Compactozetes calderi, Colloff, 2023

Colloff, Matthew J., 2023, The oribatid mite superfamily Eutegaeoidea (Acari, Oribatida), with descriptions of new taxa from Australia and New Caledonia and a re-assessment of genera and families, Zootaxa 5365 (1), pp. 1-93 : 59-60

Compactozetes calderi sp. nov.

( Fig. 30 )

Dimensions. Holotype female length 1,051 μm, breadth 830 μm; paratype female length 1,072 μm, breadth 857 μm. Ratio of prodorsum to total length: 0.4 (holotype).

Description of adult. Prodorsum: rostrum entirely covered by lamellae; rostral setae (ro) relatively long, smooth, curved, only visible in ventral aspect. Lamellae very broad, with reticulate apical microsculpture, anterior margin truncated, concave ( Fig. 30a ), curving ventrally, fused with each other and rostrum; with large paired lateral foramina between lamellae and prodorsum visible in ventral view ( Fig. 30b ), corresponding with lighter, ovoid areas of cuticle on dorsal surface of lamellae. Tutorium with pointed apex, extending beyond margin of lamellae. Massive, curved pedotectum I projecting laterally well beyond margin of prodorsum and anteriorly as far as level of apices of tutorium. Lamellar seta (le) relatively long, stout basally, flagelliform apically. Interlamellar setae (in) short, setiform, smooth, on median margins of lamellae. Bothridia fused with lamellae, projecting slightly beyond posterolateral lamellar margins. Bothridial seta long, bacilliform, with few apical spines. Central region of prodorsum between median lamellar margins and anterior of setae in with area of lighter cuticle, marked by inverted U-shaped margin.

Notogaster: ratio of length to breadth: 0.77; notogaster rounded, convex, smooth. Humeral process with triangular anterior lobe with blunt apex, microsculpture of wavy ridges, extending to level of bothridia, lateral margin undulating and with shorter secondary lobe and small posterior lobe just anterior of setae lm ( Fig. 30a ). Lyrifissures ia and im not visible. With nine pairs of notogastral setae in marginal position; l and h series long, curved, smooth, at least four times longer than p series which are not visible in dorsal aspect.

Ventral aspect: subcapitulum acute, elongated; subcapitular setae h thin, longer than a and m, positioned close to anterior margin of mentum. Epimeral plates diffuse, broadly separated in midline, sub-rectangular to trapezoid, plates III smaller than others; epimeral setation 3-1-2-3; setae relatively short, 4c slightly longer than others ( Fig. 30b ). Pedotectum I (pd I) massive, curved laterally, with sharp, horn-shaped apex extending as far as apex of tutorium; pd II elongated, lobed, extending beyond lateral notogastral margin; discidium broad, lobed, with blunt apex, larger than pd II; perigenital carina and enantiophysis E4 absent. Ventral plate ovoid, markedly broader than long. Genital and anal plates separated by distance of same length as genital plates; genital plates 130 µm long, with six pairs of short setae, g 1 same length as others, g 5 displaced laterally; three pairs of short adanal setae; lyrifissure iad in para-anal position, moderately close to margin of anal plate. Anal plates lozenge-shaped, 170 µm long. Pre-anal organ (po) oval.

Etymology. This species is named for its co-collector, Dr. Andrew A. Calder, coleopterist and my former colleague at the Australian National Insect Collection, Canberra, who collected many of the Berlesate samples from which I have described new oribatid species.

Type designation, material examined and locality data. Holotype female, ANIC accession no. 53-1075 , ANIC 754, Nothofagus and Sassafras ( Atherosperma moschatum ) litter, Nothofagus moorei forest, Cobark Forest Park, Barrington Tops, New South Wales, 31°59’S, 151°49’E, coll. T. Weir and A. Calder, 15.xi.1981. Paratype: female, ANIC accession no. 53-1076, ANIC 749, litter, closed Eucalyptus forest, Barrington Tops National Park, Gloucester Road., 30°04’S, 151°41’E, T. Weir and A. Calder, 12-14.ix.1981.

Diagnosis. Compactozetes calderi can be distinguished from other species in the genus by the following combination of characters: (1) the flagelliform lamellar setae; (2) the bacilliform bothridial seta with apical spinules; (3) the lighter area of cuticle on the central prodorsum marked anteriorly by an inverted U-shaped margin; (4) the humeral process consisting of a blunt, triangular anterior lobe with a posterior indentation, a second protruding lobe and then a third, smaller, lobe; (5) the relatively long, curved notogastral setae of the l and h series; (6) the very large, broad, curved pedotectum I with a sharp, pointed apex.

Remarks. Compactozetes calderi belongs to the ‘zeugus’ species group. It shares with C. goongerah sp. nov. (cf. below) the relatively long notogastral setae of the l and h series (though those of C. calderi are longer), the large, blade-shaped pedotectum II and discidium and the triangular blunt anterior lobe of the humeral process. However, the humeral process of the latter species has four lobes rather than three (of which the hindmost is longer and more prominent than the second), a smaller pedotectum I with markedly concave lateral margins, expanded apices to the bothridial setae and very long setae 4c.

Figures

FIGURE 30. Compactozetes calderi sp. nov., adult (a) dorsal aspect; (b) ventral aspect. Scale bar = 200 μm.