Megaselia necmera, Disney, R. Henry L., 2006

Disney, R. Henry L., 2006, Eight new species of Megaselia Rondani (Diptera: Phoridae) from the United Arab Emirates, Oman, and Yemen, Zootaxa 1371, pp. 1-21 : 11-13

Megaselia necmera sp. nov.

( Figs 14 – 20 )

In Beyer’s (1965) keys this species runs to couplet 3, lead 2 on page 56, to M. lilliput Beyer , which is only known in the female sex. Unfortunately Beyer omitted M. mera ( Collin, 1912) , which was also described from the female only, and which runs to the same point. However, its male has been described since ( Disney, 2006b) and M. mera recognised as belonging to a sibling species complex that includes M. jorgensis Disney , M. pseudomera Disney and M. vitiomera Disney. The new species evidently belongs to the same complex. The male’s proboscis most closely resembles M vitiomera , but the latter has darker postpedicels, thorax and abdominal venter. The hypopygia are similar but differ in detail. The female of M. vitiomera is not known.

Etymology

Named after its resemblance to the first described species of this complex, M. mera .

Male

Frons brown, with 88 – 112 hairs, with dense but fine microsetae and bristles arranged as in Fig. 14 . SAs unequal, the lower pair being clearly shorter. Cheek with 2 – 3 bristles and jowl with 2 longer ones. Postpedicels subglobose, pale straw yellow very lightly tinged brown and without SPS vesicles. Palps straw yellow, with 3 – 6 bristles (all shorter than lower SAs) and 4 – 7 hairs. Labrum and labella as Fig. 20 , both being straw yellow and the latter with fields of at least 50 scattered short spinules below each. Thorax yellow to brownish yellow, being paler on sides. Mesopleuron bare. Two notopleural bristles and no cleft in front of these. Scutellum with an anterior pair of hairs (subequal to those in middle of scutum) and a posterior pair of bristles. Abdominal tergites light brown but variably straw yellow along median band of T3 – T5 and much of T2, with the hairs at rear of T6 longer than rest ( Fig. 16 ). Venter pale straw yellow, and with hairs below segments 5 – 6, those on 3 – 4 being reduced to microsetae. Hypopygium brown, with whitish yellow anal tube, and as Fig. 16 . Both lobes of hypandrium vestigial. With two rectal papillae. Legs straw yellow apart from brown patch on mid coxa and gradually darkened tip of hind femur. Fore tarsus with posterodorsal hair palisade on segments 1 – 4, and 5 a little longer than 4. Dorsal hair palisade of mid tibia extends almost two thirds of length. Hairs below basal half of hind femur clearly longer than those of anteroventral row of outer half. Hind tibia with 9 – 10 differentiated posterodorsal hairs, the last being little (if any) stronger than the penultimate one. Spinules of apical combs simple. Wings 0.9 – 1.1 mm long. Costal index 0.33 – 0.37. Vein 3 is unforked. Costal ratios 1.9 – 3.1: 1. Costal cilia (of section 2) 0.04 – 0.05 mm long. Hair at base of vein 3. With two axillary bristles, the outer being longer than costal cilia. Sc pale and not reaching R1. Thick veins pale yellowish grey, thin veins 4 – 6 grey, 7 very pale. Membrane very lightly tinged grey. Haltere knob yellow. [One specimen has a hair near the tip of vein 1 on both wings].

Female

Frons similar to male but anterolateral bristles a little higher on frons. Labrum and labella as Fig. 19 , the former being yellowish brown and about 1.3x as wide as postpedicel, which is a bit smaller than that of the male. Otherwise head similar to male. Thorax as male, except anterior scutellars subequal to hairs at rear of scutum. Abdominal tergites brownish yellow to light brown. T5 – T7 as Fig. 18 . Venter grey, and with hairs as in male. Sternite 7 a narrow irregular bar about 3.5x as long as wide, with two longer hairs at rear margin and 3 – 4 shorter ones further forward. Posterolateral lobes at rear of sternum 8 largely defined by the notch between them, with 1 – 2 hairs near rear margin that are only a little longer than the 3 – 5 in front of these. Cerci pale and about 2.6x as long as broad. With two rectal papillae. Furca as Fig. 15 . Dufour’s crop mechanism as Fig. 17 . Legs similar to male except dorsal hair palisade of mid tibia extends at least two thirds of length. Wing as male except 0.9 – 1.3 mm long. Costal index 0.31 – 0.35. Costal ratios 1.9 – 2.3: 1. Costal cilia 0.04 – 0.06 mm long. Otherwise it and haltere as male. [One specimen has two hairs at the base of vein 3 on one wing].

Material

HOLOTYPE male, United Arab Emirates, al-Abjan, Malaise trap, 10 – 17.x.2005, A. v H. ( CUMZ, 32 – 143). Paratypes, 1 male as holotype; 1 male, 1 female, as holotype except 22.x. – 9.xi.2005 ( CUMZ, 32 – 148), 1 female, as holotype except 9.xi – 7.xii.2005 ( CUMZ, 32 – 152). 1 male, SSW of ad-Dhaid, 13 – 18.xii.2005 ( CUMZ, 32 – 145). 1 female, Wadi Safad, light trap, 20.xii.2005 – 2.i.2006 ( CUMZ, 32 – 147).

Figures

FIGURES 14 – 17. Megaselia necmera (14) male frons, with bristles represented by their basal sockets only; (15) female furca; (16) left face of male hypopygium (17): female Dufour’s crop mechanism.

FIGURES 18 – 20. Megaselia necmera. (18) female, abdominal tergites 5 – 7; (19) female distiproboscis from above; (20) male distiproboscis from above. Scale bars = 0.1 mm.