Drymeia firthiana (Huckett, 1965)

Sorokina, Vera S. & Ovtshinnikova, Olga G., 2020, The position of the Azeliinae in the Muscidae (Diptera) based on musculature of the male terminalia, ZooKeys 975, pp. 87-110 : 87

publication ID

https://dx.doi.org/10.3897/zookeys.975.55502

publication LSID

lsid:zoobank.org:pub:68B311A1-4AA5-408F-9509-0A52245290AA

persistent identifier

https://treatment.plazi.org/id/1FCD2321-A12A-5327-ACF1-9253F92FEF69

treatment provided by

ZooKeys by Pensoft

scientific name

Drymeia firthiana (Huckett, 1965)
status

 

Drymeia firthiana (Huckett, 1965) Figures 1 View Figure 1 , 2 View Figure 2 , 3 View Figure 3 , 4 View Figure 4 , 9 View Figure 9

Material examined.

10 males, Russia, Altai Republic, Kosh-Agach district, 8 km NE Maitobe Mt., 2420 m, 49°34'N, 87°43'E, pan traps, 7-10.vii.2006, leg. V. Sorokina.

Description.

Abdominal segments. Sternite I reduced to narrow band, tergites I and II fused. Segments III and IV and tergite V not modified; sternite V enlarged, with wide median notch.

Pregenital segments (Fig. 1 View Figure 1 ). Tergite VI reduced to long narrow sclerotized band. Sternite VI positioned under sternite V, reduced in size, represented by short, narrow, wavy sclerite; remainder of sternite VI desclerotized. Sternite VII long, narrow, positioned on left side of body, dilated at articulation with syntergosternite VII + VIII; ventrally connected to desclerotized left margins of sternite VI; laterally connected to syntergosternite VII + VIII. Syntergosternite relatively wide, positioned dorsally; left end wider than right end and connected to sternite VII, right end free; posterior margin extended to epandrium.

Genitalia. Hypandrium in form of concave plate, V-shaped (Fig. 2A View Figure 2 ); lateral arms of hypandrium articulated with surstyli and epandrium. Pregonites and postgonites present; pregonites larger than postgonites, tapered apically, and longer phallapodeme (Figs 2B View Figure 2 , 9B View Figure 9 ). Phallus comprises epiphallus and distiphallus, basiphallus inconspicuous, either absent or fused with distiphallus. Phallapodeme long, articulated with phallus. Epiphallus well-developed, shaped as long and distally rounded plate. Distiphallus large, as long as pregonite, expanded distally, broadly articulated with epiphallus. Ejaculatory apodeme concave-shaped plate. Epandrium hemispherical, with large posteromedian notch (Fig. 3 View Figure 3 ). Cerci large, wide, fused for a considerable length; each cercus with distal semicircular apical notch and well-formed process (Fig. 3B View Figure 3 ). Surstylus well-developed, wide, expanded and rounded apically, bent inward, with small process. Cercus approximately as long as surstylus. Subepandrial sclerite present as two long, quite wide, medially not connected plates, as long as length of surstyli and merging with them (Figs 4 View Figure 4 , 9F View Figure 9 ).

Thoracic muscles . Paired symmetrical conical muscles extend from thorax to lateromedian parts of tergite I + II, and also straight muscles extend from thorax to basal parts of sternite II.

Abdominal muscles (Fig. 1 View Figure 1 ): ITM 2-ITM 4, ITM 5a, ITM 5b, ISM 2-ISM 5, TSM 1-TSM 5. Flat, very short muscles ITM 2-ITM 4 extend from distal parts of tergites II-IV along their entire width to basal margins of tergites III-V. Paired symmetrical muscles ITM 5a extend from median parts of tergite V to median parts of basal margin of tergite VI. Long, paired, almost symmetrical conical muscles ITM 5b extend from laterobasal parts of tergite V to membrane at lateral parts of tergite VI.

Paired symmetrical muscles ISM 2-ISM 4 extend along the entire basal margin of sternites II-IV to basal margins of sternites III-V, respectively. Very powerful, paired, symmetrical, fan-shaped muscles ISM 5 extend in two layers from basal margin of sternite V to sclerotized plate of sternite VI and to sternite VII at connection with membrane of sternite VI. Muscles extending to sternite VI connected with middle part of sternite V, but muscles extending to sternite VII connected with basal part of sternite V. Wide and flat pleural abdominal muscles TSM 1-TSM 5 easily discernible on corresponding segments.

Pregenital muscles (Figs 1 View Figure 1 , 2A View Figure 2 , 3A View Figure 3 , 4 View Figure 4 ): ITM 6, ISM 6, ISM 7, TSM 7, M 18, M 191, M 192. Small and short, paired, slightly asymmetrical muscles ITM 6 extend from lateral parts of tergite VI to lateral parts of syntergosternite VII + VIII.

Paired muscles ISM 6: left ISM 6 extends from left membranous parts of sternite VI to lateral margin of inner surface of sternite VII, articulated with syntergosternite VII + VIII; right muscle ISM 6 extends from right membranous parts of sternite VI to membrane near right laterobasal margin of syntergosternite VII + VIII; left ISM 6 larger than right muscle ISM 6. Unpaired left muscle ISM 7 short but powerful, extending from lateral margin of outer surface of sternite VII to outgrowth on lateral part of basal margin of syntergosternite VII + VIII. Paired asymmetrical muscles TSM 7: left muscle TSM 7 wide, short, fan-shaped, extending from lateral part of inner surface of sternite VII to small outgrowth on lateral margin of syntergosternite VII + VIII; right muscle TSM 7 long, fan-shaped, extending from right basal margin of sternite VII to small, sclerotized part of membrane adjacent to syntergosternite VII + VIII.

Paired asymmetrical muscles M 18: right muscle M 18 r wide and flat (homologous with left M 18 in Mydaeinae ), extending from membrane covering genital cavity near syntergosternite VII + VIII to middle of basal margin of hypandrium (Figs 2A View Figure 2 , 3A View Figure 3 , 9C View Figure 9 ); left muscle M 18 l long (homologous with right M 18 in Mydaeinae ), extending from left part of syntergosternite VII + VIII to inner surface of left laterobasal part of hypandrium. Paired asymmetrical muscles M 191 (Fig. 4 View Figure 4 ): left muscle M 191 l short but powerful, extending from inner surface of small area on left lateral part of syntergosternite VII + VIII (close to connection with sternite VII) to small area on left laterobasal margin of epandrium; right muscle M 191 r longer but weaker than M 191 l, extending from right part of syntergosternite VII + VIII to right laterobasal margin of epandrium. Unpaired asymmetrical muscle M 192 powerful, fan-shaped, and oblique, extending from right lateral part of syntergosternite VII + VIII to slightly to right from middle of basal margin of epandrium.

Genital muscles . Tergosternal muscles (Figs 3A View Figure 3 , 9C View Figure 9 ): M 5. Paired, symmetrical powerful muscles M 5 extend from lateral parts of basal margin of hypandrium to median parts of basal margin of epandrium.

Muscles of hypandrial complex (Figs 2 View Figure 2 , 9A View Figure 9 ): M 1, M 21, M 22, M 23, M 23. Wide and powerful, paired, symmetrical muscles M 1 extend from hypandrium, occupying considerable part of inner surface, to curve of mediobasal part of phallapodeme in front of pregonites. Long paired symmetrical muscles M 21 extend from arms of hypandrium to laterodistal parts of phallapodeme. Powerful paired symmetrical muscles M 22 extend from entire laterobasal part of pregonites to distal half of phallapodeme. Symmetrical muscles M 23 long and close to each other, extending from membrane of basal margin of epiphallus between lateral ends of hypandrial arms to distal part of phallapodeme, opposite epandrium; muscles M 23 very close to muscles M 21 and both look like one muscle. Constrictors of ejaculatory apodeme small; muscles M 23 surrounding ejaculatory apodeme, contraction pumps seminal fluid into phallus.

Muscles of epandrial complex (Figs 3B View Figure 3 , 4 View Figure 4 , 9E View Figure 9 ): M 3, M 4, M 7, M 24-M 26. Powerful paired symmetrical muscles M 3 extend from inner surface of basal parts of epandrium to inner surface of basal parts of subepandrial sclerite. Powerful paired symmetrical muscles M 4 extend from lateral parts of inner surface of epandrium to inner surface of basal parts of surstyli. Paired symmetrical thin cercal muscles M 7 extend from inner part of subepandrial sclerite to laterobasal parts of cerci. Broad powerful muscle M 24 passes inside cerci connecting lateral parts of two halves of cerci. Broad paired muscles M 25 extend from median parts of distal margin of epandrium to integument of anus. Powerful paired symmetrical, fan-shaped muscles M 26 extend from distolateral parts of epandrium to laterobasal margins of small cercal outgrowths.

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Diptera

Family

Muscidae

Genus

Drymeia