Haloscatella Mathis, 1979

Costa, Daniel N. R., Mathis, Wayne N., Marinoni, Luciane & Sepúlveda, Tatiana A., 2024, Phylogeny and taxonomy of the shore-fly tribe Scatellini (Diptera: Ephydridae: Ephydrinae), Zoologia (e 23100) 41, pp. 1-35 : 13-14

Haloscatella Mathis, 1979

Figs 9 , 32, 33, 40–43

Haloscatella Mathis 1979b: 6 (as a subgenus of Lamproscatella ; feminine). Type species: Lamproscatella arichaeta Mathis 1979a , original designation. – Olafsson 1991: 42 [revised status]. – Mathis and Zatwarnicki 1995: 255–256 [world catalog]. – Mathis et al. 2004: 4–18 [ New Zealand fauna].

Diagnosis. Haloscatella is distinguished from other genera of Scatellini by the following combination of characters: anterodorsal corner of anepisternum with one strong seta curved; parafacial margin lacking row of setulae near parafacial; eye conspicuously wider than high, usually obliquely oriented; insertion of posterior notopleural setae distinctly elevated above level of anterior seta; prescutellar acrostichal seta longer than other acrostichal setae; and female ventral receptacle lacking operculum.

Some Haloscatella similar to Lamproscatella , can be differentiated by the following combination of characters: cinereous, densely microtomentose species; frontal vitta with small setulae towards anterior margin; vestiture of frontal vitta usually microtomentose; posterior notopleural seta inserted at distinctly higher level than anterior seta; medial scutellar seta half the length of apical seta.

Description. Small to moderately small shore flies, body length 1.30–2.90 mm; generally cinereous species.

Head: Frontal vitta generally dull, usually densely microtomentose; small setulae towards anterior margin of frontal vitta; long lateroclinate fronto-orbital setae 2. Antenna short; pedicel with strong seta ventrally and dorsally; basal flagellomere brown; arista macropubescent. Face conspicuously protruding, with an interfoveal, dorsal hump; facial setae conspicuous, 1–3 lateral facial setae curved laterodorsally. Eye usually wider than high, ob1iquely oriented to general plane of head; gena usually medium to high; a row of setulae at the ventral margin of gena, without a distinct genal seta.

Thorax ( Fig. 9 ): Mesonotum cinereous to brown, microtomentose; dorsocentral setae 3 (1+2); a row of small acrostichal setae extending to scutellum, with a longer prescutellar acrostichal setae; basal scutellar setae conspicuously smaller than apical setae; posterior notopleural seta distinctly elevated above level of anterior seta; a distinct dorsoclinate seta toward anterodorsal corner of anepisternum; legs typical, usually without distinct setae, color of tarsi brown; stem of halter short, head oval, white; wing mostly hyaline, some species infuscate around crossveins and veins; costa relatively long, extended to vein M 1; costal vein sometimes bearing spines.

Abdomen: Tergites gray to brown, microtomentose; sternite 1 absent or membranous. Male Terminalia ( Figs 32, 33, 40–43 ): epandrium a closed plate around cercal cavity, sometimes with processes laterally; surstyli united but distinguishable of epandrium, or absent; gonites roughly to distinctly Y-shaped, dorsal arms flattened or sharply terminated, generally without setae; phallapodeme laterally flattened, in lateral view curved or dorsoventrally flattened, usually with 2 lateral projections, rod-like, lacking a keel; ejaculatory apodeme lacking. Aedeagus shoe-shaped in lateral view short or elongate; some species with distiphallus; distiphallus, if present, with membranous ventral elongate process that originates from distal aedeagal margin, covered by short, sharp scales or scale-like thorns. Female Terminalia: sternite 8 divided, as 2 lateral, subquadrate sclerites; female cerci without prominent setae. Female ventral receptacle without operculum only extended process present.

Distribution. Afrotropical (Cape), Australasian, Nearctic (including northern Mexico), Palearctic Regions.

Remarks. Species of this genus often proliferate best where saline or alkaline conditions are near saturation ( Mathis 1979b, Mathis et al. 2004). Immature stages are unknown. The nine species of Haloscatella are quite homogeneous in overall appearance, but structures of the male terminalia are also similar to males of other tribes of Ephydrinae , especially Ephydrini , as well as to the genera Philotelma and Scatophila within Scatellini . The species of Haloscatella that share the same states of characters with Philotelma and Scatophila are all from New Zealand. This peculiarity makes Haloscatella an important and pivotal genus in our understanding of the evolution of Scatellini .

Figures

Figures 3–9. (3)Scatella (Teichomyza) fusca, head anterior; (4) Scatella (Synsoplos) sturdeeanus, head lateral; (5)Lamproscatella cephalotes, head dorsal; (6–8) Scatella (Scatella) stagnalis, thorax lateral; (7) thorax dorsal; (8) female, abdomen lateral; (9) Haloscatella arichaeta, thorax dorsal. Abbreviations: anepst, anepisternum; ar, arista; d ped s, dorsal pedicel seta; dc s, dorsocentral seta; fr-orb s, fronto-orbital seta; fr vit, frontal vitta; gn s, genal seta; ial s, intra-alar seta; kepst, katepisternum; npl s, notopleural seta; p spal s, posterior supra-alar seta; pprn lb, postpronotal lobe; prepst, proepisternum; presut acr s, presutural acrostichal seta;presut spal s, presutural supra-alar seta;sctl, scutellum; spal s,supra-alar seta;sctl s,scutellar seta.

Figures 24–47.Abdominal sternites and terminalia: (24)Philotelma sp.,female; (25)Philotelma sp.,male;(26)Ephydra (Ephydra) riparia, female; (27) Scatella (Scatella) stagnalis, female; (28) Scatella (Scatella) tenuicosta, female; 29, Scatella (Scatella) tenuicosta, male; (30) Scatella (Scatella) paludum, male; (31) Lamproscatella sibilans, epandrium and cerci, posterior; (32) Haloscatella arichaeta, epandrium andcerci,posterior;(33)Haloscatella karekare,epandrium and cerci,posterior;(34)Hyadina sp., aedeagus lateral;(35)Parydra aquila, aedeaguslateral;(36)Thinoscatella lattini, internal structures ofmaleterminalia (aedeagus[shaded], phallapodeme, gonite+hypandrium), lateral; (37) Diedrops steineri, aedeagus, lateral; (38)Lamproscatella sibilans, internal structures of maleterminalia (aedeagus [shaded],phallapodeme,gonite+hypandrium),ventral;(39)Lamproscatella sibilans, internal structuresof maleterminalia(aedeagus[shaded],phallapodeme,gonite+hypandrium), lateral;(40)Haloscatella arichaeta epandrium and cerci, lateral; (41) Haloscatella arichaeta, internal structures of male terminalia (aedeagus [shaded], phallapodeme, gonite+hypandrium),lateral;(42)Haloscatellakarekare,internal structures of maleterminalia (aedeagus[shaded],phallapodeme, gonite+hypandrium), ventral; (43) Haloscatella karekare, internal structures of male terminalia (aedeagus [shaded], phallapodeme, gonite+hypandrium), lateral; (44) Paracoenia bisetulosa, ventral receptacle lateral; (45) Notiocoenia paniculate, ventral receptacle lateral; (46)Scatella (Scatella) stagnalis, ventral receptacle lateral; (47)Philotelma defectum, ventral receptacle lateral.