Myiomystax trilineata, 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 : 147-148

Myiomystax trilineata n. gen., n. sp.

( Figs 3 ; 4 ; 5B )

urn:lsid:zoobank.org:act:4BF6B1A7-8DED-4AFA-9184-A51145B25143

TYPE LOCALITY. — Guyane, Mitaraka.

TYPE MATERIAL. — Holotype. French Guiana • ♂; Mitaraka , site MIT-C-RBF2; 02°14’03.4”N, 54°26’53.0”W; 29 m a.s.l.; lowland rainforest; 27.II-6.III.2015; YPT; Marc Pollet leg. (sample code: MITARAKA/125); specimen dissected, mounted on slide; MNHN. Paratypes. French Guiana • 1 ♀; site MIT-C-RBF2; 02°14’03.4”N, 54°26’53.0”W; 29 m a.s.l.; lowland rainforest; 27.II.2015; Marc Pollet leg. (sample code: MITARAKA/018); SW; LACM 340595 • 4 ♂, 2 ♀; same data as holotype; YPT; MNHN (2 ♂, 1 ♀), LACM (2 ♂ LACM 340603-340604 , 1 ♀ LACM 340605 ) • 1 ♂, 2 ♀; site MIT-C-RBF1; 02°14’10.8”N, 54°26’49.5”W; 25 m a.s.l.; lowland rainforest; 27.II-8.III.2015; Marc Pollet leg. (sample code: MITARAKA/133); YPT; MNHN (♂, 1 ♀), LACM (1 ♀ LACM 340606 ) • 9 ♂, 5 ♀; site MIT-C-RBF2; 02°14’03.4”N, 54°26’53.0”W; 29 m a.s.l.; lowland rainforest; 6-10. III.2015; Marc Pollet leg. (sample code: MITARAKA/136); YPT; MNHN (4 ♂, 3 ♀), LACM (5 ♂ LACM 340607-340611 , 2 ♀ LACM 340612-340613 ) • 1 ♀; site MIT-C-RBF2; 02°14’03.4”N, 54°26’53.0”W; 29 m a.s.l.; tropical wet forest (bas fond); 27.II-2. III.2015; Marc Pollet leg. (sample code: MITARAKA/184); SLAM; MNHN • 1 ♀; site different sites near base camp and along trails; 14.III.2015; Julien Touroult & Eddy Poirier leg. (sample code: MITARAKA/191); SLAM; MNHN .

ETYMOLOGY. — The specific epithet is derived form the Latin word “linea”, meaning line, in reference to the three darkly pigmented wing veins present in this species.

DIAGNOSIS. — See above, Myiomystax n. gen.

DISTRIBUTION. — Currently known from multiple localities in the Mitaraka range of French Guiana.

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

DESCRIPTION

Male

Measurements, (N = 4) head width 0.41 mm (0.38-0.44), head height 0.47 mm (0.44-0.48), wing length 2.17 mm (2.08- 2.24), wing width 0.54 mm (0.52-0.56). Head with vertex extended slightly posteriorly, eyebridge comprised of 3 facet rows, contiguous but strongly constricted at median. Frons and clypeus distinctly divided; frontal scar patch bilobed posteriorly, contiguous medially; clypeus elongated laterally, with lateral margins overlapping medial margins of eyes. Antennae: scape cylindrical, about 2.5 times longer than wide; pedicel globular; flagellomeres 1-5 elongate, cylindrical; flagellomeres 6-11 fusiform; flagellomeres 12-14 reduced, bead-like; flagellomere 14 with apical process digitiform, setose, approximately as long as node; all flagellomeres lacking ascoids. Mouthparts extending slightly beyond base of palp segment 1; labellum about as wide as anterior margin of clypeus; palpi conspicuously elongate, with segment 1 hook-like; segment 2 clavate, inflating from base to apex; segment 3 elongate, inflated at midlength; segment 4 inflated apically, capitate; palp segments with clusters of spatulate setae inserted dorsally and ventrally; palps folded behind head at rest. Wing: strongly lanceolate; radial fork positioned slightly distal to apex of CuA; medial fork positioned at the level of apex of CuA; R 5 terminating in C posterior to wing apex; wing veins R 1, R 5 and M 4 pigmented brown, appearing more heavily sclerotized than other wing veins ( Fig. 5B ); costal vein with light pigment between apices of R 1 and R 3, M 1 and M 4; pigmented veins contrasting against other lightly colored wing veins. Male terminalia: bilaterally symmetrical; hypandrium flat, band-like, arched posteriorly, fused with gonocoxites laterally; intersegmental membrane connecting between anterior margin of hypandrium and posterior margin of abdominal segment 8, covering base of ejaculatory apodeme; ejaculatory apodeme dorsoventrally compressed anterolaterally, dome-like at center, articulating ventrally with gonocoxal apodemes, posteriorly with aedeagal sclerites; aedeagus comprised of paired, laterally compressed sclerites, spatulate in lateral view; spatulate sclerites enveloped by tubular membrane; parameres not differentiated from aedeagus; gonostyli tapered, sinuous from base to apex ( Fig. 3D ), digitiform apically, setose, with paired, elongate setae inserted medially near apex ( Figs 3D ; 4A ); gonocoxites glabrous, without setae alveoli ( Figs 3D ; 4A ), cylindrical, about two times as long as wide; gonocoxal apodemes inflated, rounded in dorsoventral view, bulbous in lateral view, linked to subepandrial sclerite anteromedially; subepandrial sclerite narrow, divided medially, with puckered seam at median, with posterolateral arms ribbon-like, linked to base of epandrial claspers; epandrium rectangular along posterior half in dorsoventral view, anterior half narrowing abruptly; epandrial claspers elongate, tapered, curved dorsally from base to apex, with single, spatulate tenaculum inserted dorsoapically.

Female

Measurements, (N = 4) head width 0.44 mm (0.42-0.46), head height 0.41 mm (0.40-0.42), wing length 2.16 mm (2.04-2.36), wing width 0.53 mm (0.52-0.56). Head mostly as in male. Antennae with flagellomeres 1 and 2 elongate, cylindrical, shorter than in male; apical flagellomeres missing in specimens observed. Mouthparts as in male; maxillary palpi more typical of Psychodinae , segments not elongated; palp segment proportions: 1, 1.30, 1, 2.30. Wing venation as in male. Terminalia: cerci conical in ventral view, with ventral surface covered by setulae, numerous setae inserted laterally and ventrally; posterior margin of sternum 8 trilobed, with median lobe wider than flanking lobes; oviduct with microtrichia internally on membrane.

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. 4. — Myiomystax trilineata n. gen., n. sp.:A, male terminalia,lateral view; B, female mouthparts and maxillary palpi,frontal view;C, female terminalia,external structure, ventral view; D, female terminalia, internal structure and egg, ventral view. Abbreviations: see Material and methods. Scale bars: 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