Porrhotegaeidae, 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 : 71

Porrhotegaeidae fam. nov.

Type genus: Porrhotegaeus J. Balogh & Mahunka, 1966, p. 557 .

Diagnosis. Lamellae broad, well developed, ovoid, with free cusps bearing one or two teeth, lacking translamella. Bothridia free, not fused with lamellae. With long blade-like humeral processes extending from lateral margin of notogaster at widest part to point mid-way along lamellae, lateral margin reflexed ventrally; humeral processes lacking lobes posterior of the main anterior structure. Tutorium broad, with a well-developed, curved point. Prodorsum waisted posterior of bothridium. Notogaster U-shaped, surface flat or concave, never convex; margins elevated above level of central notogaster; with eight or nine pairs of long notogastral setae positioned marginally and pointed dorsally. Pedotectum I sub-rectangular; pedotectum II sub-rectangular or lobe-like; discidium pointed. Anterior margin of pedotectum I and epimere I forming straight or curved transverse tectum covering posterior mentum. Circumpedal carina and enantiophyses E4 present; with or without perigenital carinae. Six pairs of genital setae aligned longitudinally, three pairs of adanal setae. Anal plates lozenge-shaped. Pre-anal organ T-shaped. Nymphs with well-developed free lamellar cusps and lateral notogastral setae emerging from long, fine apophyses fused with gastronotum; lateral setae flanked by elongated, flat scales with strongly serrated margins.

Remarks. Porrhotegaeidae is established for Porrhotegaeus because the genus shares few character states with Dudichella and Pterozetes which Luxton (1988a) placed with Porrhotegaeus in the Pterozetidae . The genus clearly does not fit within Eutegaeidae , where it was placed by J. and P. Balogh (1992) and Subías (2004) ( Table 1 ) although it shares with Eutegaeidae the prodorsum markedly waisted posterior of the bothridia. The establishment of a separate family for Porrhotegaeus is justified based on a series of autapomorphies including the broad, ovoid lamellae with pointed, free cusps; the flat or concave surface of the notogaster with a raised margin; the reflexed humeral processes and the long notogastral setae positioned marginally that are curved at their bases and pointed dorsally. Furthermore, the immatures are unique among those known in the Eutegaeoidea in having strongly-developed lamellar cusps projecting beyond the rostrum, and the notogastral setae c 3 and those of the l, h and p series in the nymphs emerge from extremely long, fine apophyses that are part of the gastronotum and which are flanked by elongated, flat scales with strongly serrated margins.