Austrocarabodes lateoalveolatus, 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 : 102-104

Austrocarabodes lateoalveolatus sp. n.

( Figs 27–29 )

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

2008. Leg. CS. CSUZDI (Afr-996). Holotype (1772-HO-09) in HNHM.

Diagnosis. Rostrum widely conical. Lamellae normal, their cusps wide, bearing spiniform, serrated lamellar setae. Rostral setae narrow, saliciform, curved medially. Interlamellar setae long, saliciform. Interlamellar region with indistinct pattern, covered by secretion layer. Sensillus long, setiform, with recurved distal end, covered by short barbs. Notogaster surface covered by irregular secretion layer and granules. Under this layer some larger alveoli, composing a posteromarginal group, medially. Fourteen pairs of long, phylliform, narrow setae, except setae on posteromarginal position, all long and asymmetrically T-shaped. Apodemes mostly well-developed, longitudinal and semicircle ribs present along the genital aperture. Epimeral setae, except inner ones, long, setiform. Anogenital setal formula 4–1–2–3. Genital setae very long, simple, aggenital setae similar to them. Adanal setae slightly dilated, like notogastral ones. Anterior adanal setae in preanal position, lyrifissures iad located very near to them, also anteriorly.

Measurements. Length of body: 450 µm, width of body: 231 µm.

Prodorsum. Covered by irregular, partly torn secretion layer. Rostral part widely conical, lamellae narrow, with wide, blunt apices bearing spiniform, unilaterally spinose lamellar setae. Translamella present, well-developed, rostral setae phylliform, curved inwards, arising in front of translamella. Interlamellar surface with irregular pattern may consists of secretion. Under secretions layer light spots (maculae) observable ( Fig. 27 ). A transversal crest present basally. Interlamellar setae long, narrowly-phylliform, with one median vein, directed backwards and outwards. Sensillus long, setiform, distinctly pilose, recurved dorsally.

Notogaster. Whole part covered by secretion layer consisting of large and small granules, un- der this layer a group of large alveoli observable in the posteromedian surface. Fourteen pairs of narrow, phylliform notogastral setae present, their basal part bearing a short, elongate extension, reaching over their insertion ( Fig. 27 ). Among them ten pairs of setae much longer than remaining ones in posteromarginal position. All setae with one median vein, their margin finely roughened.

Lateral part of podosoma ( Fig. 29 ). Tutorium bifurcate, its upper ribs directed to the sensillus. Surface of the pedotectum I smooth.

Ventral parts ( Fig. 28 ). Apodemes and epimeral borders except sternal one, well-developed, sternal apodema reduced anteriorly. Connecting with bo. 4 a pair of well sclerotised ribs running longitudinally, ending in semicircle transversal crest. Epimeral surface partly ornamented by irregular pattern consisting of mostly rounded fields. Epimeral setae different in length, setae 1a, 1c, 2a and 3a minute or represent only their alveoli, others conspicuously long and thin, setiform. Setae 1b longest of all. Ventral plate with hardly observable, irregular pattern, consisting of round alveoli. Genital and anal plates smooth, genital setae conspicuously long and fine, aggenital setae very long, setiform, anal setae much shorter than aggenital ones. Aggenital setae leaf shaped, similar to notogastral ones, setae ad 3 located in preanal position, near to the very long lyrifissures iad.

Remarks. The new species is well characterised by the setiform, recurved sensillus, the form of the setae and the notogastral sculpture. The covered posteromedian alveoli on the notogaster are unique in this species group. See also the key of the Madagascarian species of the genus Austrocarabodes HAMMER, 1966 .

Etymology. Named after the group of the concealed alveoli in posteromedian position of the notogaster.

Figures

Figs 27–29. Austrocarabodes lateoalveolatus sp. n.: 27 = body in dorsal view, 28 = body in ventral view, 29 = podosoma in lateral view