Megaselia arbuciensis García-Romera, 2014

García-Romera, Carlos & Barrientos, Jose Antonio, 2014, Nine new species of Phoridae (Insecta: Diptera) from Spain, Zootaxa 3857 (2), pp. 244-260 : 245-246

Megaselia arbuciensis García-Romera sp.nov.

( Figs 1–2 )

Etymology. The species is named after its type locality.

Diagnosis. Longest bristle on palp clearly longer than maximum width of palp; mesopleuron bare; scutellum with a posterior pair of bristles and an anterior pair of hairs; notopleuron with three bristles; abdominal venter with hairs on segments 3–6, with those on sixth segment weak; left side of epandrium with hairs which are more robust than hairs of cerci; posterior left lobe of hypandrium developed; anal tube shorter than length of dorsal face of epandrium; bristles at rear margin of sixth abdominal tergite subequal to most robust hairs on left side of epandrium; all femora brown; fore tarsus uniformly brown, with fifth segment being a little narrower than fourth one; longest hairs below basal half of hind femur about as long as those of anteroventral row of outer third; knob of haltere brown; with five axillary bristles; costal index less than 0.44; costal cilia (section 3) about as long as longest axillary bristle.

Description (male). Head. Frons brown, about as broad as long, with 113 hairs. Upper supra-antennal bristles about as long and strong as lower pair, and they are about as closer together as pre-ocellars, which are slightly lower on frons than mediolaterals and clearly closer together than either is from a mediolateral bristle. Upper supraantennal bristles at about the same level on frons as antials, which are lower on frons than anterolaterales, and about as far apart from these as from upper supra-antennal bristles. Gena with three long bristles and five shorter ones. Antennal postpedicel subglobose, brown and relatively small (diameter 0.10 mm), with SPS vesicles, each about diameter of basal socket of antial bristles. Palps dusky yellow, 0.10–0.17 mm long and 0.05 mm maximum width, with five bristles, the longest bristle being longer than greatest width of palp. Labella enlarged, yellow, with only a few short spinules below and a few long hairs. Labrum brown, about 0.85 × as wide as an antennal postpedicel.

Thorax. Brown. Mesopleuron bare. Three notopleural bristles and no cleft in front of these. Scutellum with an anterior pair of small hairs and a posterior pair of bristles. Propleura with 3–4 hairs on posterodorsal edge, 3–4 on posteroventral one and a few in middle, situated well forward of hindmargin.

Abdomen. Tergites light brown, with scattered short hairs with those of the rear margin of T6 only a little longer than the rest and about as long and strong as those on epandrium. Venter grey, with a few short hairs on segments 3–6.

Hypopygium ( Figs 1–2 ). Left side of epandrium light brown, without bristles, with hairs stronger than those on cerci, which are weaker than those on proctiger. Anal tube yellow, a little shorter than dorsal face of epandrium. Hypandrium, light brown, with both posterior lobes developed and with minute hairs below.

Legs. Light brown, slightly clearing from the posterior to anterior legs, but without being yellowish. Front legs with a posterodorsal hair palisade on tarsal segments 1–4 and metatarsus a little enlarged. Length ratios of the fore tarsal segments 2.3:1.3:1.2:0.9–1:1, with fifth segment narrower than fourth one. Mid legs with a dorsal hair palisade on tibia extends about 2/3 of its length. Longest hairs below basal half of hind femur about as long as those of anteroventral row of outer third. Hind tibia with 15–18 differentiated posterodorsal hairs and spinules of apical combs simple.

Wing. Length 1.70–1.76 mm. Membrane lightly tinged grey and veins light brown; with five axillary bristles. Subcosta (Sc) not reaching R1. One hair present at base of vein Rs, 0.025–0.040 mm long. Costal index 0.35–0.40; costal ratios 3.5–3.8:1–1.2:1. Costal cilia (section 3) 0.12–0.13 mm long, about as long as longest axillary bristle. Knob of haltere brown.

Recognition. In the keys to the males of the British species of Megaselia ( Disney, 1989) this species runs to couplet 87, after return of 182, to M. conformis (Wood) , but its hypopygium clearly differs from the new species, in the shape of epandrium and development of posterior lobe of hypandrium; the subsequently added M. lactipennis Lundbeck , runs to the same point; it differs from the new species clearly in the hypopygium (development of posterior lobes of hypandrium, shape of epandrium and thickness of hairs of epandrium and proctiger), in length of hairs of the rear margin of tergite 6, length of the hairs below basal half of hind femur and length of costal cilia (Disney, 2000). The subsequently described M. putescavi Disney runs to this couplet, but it is distinguised from the new species by having hairs on mesopleuron and a clearly different hypopygium, especially a larger left lobe of hypandrium ( Disney & Withers, 2011).

Material examined. Holotype ♂ Spain, Girona: Arbucias, Montseny Natural Park, beech forest, UTM 31TDG540279, 1250 m a.s.l., 19/ 05-02/06/1990. Window trap. J.A. Barrientos leg ( UAB).

Paratype ♂, same date, locality, habitat and capture method as holotype (CCG-R).

Figures

FIGURES 1 – 2. Megaselia arbuciensis García-Romera sp. nov. male. 1, left face of hypopygium. 2, right face of hypopygium. Scale bars = 0.1 mm.