Lamellodectes, Hernandes, Fabio A. & Valim, Michel P., 2014

Hernandes, Fabio A. & Valim, Michel P., 2014, On the identity of two species of Proctophyllodidae (Acari: Astigmata: Analgoidea) described by Herbert F. Berla in Brazil, with a description of Lamellodectes gen. nov. and a new species, Zootaxa 3794 (1), pp. 179-200 : 181-182

Genus Lamellodectes gen. nov.

Type-species: Pterodectes ocelatus Berla, 1960

Description. BOTH SEXES. Moderately elongated pterodectines. Vertical setae ve absent. Idiosomal setae f2 present or absent. Prodorsal shield covering most of the prodorsum, without well developed posterior angles. Scapular shields present, long and narrow. Humeral shields present, well developed. Setae c2 situated anterodorsally on humeral shields. Seta wa set closer to tarsal apex than to la and ra, the latter two setae approximate to each other and situated in basal half of tarsi I, II (in males of L. distinctus sp. nov., seta wa near level of setae la and ra, see Fig. 5 A, B). Seta gT of tibia I in proximal half of segment. Setae cG and mG on genua I, II setiform (these setae may be slightly thicker basally, with filiform apex). Solenidion σ 1 of genu I subequal to solenidion ω 3 on tarsus I. Femora I without ventral crest, femora II with small ventral crest, other segments of these legs without processes or other modifications. Seta sR of trochanter III present; solenidion σ1 of genu III present.

MALE. Epimerites I fused into a narrow V or Y, fused part not connected with epimerites II. Coxal fields I–IV open; epimerites II and IV without extensive sclerotized areas. Opisthosomal lobes very short, posterior margin of lobes roughly rounded. Terminal cleft short, with its anterior end rounded. Setae h3 long setiform, situated on lobar apices. Setae h1 situated anterior to bases of opisthosomal lobes. Setae ps1 filiform, minute. Genital arch with well developed branches, base of genital apparatus posterior to level of trochanters IV; aedeagus sword-shaped. Genital papillae anterior to base of genital apparatus. Pregenital apodeme, paragenital apodemes, genital shield and other sclerotized structures around genital apparatus absent. Setae 4a situated on soft tegument of coxal fields IV. Opisthoventral shields absent. Corolla of adanal suckers with indentations. Adanal shields present, situated anterolateral to adanal suckers. Setae ps3 situated anteromesal to adanal suckers. Setae g and ps3 arranged in longitudinal rectangle. Legs I slightly thicker than legs II. Legs III and IV subequal in size and form. Solenidion φ of tibia IV longer than on tibia III. Tarsus IV without apical claw-like process, setae d and e button-like.

FEMALE. Epimerites I fused into a narrow V. Lobar region of opisthosoma clearly separated from remaining part of opisthosoma; opisthosomal lobes well developed, with long terminal appendages. Hysteronotal shield split dorsally into anterior and lobar shields. Macrosetae h2 with dagger-like basal part and filiform apical part. Epigynum horseshoe-shaped, large. Translobar apodemes present or absent. Legs I slightly thicker and longer than legs II. Legs III, IV subequal in size. Solenidion φ of tibia III longer than on tibia IV.

Etymology. Contraction of lamella, diminutive of lamina (Latin, – plate, leaf, layer), and Pterodectes , the type genus of the Pterodectinae .

Differential diagnosis. The new genus belongs to the tribe Pterodectini and to the Proterothrix group (sensu Mironov 2009), and is most similar to the genus Proterothrix in having an almost complete set of idiosomal setae occurring in pterodectines, solenidion σ present on genu III in both sexes, and genital papillae situated anterior to the genital apparatus which has well-developed genital arch in males. Lamellodectes gen. nov. is distinguished from Proterothrix by the presence of small terminal lamellae in males. In Proterothrix , males have no lamellar projections; at most the terminal or inner margin of opisthosomal lobes is sometimes membranous. Lamellodectes is the only Neotropical genus of Pterodectinae with males having simultaneously a small pair of terminal lamellae and well developed genital arch. In males of Nanopterodectes, the opisthosoma also ends with a small pair of lamellae, but the branches of genital arch are absent (Mironov 2009; Hernandes & Valim 2012).

Figures

FIGURE 5. Lamellodectes distinctus sp. nov., male. A – D—legs I – IV, respectively.