Ceratomerus hibernus, Bradley J Sinclair, 2003

Bradley J Sinclair, 2003, Taxonomy, Phylogeny and Zoogeography of the Subfamily Ceratomerinae of Australia (Diptera: Empidoidea), Records of the Australian Museum 55, pp. 1-44 : 29

Ceratomerus hibernus n.sp.

Figs. 78, 79, 81, 100

Type material. HOLOTYPE ♀, “ AUST [ralia]: TAS[mania]: Pelion Hut / 3 km S Mt. Oakleigh / 41°50'S 146°03'E, 860 m / June 1990; I.D. Naumann ”; “ HOLOTYPE / Ceratomerus / hibernus / Sinclair [red label]” ( ANIC) . PARATYPES: Tasmania: 6♀♀, same data as holotype ( ANIC) ; 6♀♀, 28 km SSW Mole Ck , 570 m, MAP 8114 355.752, 15.x.1985, L. Hill ( AMS, ZFMK) .

Diagnosis. Distinguished from other species in this group by the short postocellar setae, long pedicel (three-fifths length of scape) and median fork separated from radial fork by more than the length of crossvein dm-cu.

Description. Wing length 3–3.3 mm, similar to C. falcatus except as follows:

Female. Head dark brown; postocellar bristle slender, less than half length of ocellar bristle; 3 pairs of long vertical bristles, third pair distant from others; postocular bristles long, overlapping at least one-third of eye. Antenna with scape equal to height of eye, with 2–3 long, dorsal setae and 1 long ventral seta; pedicel with short basal section, three-fifths length of scape, with posterior fringe of long setae; postpedicel apical half strongly tapered, extending parallel-sided to short, stout, three-segmented stylus, subequal to one-third length of postpedicel. Palpus light brown, slender, one-fifth length of labrum.

Thorax. Mesonotum, pleura and postnotum brown; 1 slender, short pal. Antepronotum with 2 short setulae.

Wing ( Fig. 81). Medial fork proximal to radial fork by more than length of crossvein dm-cu. Halter with dark knob.

Legs. Coxae and basal half of femora yellowish-brown, remaining leg segments brown, gradually darkening towards tip. Fore coxa lacking modified setae. Fore femur slightly swollen, lacking modified ventral setae. Fore tibia nearly equal in length to femur; apex with undilated anteroapical comb. First tarsomere slightly longer than half length of fore tibia; distal 4 tarsomeres slender, longer than first tarsomere.

Mid tibia slightly shorter than femur with dorsal and ventral apical seta. First tarsomere shorter than remaining 4 tarsomeres.

Hind tibia with 3–4 erect ad setae on apical half; lacking dorsal setae.

Abdomen as in female C. falcatus .

Terminalia ( Fig. 79).Anterior margin ofT10 bearing biserial row of stout, straight spine-like setae; cercus with slender setae, lacking spine-like setae. Spermathecal receptacle spherical, with very short neck where duct attached ( Fig. 78).

Male. Unknown.

Distribution. This species is known only from the northwestern highlands of Tasmania ( Fig. 100) and is possibly restricted to the cooler months (June, October).

Etymology. The specific name is from the Latin hibernus (of winter), referring to the probable seasonality of this species.

Remarks. It is normally not recommended to describe a new species on the basis of female specimens alone. But given the long series of specimens and its apparent differences with C. ordinatus (the only other species of the C. ordinatus group in Tasmania), it was considered best to described this species to encourage “off season collecting” in the hope that conspecific males may someday be obtained.