Megaselia hortenensis, DISNEY, 2020

DISNEY, R. Henry L., 2020, Scuttle flies (Diptera: Phoridae) from the canopies of ash trees in Norway, with six new species, Fragmenta Faunistica 63 (1), pp. 29-45 : 34-36

Megaselia hortenensis n. sp.

( Figs 24–35 )

Diagnosis (male). Recognition. In the key to the males of Megaselia from the British Isles ( Disney 1989) it runs to couplet 139, but its hyopygium clearly differs from both options. Six additional species run to the same couplet but the hypopygia of all differ as well as in other details such as the mesopleuron having a bristle as well as hairs and/or a longer costal index and/or more numerous axillary bristles, etc. In the key of Schmitz & Delage (1974) to the Palaearctic species of Abteilung V it runs to couplet 15, but the hypopygia differ. In Borgmeier’s (1964) key to Nearctic species of Group IV it runs to couplet 20 lead 1, but its hypopygium is different; and likewise for the rest of the world fauna.

Male. Frons as Fig. 24 , with dense but very fine microtrichia. Cheek with 3 bristles and jowl with 3 that are longer and more robust. Postpedicels ( Fig. 26 ), without SPS vesicles, palps and proboscis as Fig. 25 , the labella with only a few short spinules below. Thorax brown. Three notopleural bristles with no cleft in front of these mesopleuron with only 3 small hairs Fig. 27 . Scutellum (Fig. 28) with an anterior pair of small hairs and a posterior pair of bristles. Abdominal tergites brown as Fig. Hypopygium as Figs 30–32 . Legs dusky yellow to paler. Fore tarsus ( Fig. 33 ) with posterodorsal hair palisade on segments 1–4 and 5 clearly longer than 4. Dorsal hair palisade of mid tibia extends about 0.62–0.63 its length. Hind leg as Fig. 34 , the hairs below the basal half of the femur being shorter than those of anteroventral row of outer half. Hind tibia with about 20 weakly differentiated posterodorsal hairs, without anterodorsals, and spinules of apical combs simple. Wings ( Fig. 35 ) 1.13–1.14 mm long. Costal index 0.39–0.42. Costal ratios 3.25–4.58: 1.08–1.54: 1. Costal cilia (of section 3) 0.7 mm long. No vein 3 hair. 2 unequal axillary bristles, the outermost being 0.07–0.09 mm long. Haltere brown.

Material. Holotype male, Norway, Vestfold, Horten , 59.3654ºN, 10.4611ºE; 18 Jul 2018 , J. Svetlik & L. Børjia (9A, UCMZ, 39–93). Paratype male, as holotype except (6A) 59.3644ºN, 10.4605ºE .

Etymology. Named after Horten in which the type locality is situated.

Figures

Figs 24–27. Megaselia hortenensis n. sp., male. 24 – frons; 25 – postpedicels, palps and proboscis; 26 – postpedicel; 27 – mesopleuron and notopleuron;

Figs 28–35. Megaselia hortenensis n. sp., male. 28 –scutellum; 29 – abdomen; 30 – left face of hypopygium; 31 – left face of hypandrium and penis complex; 32 – right face of hypopygium; 33 – front tarsus; 34 – hind leg; 35 – wing.