Gymnoclasiopa matanuska Mathis & Zatwarnicki

Mathis, Wayne N. & Zatwarnicki, Tadeusz, 2012, A revision of the New World species of Gymnoclasiopa Hendel (Diptera, Ephydridae), ZooKeys 248, pp. 1-69 : 28-31

Gymnoclasiopa matanuska Mathis & Zatwarnicki sp. n. Figs 35-40

Diagnosis.

This species is distinguished from congeners by the following combination of characters: Moderately small to medium-sized shore flies, body length 2.05-3.20 mm; dorsum generally microtomentose gray, microtomentum on abdomen sparser and finer. Head (Figs 35-36): Frons densely microtomentose, gray to blackish gray. Antenna black; basal flagellomere covered with silvery gray microtomentum; arista bearing 5 dorsal rays. Face somewhat flat, although antennal grooves, especially ventral margins, conspicuous; facial microtomentum distinctive, generally silvery white colored; gena relatively high, genal height greater than height of basal flagellomere; gena-to-eye ratio 0.28-0.33; gena silvery white, concolorous with face. Maxillary palpus black. Thorax: Thorax and abdomen generally densely microtomentose, gray to tannish gray, dull. Wing hyaline; costal vein ratio 0.38-0.52; M vein ratio 0.50-0.67; halter stem tan to yellowish tan; knob yellow to whitish yellow. Coxae, femora and tibia concolorous densely microtomentose gray to blackish dorsally, ventrally with some reddish coloration; fore- and hind tarsi mostly black; midtarsus with tarsomeres 1 and 2 somewhat yellowish to reddish, especially ventrally, apical tarsomeres black. Abdomen: Tergites largely gray, moderately densely microtomentose although less so than on mesonotum. Male terminalia (Figs 37-39): Epandrium in posterior view (Fig. 37) as a broadly rounded, inverted U, width of dorsal portion slightly narrower than lateral arms, lateral arms shallowly arched, gradually enlarged ventrally; cercus in posterior view (Fig. 37) unevenly semilunate, much narrower dorsally, pointed, ventral margin broadly rounded; aedeagus in lateral view (Fig. 39) slipper-like, base shallowly emarginate, tapered gradually toward apex, apex moderately narrowly bluntly rounded, in ventral view (Fig. 39) expanded laterally from narrow base on basal ¼, thereafter to apex almost parallel sided, apical margin slightly truncate, not bilobed, with thin, wing-like, narrow projections sub-basally; phallapodeme in lateral view (Fig. 39) more or less triangular, with broadly arched basal margin, in ventral view (Fig. 38) T-shaped, apical transverse bar robust, apical margin very shallowly emarginate; ejaculatory apodeme in lateral view L-shaped, in ventral view narrowly ovate with a thin, digitiform process; postgonite in lateral view (Fig. 39) narrowly tapered on extreme base, thereafter apically almost parallel sided to tapered apical 1/3, apex moderately narrowly rounded, bearing 3-4 tiny setulae along basoposterior margin and 1 setula subapically along margin toward hypandrium; pregonite in lateral view (Fig. 39) moderately elongate, tapered, acutely narrowed toward hypandrium, expanded toward aedeagus, aedeagal end truncate; hypandrium in ventral view (Fig. 38) wide, width twice length, broadly and shallowly rounded along anterior margin with shallowly extended, relatively wide, shallow, obtusely pointed lateral projections, shallowly emarginate along entire posterior margin, in lateral view (Fig. 39) angled basally, thereafter toward anterior margin irregularly parallel sided, narrow, bar-like.

Type material.

The holotype male of Gymnoclasiopa matanuska Mathis and Zatwarnicki is labeled "USA. A[las]K[a]. Mat[anuska]-Su[sitna]: Palmer (Matanuska River; 61°36.5'N, 149°04.1'W), 5 Aug 2002,D.&W.N.Mathis/USNM ENT 00183434 [plastic bar code label]/HOLOTYPE ♂ Gymnoclasiopa matanuska Mathis & Zatwarnicki, USNM [red]." The holotype is double mounted (minuten pin in a block of plastic), is in excellent condition, and is deposited in the USNM. Twenty-four paratypes (11♂, 13♀; USNM) bear the same label data as the holotype; 2 paratypes (1♂, 1♀; USNM) have the same locality data but with the date of 16 Aug 2012. Other paratypes are as follows: UNITED STATES. ALASKA. Kenai Peninsula: Kenai Fjord National Park, Exit Glacier (60°11.3'N, 149°37.6'W), D. and W. N. Mathis (1♀; USNM); Seward (21 km N; 60°17.2'N, 149°20.5'W; Snow River), 31 Jul 2002, D. and W. N. Mathis (4♂, 1♀; USNM); Swanson River Road (60°42.8'N, 150°48.9'W), 13 Aug 2012, D. and W. N. Mathis (1♂; USNM). Matanuska-Susitna: Knik River (61°27.8'N, 148°51.6'W), 5 Aug 2002, D. and W. N. Mathis (2♀; USNM); Lucile Lake (61°34.2'N, 149°28.6'W; 100 m), 15 Aug 2012, D. and W. N. Mathis (1♀; USNM); Palmer (Knik River; 61°31.2'N, 148°59.4'W), 6 Aug 2002, D. and W. N. Mathis (7♂, 1♀; USNM); Talkeetna (west, adjacent to Susitna River; 62°19.4'N, 150°07.2'W), 4-10 Aug 2003, 2011, D. and W. N. Mathis (2♀; USNM); Willow Creek (61°46.1'N, 150°04.2'W; 50 m), 10 Jul 2006, D. and W. N. Mathis (2♂; USNM). Valdez-Cordova (Census Area): Chitina (61°30.9'N, 144°26.2'W), 18 Jun 1953, W. C. Frohne (3♀; USNM); Gulkana River (19.3 km N Glennallen; 62°16.1'N, 145°23.1'W), 9 Jul-7 Aug 2006, 2011, 2012, D. and W. N. Mathis (11♂, 12♀; USNM); Klutina River (mile 101; 61°57.2'N, 145°19.3'W; 315 m), 7 Aug 2012, D. and W. N. Mathis (15♂, 4♀; USNM); Lower Tonsina Valley (61°39.3'N, 144°39.5'W), 19 Aug 1953 (1♀; WSU); Valdez (4.8 km N; 61°05.8'N, 146°14.6'W), 8 Jul 2006, D. and W. N. Mathis (13♂, 6♀; USNM).

Type locality.

United States. Alaska. Matanuska-Susitna: Palmer (Matanuska River; 61°36.5'N, 149°04.1'W).

Other specimens examined.

Palearctic. MONGOLIA. Bayan Ölgiy: Bulgan Gol (47°05.3'N, 91°01.6'E; 2055 m), 7 Jul 2009, W. N. Mathis (1♂; USNM); Bulgan Gol (15 km N Bulgan; 47°02.4'N, 91°02.1'E; 2015 m), 9 Jul 2009, W. N. Mathis (3♂; USNM); Bulgan Gol (28 km N Bulgan; 47°06.9'N, 90°56.5'E; 2122 m), 8 Jul 2009, W. N. Mathis (1♀; USNM); Burgedtein Gol (47°31.9'N, 91°16.9'E; 2520 m), 4 Jul 2009, W. N. Mathis (1♂; USNM); Chigertei Gol (7 km W Dalum; 47 °50.7'N, 90°38.6'E; 2165 m), 5 Jul 2009, W. N. Mathis (1♂; USNM); Gantsmodi Gol (27 km S Deluun; 47°37.5'N, 90°40.3'E; 2200 m), 5 Jul 2009, W. N. Mathis (8♂, 7♀; USNM); Ulaagchimy Davaa Gol (40 km N Bulgan; 47°20.9'N, 90°57.7'E; 2515 m), 6 Jul 2009, W. N. Mathis (1♀; USNM). Khovd: Bodovich Gol (8 km E Ikh Ulaan Davaa; 46°37.1'N, 92°13.8'E; 2545 m), 14 Jul 2009, W. N. Mathis (10♂, 3♀; USNM); Khovd, Buyant gol (47°58.5'N, 91°35.7'E; 1425 m), 2 Jul 2009, W. N. Mathis (1♂; USNM); Monkhkhayrkhan (47°03.3'N, 91°50.9'E; 2090 m), 16 Jul 2009, W. N. Mathis (2♂; USNM); Nevt Rashaa (9 km E Duut; 47°31.9'N, 91°42.3'E; 2050 m), 19 Jul 2009, W. N. Mathis (3♂, 1♀; USNM).

Distribution

(Fig. 40). Nearctic: United States (Alaska). Palearctic: Mongolia (Bayan Ölgiy, Khovd).

Etymology.

The species epithet, matanuska, refers to the glacier, river, and valley in southcentral Alaska where many specimens of the type series were collected along lotic aquatic systems. The name is apparently of Athabaskan origin and means a strong, gusty, northeast wind, which occasionally occurs in this region during the winter. The name is a noun in apposition.

Remarks.

Like a number of shore-fly species with Holarctic distributions, including Gymnoclasiopa matanuska , the Bering Strait is apparently a conduit between the Old and New Worlds.

Although similar to other congeners, especially Gymnoclasiopa grecorum , this species is distinguished by the black maxillary palpus and basitarsomere of the foreleg, the densely microtomentose gray to tannish gray body, especially on the thorax and abdomen, and the high genal height.