Proceroplatus preziosii Evenhuis & Penney

Penney, David, Evenhuis, Neal L. & Green, David I., 2013, A new species of Proceroplatus Edwards (Diptera: Keroplatidae) in Miocene amber from the Dominican Republic, Zootaxa 3686 (5), pp. 593-599 : 595-597

Proceroplatus preziosii Evenhuis & Penney , new species

Fig. 1 A–G

Type material. Holotype male ( BPBM 17,647) from DOMINICAN REPUBLIC: La Bucara amber mine. Miocene.

Diagnosis. The U-shaped wing pattern ( Fig. 1 A, E) and the genitalia, notably the long, thin gonostylus with a strongly sclerotized acute black apex ( Fig. 1 F, G) distinguish the new species from its described congeners.

Comments. Using the key to Neotropical Proceroplatus in Lane (1950), this species keys to P. variventris Edwards 1931 from Bolivia but is distinguished by the dark halteres (yellow in P. variventris ). It is also close in appearance to P. pictipennis (Williston) on the basis of abdominal pattern but can be distinguished from it based on the distinctly different wing pattern (not U-shaped in P. pictipennis ) and the long, thin gonostyli (short and thick in P. p i c t i p e n n i s). It is also easily distinguished from the only other known amber fossil species of Proceroplatus from Dominican amber, P. h e n n i g i Schmalfuss, 1979, by the different wing pattern (not U-shaped in P. hennigi ), the different abdominal pattern (tergites mostly black in P. hennigi ) and the male genitalia (gonostylus shorter and thicker in P. hennigi ).

Etymology. The specific epithet is a patronym in honour of Prof. Richard F. Preziosi (University of Manchester) for his continued support of DP’s research projects.

Description. Lengths: Body: 3.6 mm; wing; 3.4 mm. Male (Habitus Fig. 1 A). Head. Hollowed out. Right compound eye damaged, almost gone with only outer rim extant, appearing as though it was eaten or decayed over time. Occiput brownish black with short black setae dorsally and near eye margin, setae about equal in length to scape, curved forward. Three ocelli on slightly raised black ocellar tubercle, lateral ocelli large, equal in diameter to 3 ommatidia, medial ocellus punctiform, lateral ocellus 1.5× its own diameter from eye margin. Frons dark brown. Antennae: scape and pedicel discoid, scape brownish black, pedicel yellow. Flagellum: segments 1–9 compressed, wider than high, segments 10–13 subquadrate, terminal segment (14) longer than wide with papillate apex. Flagellomeres brownish yellow, darker brownish yellow on dorsal and ventral edges. Face brownish black, palp three-segmented, thin, dark brownish black, with sparse short hair-like setae on palpomeres 1 and 2 ( Fig. 1 B), setal length one-fifth length of apical palpomere.

Thorax. Prothorax, scutum, scutellum, and mediotergite yellowish ( Fig. 1 C). Pleurae and laterotergite brownish black, latter with white hair-like setae. Mesoscutum with short hair-like setae uniformly distributed, longer setae laterally on humeral callus and in prealar and prescutellar areas, tuft of long setae laterally in supraalar area. Scutellum with long setae on posterior margin. Mediotergite bare. Anepisternum brownish, with group of small dorsal setae, katepisternum light brown. Haltere stem brown, knob dark brown.

Legs. Yellow with tarsi yellowish brown. Coxae setate laterally, fore coxa dense along entire length, mid coxa setate on apical one-half, hind coxa with 10 sparsely distributed setae along entire length, tuft of dense setae apically. Femora with tiny hair-like setae along ventral margin. Spurs black; inner (anterior) ones minute; outer (posterior) ones on foreleg minute, on mid and hind legs very long, 3× length of foreleg spur ( Fig. 1 D). Tibiae with setae in regular rows.

Wing ( Fig. 1 E). Greyish hyaline with grey-brown pattern of infuscation as follows: first band of infuscation from end of vein Sc to vein A1, uninterrupted, widening slightly at contact with veins, narrowing in wing field; second band of infuscation from R2+3 down to M2, uninterrupted; slight infuscation along A1 making it appear that wing infuscation pattern is U-shaped. Costa ending halfway between R4+5 and M1; base of M2 effaced, meeting M1 as fold. Sc and R2+3 setulate along dorsal surface, setulae ending on R2+3 shortly before wing margin.

Abdomen. Tergite I yellowish brown (but cleared so this may be an artefact of decay over time), with black hairs dorsally and laterally. Tergites II–VI black on anterior third, yellowish on posterior two-thirds, black setae sparse, uniformly distributed. Sternites with same colour pattern as tergites.

Hypopygium. Ninth tergite shorter than gonocoxite, wider than long, concave basally, slightly convex apically. Cerci wide, subtriangular with rounded corners. Gonocoxite simple, with V-shaped ventral notch, with patch of dense setae at posteromesal corner, quite setate throughout with longest setae laterally. Gonostylus ( Fig. 1 F–G) longer than gonocoxite, thin, with strongly sclerotized acute black apex, mesal surface without mesal tooth. Distribution. Miocene Dominican amber (La Bucara amber mine).

Figures

FIGURE 1. Proceroplatus preziosii Evenhuis & Penney, new species (holotype male BPBM 17,647) in Miocene Dominican amber. A: Habitus, B: Head, C: Thorax, D: Legs, E: Wing, F: Genitalia, G: Gonostylus. Total body length = 3.6 mm.