Megophthalmidia browni, Kerr, Peter H., 2014

Kerr, Peter H., 2014, The Megophthalmidia (Diptera, Mycetophilidae) of North America including eight new species, ZooKeys 386, pp. 29-83 : 31-34

Megophthalmidia browni sp. n. Figs 1-10

Type material.

Holotype: ♂, "USA: CA: Santa Barbara Co., UC Sedgwick Reserve, Malaise, 34.6853°N,-120.0461°W, 1-5.ii.2005 M. Caterino CSCA12L353" / "HOLOTYPE 12K450, Megophthalmidia browni ♂, Kerr, 2014" [red label]. Deposited in CSCA, mounted on gray point, complete specimen in good condition (Fig. 1).

Paratypes (all bearing a blue paratype label): ♂, "USA: CA: Los Angeles Co., Brentwood 34.07°N, 118.49°W, 2-20.iii.2008 M. Schulman, MT, backyard garden CSCA08L642" [CSCA; locality Fig. 105, specimen # 12J952 (dissected, Figs 2-10)]; ♂, "USA: CA: Los Angeles Co., Brentwood 34.07°N, 118.49°W, 20. iii– 9.iv.2008 M. Schulman, MT, backyard garden CSCA08L640" [CSCA; specimen # 09E060].

Additional material examined: 3 ♂♂, "MEX. Baja Calif. Norte, Arr. Santo Domingo, 5.7mi E. Hamilton Ranch / dam site, 18 –IV– 1963, H.B. Leech, P.H. Arnaud, Jr." [CAS; one specimen dissected, specimen # 13M591].

Diagnosis.

Megophthalmidia browni sp. n. is most similar to Megophthalmidia lenimenta sp. n. having epandria that have a medial furrow and central notch, with slender apical processes. In Megophthalmidia browni , the apical epandrial processes are longer (Fig. 2) than in Megophthalmidia lenimenta (Fig. 22), but differences between the species are more obvious in the aedeagal morphology. Megophthalmidia browni bears a recurved aedeagal fork (Fig. 8) whereas in Megophthalmidia lenimenta , this structure is lacking (Fig. 28). Megophthalmidia browni may be distinguished from Megophthalmidia ignea and Megophthalmidia perignea by the shape of the apical epandrial processes (narrow elongate, as opposed to shortened) and from Megophthalmidia mckibbeni by the distinctive invagination of the apical epandrial processes at their base and the presence of a dorsally-reflexed bifurcation of the aedeagal fork (absent in Megophthalmidia mckibbeni ). The aedeagal complex of Megophthalmidia browni displays bifurcating tines of approximately the same width, in which the shorter fork is directed anteriorly (Fig. 8).

Description.

Male. Body length: 2.7-2.8, 2.1 [2.7] mm (n=2). Wing length: 2.6-2.8, 2.7 [2.8] mm (n=3).

Coloration (Fig. 1). Head dark brown; antennal scape dark brown, pedicel brown or bearing some cream-color or pale yellow, and flagellomeres brown; face dark brown, clypeus and labrum brown to dark brown; palps and labellum cream-colored to pale yellow (palpomeres 1 and 2 usually slightly darker than others, palpomere 2 with light patch where sensilla present). Thorax brown to dark brown throughout, except at the anterolateral margin of the dorsum and dorsal pronotal area, where it is cream-colored or pale yellow; scutum setae golden brown to dark brown. Coxae clearly lighter in color than thorax, cream-colored to pale yellow; femora cream-colored to light brown throughout (except sometimes slightly brown at dorsal apex); tibiae and tarsi cream-colored to pale yellow, with densely-arranged dark brown setae; hind tibial comb yellowish, preceded by 0-3 (usually 3) dark brown setae. Wing hyaline without markings, wing veins brown; haltere stem and knob white to cream-colored. Abdominal segments light brown to brown, darker laterally. Terminalia light brown to brown.

Head. Ocelli slightly raised, median ocellus in line with anterior margin of lateral ocelli, median ocellus approx. 0.5 × size of lateral ocelli; lateral ocellus located approx. 2 × diameter of ocellus from eye margin, separated from median ocellus by approx. 2.3 –2.8× its own diameter. Eyes with microsetae, which are approximately as long as width of facet. Frons microtrichose, without setae, flattened. Antennal length 1.4-1.6, 1.5 [1.6] mm (n=3). Face clearly longer than wide, setose; clypeus and labrum microtrichose, without setae. Palpus with four palpomeres; palpomere 1 oblong, without setae; other palpomeres with brown setae; palpomere 2 bearing small pocket of sensilla; palpomere 1 length longer than or subequal in length to palpomere 2; palpomere 3 length shorter than combined length of palpomeres 1 and 2; palpomere 4 subequal in length to combined length of palpomeres 2 and 3.

Thorax. Dorsum with evenly-distributed, short, appressed setae, bearing longer setae only along lateral and posterior margins. Antepronotum, proepisternum, and laterotergite bearing setae; remaining lateral thoracic sclerites bare. Costal wing vein extends beyond R5, approx. two-thirds distance between R5 and M1; R1 approximately the same length as r-m or slightly longer; cubital fork proximad of r-m base (as in Megophthalmidia occidentalis , Fig. 52); R1, M1, M2, CuA1, and CuA2 with setae on upper surface (lacking setae on M1 + M2). Wing veins A1 and CuP absent.

Male genitalia (Figs 2-10). Epandrium dorsal surface with clear medial depression, where setae are lacking; posterior margin narrowly emarginate at center (Fig. 4). Posterior processes of epandrium elongate, approx. 5 –6× longer than wide, separated at base by approx. 1 × width of process, length of setae at base of epandrial processes 2 –3× width of process, bare along most of length (Figs 2, 3). Gonocoxites as in Figs 5-7. Aedeagal fork bifurcated into elongated tines of similar width; shorter tine recurved to point anteriorly, longer tine curved outward (Figs 8-10).

Female unknown.

Etymology.

The species epithet “browni” is a noun in the genitive case, named in honor of Brian V. Brown, friend, colleague, mentor, and Curator, Natural History Museum of Los Angeles County.