Myiomystax, Curler, 2020

Curler, Gregory, 2020, Descriptions of two new genera of Maruinini (Diptera, Psychodidae, Psychodinae) from the Mitaraka range of French Guiana, Zoosystema 42 (10), pp. 139-149 : 144-147

Genus Myiomystax n. gen.

urn:lsid:zoobank.org:act:510873DE-6E58-4A95-9A5C-1D311DC38A70

TYPE SPECIES. — Myiomystax trilineata n. gen., n. sp.

ILLUSTRATIONS. — Wing: Fig. 3A ; Head: Fig. 3B ; Male genitalia: Fig. 3 C-D.

ETYMOLOGY. — This genus name is derived from the Latin “myia”, meaning fly and “mystax”, meaning mustache, in reference to the maxillary palps of the male. Before treating the specimens with KOH, the setose palps of male M. trilineata n. gen., n. sp. gave the appearance of the fly having a prominent mustache.

DIAGNOSIS. — Male head: antennal flagellomeres 1-5 elongate, cylindrical; all flagellomeres lacking ascoids; clypeus elongate, expanded laterally, with lateral margins overlapping medial margins of eyes; palpi conspicuously elongate, with segment 1 hook-like, segment 4 inflated apically, capitate; palp segments with clusters of spatulate setae inserted dorsally and ventrally; palps folded behind head at rest. Male terminalia: bilaterally symmetrical; gonocoxites glabrous, without setae alveoli; aedeagal sclerites paired, laterally compressed, spatulate. Female head: maxillary palpi not elongated. Female terminalia: posterior margin of sternum 8 trilobed, with median lobe wider than flanking lobes; oviduct with microtrichia internally on membrane.

DISTRIBUTION. — Myiomystax n. gen. is currently known only from the Mitaraka range of French Guiana.

HABITAT. — Little information regarding specific habitat is available; however, all specimens were collected in lowland rainforest.

REMARKS

In contrast to Polletomyia n. gen., the relatively large size and light coloration of Myiomystax n. gen. make it possible to easily differentiate them in samples containing many psychodid genera. Moreover, while both genera have lanceolate wings, the latter is more distinctive due to several veins being darkly pigmented ( Fig. 5 ). The unique wing of Myiomystax n. gen. also makes it easy to associate males and females of this genus. It remains to be determined whether these characteristics of the wing will be present in the wings of congeners, if any are discovered. Although less important compared to those of Polletomyia n. gen., accurate diagnosis of this genus is still dependent on examination of slidemounted male terminalia.

Myiomystax n. gen. males have a bilaterally symmetrical terminalia, with an aedeagus that extends as an open-close mechanism, much like Polletomyia n. gen. and Maruina . However, they differ from the other genera by having paired aedeagal sclerites as opposed to two pairs (as in Polletomyia n. gen.) or multiple aedeagal spines (as in Maruina ). Myiomystax n. gen. males are also unique among these genera in that their gonocoxites lack setae.

DESCRIPTION

See below, Myiomystax trilineata n. gen., n. sp.

Figures

FIG. 3. — Myiomystax trilineata n. gen., n. sp.: A, wing; B, male head, frontal view; C, male epandrium, proctiger and epandrial claspers, dorsal view; D, male terminalia, epandrium removed, dorsal view. Abbreviations: see Material and methods. Scale bars: A, 0.5 mm; B, 0.25 mm; C-D, 0.1 mm.

FIG. 5. — Photomicrographs of male wings: A, Polletomyia subulata n. gen., n. sp.; B, Myiomystax trilineata n. gen., n. sp. Scale bars: 0.5 mm