate, epimeral surface with weak polygonal pattern. Ventral, genital and anal plates smooth. Epimeral setae conspicuously varying in length, setae 1a, 1c, 2a very short or minute, setae 1b longest of all, setae 3a, 3b, 4a – 4c nearly equal in length. All setae, except the minute ones, well pilose or aciculate. Genital, anal and aggenital setae normal, setiform, adanal ones slightly dilate.

Remarks. The new species is well characterised by the prodorsal and notogastral sculpture, the semicircle formation on sternal borders and the shape of dorsal setae. This combination of characters was hitherto unknown in the genus Austrocarabodes HAMMER, 1966 . A similar polygonate pattern is known in A. lunaris ( BALOGH, 1962) , however, the sensillus is in lunaris is setiform and long (short and dilated in the new species). See also the key of the Austrocarabodes species of Madagascar.

Etymology. Named after the different prodorsal and notogastral sculpture.

IDENTIFICATION KEY TO THE MADAGASCARIAN AUSTROCARABODES HAMMER, 1966 SPECIES

1 (8) Sensillus with well dilated, asymmetrically curved, unilaterally barbed, distinct head

2 (3) Notogastral surface with polygonate sculpture. – Prodorsal surface with pustules A. pustuloreticulatus sp. n.

3 (2) Notogastral surface with small tubercles, pustules or other rounded features

4 (5) Whole notogastral surface covered with pustules. – Anogenital setae large, phylliform, like the notogastral ones A. blancharti sp. n.

5 (4) Notogastral surface covered by pustules or small tubercles ordered in polygonal pattern

6 (7) Two anterior pairs (c 1, c 2) of notogastral setae directed anteriorly. – Notogastral surface with large alveoli located in irregularly positions. Notogastral setae large, phylliform, curved A. armatus sp. n.

7 (6) All notogastral setae equal in direction and shape. – Notogastral surface covered by irregular tubercles and pustules, notogastral setae short and wide A. parapustulatus sp. n.

8 (1) Sensillus long, setiform or hardly dilated medially, symmetrical, recurved dorsally and distinctly pilose

9 (10) Notogastral surface with small tubercles, ordered in polygonal pattern. – Notogastral setae very wide A. mixtus MAHUNKA, 1996

10 (9) Notogastral surface with other ornamentation. Notogastral setae thin

11 (12) Notogastral surface with distinct polygonal pattern. – Anterior notogastral margin strongly convex. Notogastral setae saliciform A. lunaris ( BALOGH, 1962) 12 (11) Notogastral surface pustulate or punctate. – Notogastral setae bacilliform

13 (14) Notogastral surface distinctly tuberculate or pustulate. – Ventral plate with angular crest A. cellularis ( BALOGH, 1962)

14 (13) Notogastral surface punctulate. – Notogastral setae thin. Ventral plate without angular crest A. albidus ( BALOGH, 1960)

Figures

Figs 33–39. Austrocarabodes pustuloreticulatus sp. n.: 33 = body in dorsal view, 34 = setae in, 35 = seta da, 36= sensillus, 37 = body in ventral view, 38 = podosoma in lateral view, 39 = femur III