Meoneura joedaltoni, Stuke & Barták, 2019

Stuke, Jens-Hermann & Barták, Miroslav, 2019, Records of Carnidae from the collection of Miroslav Barták (Diptera: Carnidae), with the description of five new species, Zootaxa 4567 (2), pp. 326-346 : 338-340

Meoneura joedaltoni spec. nov.

( Figs. 15–18 )

Holotype ♂: (1) „I: Amatrice-5kmS, pi- / ne wood nr.pasture / 42.39N / 13.20E 1700 m / Barták 3.viii.1988 “; (2) „ Holotypus / Meoneura joedaltoni / spec. nov. ♂ / det. Stuke 2018“.

The holotype is deposited in the collection of the Czech University of Life Sciences, Czech Republic, Prague (CULSP). The specimen is glued on a card. Otherwise the specimen is in good condition. The posterior part of abdomen is dissected, macerated and stored in a glycerine microvial pinned underneath the specimen.

Description of holotype (male). Length about 1.5 mm. Wing length 1.2 mm.

Head height 0.4 mm. Face, anterior half of frons and gena below the eye orange brown. Posterior half of frons brown with frontal triangle black. Occiput and main part of gena black. Antenna brown. Arista without pubescence. Maximum eye length: maximum eye height = 1.0. Posteroventral margin of gena closest to eye margin: maximum eye height = 0.6. Frons slightly microtomentose, slightly microtomentose. Frontal triangle distinct, reaching about 1/3 distance from anterior ocellus to frontal margin. Face microtomentose. Carina broad, almost as broad as fore tibia. Postcranium microtomentose. Prementum and palpus cannot be examined at the holotype due to the preparation. 1 distinct ocellar seta; supralunular almost parallel; 4 fronto-orbital setae (2 anterior mesoclinate, 2 posterior lateroclinate), the posterior mesoclinate seta short, only 1/3 of the length of the anterior mesoclinate seta. Perhaps this short seta is an additional anterior mesoclinate seta and another larger mesoclinate seta is broken (on both sides of the head). 2 vertical setae; 2 mesoclinate postorbital setae; postocellar setae slightly divergent; 1 strong vibrissal seta; supravibrissal setae incomplete in the holotype; 1 strong and 2 slightly smaller genal setae.

Scutum microtomentose, covered with short, semiadpressed black setulae. Scutellum microtomentose. Pleurae—as far as can be seen in the type—microtomentose. Scutum with 1 long posterior dorsocentral seta only. 2 postpronotal setae; 1 praesutural seta; 2 notopleural setae; 1 supraalar seta; 2 postalar setae; 1 praescutellar seta; 1 apical and 1 lateral scutellar seta. Setae on katepisternum and anepisternum cannot be examined in holotype. 1 dorsal seta and 1 ventral seta on katepisternum. Costa with no obvious setae beyond radial vein R 1. Wing hyaline, veins light yellow to yellow brown. R 4+5 slightly curved to apex of wing. Haltere brown, base of haltere brown. Legs black to brown. Fore femur basally with 2 and apically with 2 strong posteroventral setae. Hind femur apically with 1 strong anteroventral seta. All coxae with single inconspicuous black setae. Hind metatarsus ventrally with dense yellow golden setae. Length metatarsus 2: length tibia 2 = 0.5.

Tergites with no obvious depressions or tufts of setulae. Abdominal pleura with scattered setae on abdominal segments 3–5. Abdominal segments 1–5 narrow, width of tergite 3: length of tergite 3 = 3.1. Tergites 2–5 each with 1 distinct lateral seta at the posterior margin, and tergite 5 with 2 setae at the posterior margin. Sternite 5 wider than long; the posterior margin slightly concave ( Fig. 18 ). Sternite 5 with scattered setae in the posterior half. Midventral tergite 7 distinct. Protandrium small, shorter than epandrium and about 0.4 of length of tergite 5. In the holotype the protandrium is almost completely hidden by tergite 5. Epandrium with four outstanding lateral setae—the basal distinctly longer than the three other—and one smaller setae ( Fig. 15 ). Maximum length dorsally in the middle of epandrium: maximum width of epandrium = 0.4. Cerci indistinct, not projecting, and no setulae recognized. Subepandrial plate distinctly sclerotised. No setula recognized on subepandrial plate. No proceeding of hypoproct. No tooth on subepandrial plate. Surstylus as in Fig. 16 : large, parallel sided, anteriorly rounded. Surstylus with few setulae only. No lamella. Postgonite as in Fig. 17 : distinctly sclerotised, broad, hardly elongated, dorsoapically pointed. Distiphallus small, inconspicuous, curved, longer than epandrium and surstylus, covered with dense light brown setulae. Basiphallus obviously sclerotised, long, narrow, at its base widened.

Diagnosis. An exciting character of M. joedaltoni is the completely brown halter that is otherwise only known from European Meoneura elongella Zetterstedt, 1838 , Nearctic M. nigrifrons Malloch, 1915 and Nearctic M. wirthi Sabrosky, 1959 . While the two Nearctic species have completely different structures at the postabdomen (cf. Sabrosky 1959) the European M. elongella is only known from female specimens. The most obvious character to distinguish the holotype of M. joedaltoni and a female of M. elongella from Norway is the more yellow coloured head (face, gena at eye margin and about half of the frons) of M. joedaltoni . This character is important in other Meoneura species, for example to distinguish the closely related species of the M. flavifacies -group. It is described in Zetterstedt´s description of M. elongella . Another obvious character is the higher face between antennal groove and upper mouth opening (higher than fore tibia diameter) in M. joedaltoni .

In regard to the postabdomen, Meoneura joedaltoni belongs to the Meoneura palaestinensis -group sensu Stuke & Freidberg (2017) that is characterised by a broad and anteriorly rounded surstylus and the lack of an adjected lamella ( Fig. 16 ). M. joedaltoni is easily identified by this unique combination of characters: (1) face and anterior half of frons orange yellow; (2) carina about as broad as fore tibia; (3) scutum and scutellum distinctly microtomentose; (4) 1 dorsocentral only; (5) haltere completely brown; (6) epandrium with 1 outstanding and 3 distinct setae ( Fig. 15 ); (7) cercus indistinct and without recognized setae; (8) surstylus as in Fig. 16 : large, almost as long as epandrium, parallel sided, not narrowing basally, apically rounded, not tapering and not hyaline apically; (9) hypoproct without any proceeding; (10) sternite 5 slightly wider than long, hind margin slightly concave ( Fig. 18 ). A key of the Meoneura palaestinensis -group was published by Stuke & Freidberg (2017). M. joedaltoni will run to the last couplet 4 together with M grimmorum Stuke & Freidberg, 2017 and M. palaestinensis Hennig, 1937 , but will not be assigned to one of these species due to the very different shape of the surstylus and the combination of characters mentioned above.

Etymology. The species is named after Joe Dalton, the smallest of the four Dalton brothers, who appear in the Lucky Luke comic book series of Maurice de Bevere (Morris) and René Goscinny. Joe is the smallest of the four Dalton brothers as Meoneura joedaltoni is one of the smallest Acalyptratae.

Distribution. Meoneura joedaltoni has been caught only at the locus typicus, a pine wood 5 km south of Amatrice (Latium, Italy). The coordinates of the label don´t fit exactly to this description but are about 4 km ssw of Amatrice.

Meoneura lacteipennis ( FALLÉN, 1823)

Material: CZECH REPUBLIC: 1♂, 22.v.1995, Vráž u Písku , near pond [49.23°N 14.08°E], 400 m, leg. M. Barták, coll. CULSP ; TURKEY: 1♂, 17.–22.v.2011, Muğla, University campus, 700 m [37°09’42’’N 28°22’21’’E], 700 m, pan trap +sweeping, leg. M. Barták & Š. Kubik, coll. CULSP .

Diagnosis: Collin (1930).

Meoneura lamellata COLLIN, 1930

Material: CZECH REPUBLIC: 1♂, 30.vi.–7.vii.2015, Praha, Troja [50°07’15’’N 14°23’53’’E], 184 m, emergence trap, pig caracas, exp. 9.xii.2014, leg. M. Barták, coll. PJHS ; 1♂, 27.v.–2.vi.2015, dito, coll. CULSP ; 1♂, 22.–29.v.2012, Praha, Troja [50°07’15’’N 14°23’53’’E], 184m, emergence trap baited with pig caracas, leg. M. Barták, coll. CULSP ; 1♂, 27.vi.–3.vii.2012, dito.

Diagnosis: Collin (1930).

M. lamellata is new for the Czech Republic.

Figures

FIGURES 15–18. Meoneura joedaltoni spec. nov. (drawn from holotype). 15. Lateral view of epandrium and surstylus. 16. Lateral view of surstylus. 17. Lateral view of postgonite. 18. Ventral view of sternite 3 (left)—sternite 5 (right).