Leptomorphus quadrimaculatus (Matsumura)

Borkent, Christopher J. & Wheeler, Terry A., 2012, Systematics and Phylogeny of Leptomorphus Curtis (Diptera: Mycetophilidae) 3549, Zootaxa 3549, pp. 1-117 : 57-58

28. Leptomorphus quadrimaculatus (Matsumura)

( Figures 33, 70, 116, 141, 150, 154)

Boletina 4-maculata Matsumura, 1916: 440.

Coelosia (Boletina) 4-maculata: Matsumura, 1931: 404.

Lepitomorphus 4-maculata: Okada, 1936: 99 (lapsus).

Lepitomorphus 4-maculatus: Okada, 1939: 302.

Leptomorphus (Leptomorphus) quadrimaculatus: Matile, 1977: 144 .

References: Okada 1938: 93 ( Japan: Hokkaido, South Kuril Islands); Matile 1977: 144 (subgeneric placement); Zaitzev 1984 (details and figure of the digestive tract), 1994: 157, 160 (key, re-description, male genitalia figure), 1999: 170–171 (key, male genitalia figure); Krivosheina et al. 1986: 134, 137 (key, genitalia figure [given as L. forcipatus though genitalia = L. quadrimaculatus ); Matile, 1988: 234 (catalogue); Krivosheina & Zaitzev 2008: 608 (larval habitat).

DIAGNOSIS: Other than L. subforcipatus this is the only extant species of Leptomorphus with both the gonocoxite longer than, and placed apically on, tergite 9, and a triangular, basal, medial-projecting process ( Fig. 116). This species is darker in colour on the thorax than L. subforcipatus and does not have a slightly bulbous tip to the gonocoxite. See discussion under L. subforcipatus for more information. This species can be distinguished from the other Palaearctic species by the dark brown or black body with yellow legs ( Fig. 33) and scutum evenly covered with small setae.

DESCRIPTION: Male. ( Fig. 33) Head: brown to dark brown, somewhat dorsoventrally compressed in anterior view. Antenna dark brown; scape brown with some yellow spots, with dark brown setae in single apical row extending from dorsum laterally into thick patch covering apicoventral process, basal third and entire medial surface bare, anterobasal patch of setulae present; pedicel light brown/yellow, with 3–4 large bristles, several setae on apicodorsal margin, a few of fine setae on apicoventral margin; flagellomere 1 with tapered base light brown remainder brown; flagellomere 6 1.8X as long as broad. Clypeus brown, strongly protruding, slightly laterally compressed oval; bristles on clypeus brown, both strong, smaller bristles on entire surface, all directed ventrally, clypeus 2X as long as face. Face brown; shape a subequal triangle, with fine bristles covering face. Frons from brown to dark brown; with few bristles medioventrally, frontal furrow running 3/4-full distance from dorsal margin towards ventral margin, frontal cleft just anterior of median ocellus. Palpus yellow; segment 1 hidden behind eye, segments increasing in length, segment 5 subequal in length to segment 4 with even width from base to apex, segment 3 without distinct apicolateral patch of fine setae. Labellum brown. Eye with a number (in ~1/4 of the ommatidial junctions) of long inter-ommatidial setulae scattered on all but medial margin. Occiput brown with appressed, anteriorly directed setae. Ocelli with median slightly in front of laterals, space between ocelli less than diameter of laterals, lateral ocelli 1.5X their own diameter from eye margin, ocellar triangle dark brown/black. Thorax: Length 1.94 ± 0.41 mm (1.64 – 2.13 mm, n = 5). Dark brown. Scutum dark brown/black with blue-green specks; surface of scutum covered with small setae; acrostichal setae absent; dorsocentral setae probably present but not clearly distinguishable from other setae; multiple rows of lateral setae present; patch of setae on scutum at wing base present. Scutellum dark brown; with 8–10 large bristles and many small bristles. Prescutum brown. Mediotergite dark brown with 16–20 bristles on posterolateral corners, anteromedial patch of small bristles. Laterotergite brown; anterior margin of laterotergite not reaching katepisternum. Anepimeron brown. Anepisternum brown. Katepisternum brown. Antepronotum and proepisternum brown. Margin of anterior and posterior spiracles yellow with brown trichia. Metepisternum dark brown. Anapleural suture straight and clear. Halter stem yellow, knob light to dark brown. Legs: principally yellow; coxa with basal margin dark brown; trochanters sometime light brown; extreme anteroapical corner dark brown on all femora; tarsi changing from yellow to brown from tarsi I to V. Midfemur without apical spine-like process. Tibia with covering of yellow macrotrichia, foretibia with comb of short setae along length of anteroventral surface, foretibial spur yellow, remainder brown, foretibial spur length 2X apical thickness of foretibia, midtibia with strong, dorsal, bare patch of even thickness for 2/3 of its length, placed basally, shortest midtibial spur 0.75X length of longest, longest midtibial spur 3.75X apical thickness of midtibia, shortest hind tibial spur subequal to length of longest, longest hind tibial spur 3X apical thickness of hind tibia. Foreleg first tarsomere 1.7X length of foretibia. Wing ( Fig. 70): Length 7.9 mm (6.9–8.8 mm, n = 4). Hyaline; apical macula dark, reaching wing tip though fainter towards tip, extending faintly along posterior wing margin into apex of cell cua 1, cup, a 1, not joining with medial macula; medial macula extending from Sc to stem of M 1+2. Macrotrichia in all cells. Setae on basal posterior margin of wing (along base of cell a) all the same length. Calypter bare. Vein sc-r present, apical end joining R within its own length prior to origin of Rs. R 4 absent. R 5 straight, slight posterior turn near tip. M 1 reaching apex at same level as R 5, apices of M veins clearly reaching wing margin. M 4 -CuA fork arising before origin of r-m. A 2 faintly present as crease. Abdomen: Tergites dark brown. Tergite 8 smaller than all other abdominal sclerites, with 3 bristles on each apicolateral corner. Genitalia ( Fig. 116): brown. Sternite 9 sclerotized medially as rounded square, 1/4 the width of T9, membranous margins reaching gonocoxal margin. Tergite 9 a slightly wider than long oval. Gonocoxite placed centrally on T9, much longer than length of T9, medial margin not reaching median line, bearing gonostylus basally. Gonostylus a single lobe tapering to a point apically, slightly curved and with several setae, gonocoxite III associated with dorsal margin of gonostylus but not fused to it. Aedeagus 2/3 length of T9, tapering towards apex for basal 3/4 and then strongly indented and remainder squarish, apodemes ~1/2 total length. Parameres consisting of two lobes, lateral lobe a broad based spine curving laterally, medial lobe 2X length of lateral and veryu thin, apodemes 1/4 length of parameres, strongly united with gonocoxal apodemes and with a dorsal pointing small hook.

Female. As for male, except as follows. Thorax: Length 1.85 ± 0.37 mm (1.68–2.17 mm, n = 6). Wing: Length 7.4 ± 1.1 mm (6.7–8.1 mm, n = 6). Legs: Foretibia without comb of short setae on anteroventral surface. Abdomen: Cercus yellow.

Immatures. Undescribed.

BIOLOGY: Larvae have been recorded consuming spores on the underside of Stereum sp. fungi ( Krivosheina & Zaitzev 2008).

DISTRIBUTION: Far Eastern Russia and Japan ( Fig. 141) 30–1050 masl. Records from Western Europe are probably L. forcipatus , which was previously synonymized with L. quadrimaculatus .

DISCUSSION: As discussed below in the phylogeny section, the placement of Leptomorphus species in subgenera ( Matile 1977) is not supported by our phylogenetic results. This species is therefore removed from the subgenus Leptomorphus and placed solely in the genus Leptomorphus . See also discussion under L. subforcipatus .

MATERIAL EXAMINED: Holotype: adult female, pinned, labelled “[illegible handwriting over top of printed label] Sapporo/ Matsum; Boletina/ 4-maculata; [red label] Type/ Matsumura; [folded large label] Boletina/ 4-maculata/ Mats/ [line of Japanese text]; Lepitomorphus/ 4-maculatus/ (Matsumura)/ det. I. Okada; HOLOTYPE ♀ / Leptomorphus / quadrimaculatus (Mats.) / Det. C.J. Borkent, 2012” [ EIHU].

Other material: JAPAN, Hokkaido, Tokachi, Ashoromura , 5.viii.1949, R . Matsuda. (1♂, OMNH); Honshu, Kyoto, Ashiu, 7.vi.1964, M. Sasakawa. (1♀, OMNH); Yamanashi Pref., Hirogawara , Ashiyasu , 19.vii.1997, R . Matsumoto. (1♂, OMNH); 20.vii.1997, R . Matsumoto. (1♂, OMNH); 13.vii.1996, T . Saigusa. (1♂, OMNH); Kitazawa, Senjodake , 25.vii.1961, T . Saigusa. (1♀, LEM) ; RUSSIA, Far East, Primorskiy, Lazo, 11.vii.1979, A. Zaitzev. (1♂, 2♀, CNC); Lazo , Sokolchi , 12.viii.1979, A. Zaitzev. (1♀, BMNH) .