Chonocephalus primus Schmitz

Disney, R. Henry L., 2002, Revisionary notes on Chonocephalus Wandolleck (Diptera: Phoridae) with keys to species of the Holarctic Region, Zootaxa 60, pp. 1-36 : 30-31

Chonocephalus primus Schmitz

Chonocephalus primus Schmitz, 1928: 101 .

Chonocephalus quartus Schmitz, 1928: 104 . Syn. nov.

A slide mounted female in the Museum Koenig (labelled ‘No. 36 Type No. 1’) has been designated the LECTOTYPE in order to stablise its nomenclature. The lectotype of C. secundus is mounted on the same slide (see below).

The female of this species is easily recognised by its distinctive furca (sternite 9) and small eyes. However, Schmitz’s mounting of the lectotype in Balsam caused severe bleaching of the furca.

Schmitz (1928) describes a ‘ Chonocephalus primus var.?’, and also refers to it as ‘Nr 1a’, from a single female (in MKB) mounted on a slide, with its detached palps mounted on two further slides. This proves to be a typical C. primus . The differences from the lectotype noted by Schmitz are now seen to lie well within the range of variation for the series of fresh specimens now available.

Schmitz (1928) also described C. quartus from, the same locality, but I failed to find a type specimen in the MKB. In describing this species he compared it with C. tertius , despite the fact that his description shows it to be nearer his description of C. primus . Thus the latter and C. quartus both have fewer than ten ommatidia in each eye, while C. secundus and C. tertius both have at least a dozen. Furthermore the measurements given for C. quartus closely resemble those he gave for C. primus . Nevertheless, two measurements differ significantly. He gave the length of the arista of C. quartus as 0.28 mm, but as 0.15 mm for C. primus . However, in the slide mount of the lectotype of C. primus it is found to be>0.25 mm, but discernment of the distal portion requires critical lighting. For the lengths of the abdomens (to the rear margin of T7) Schmitz’s measurements were 0.86 mm for C. quartus and 0.65 mm for C. primus . However, this measure is found to be variable in the series of further specimens of C. primus now available (see below), partly due to the degree of extension of the abdomen. Thus it sometimes exceeds 0.8 mm. I conclude, therefore, that as there is no reliable feature that is known to distinguish the descriptions of these two species, C. quartus is therefore proposed as a synonym of C. primus .

This species is probably the unknown female of C. palposus , but it might be that the unknown male of C. primus is C. dimidiatus .

Material

Female lectotype, Bismarck Archipelago (MKB ­ 27­135); female of C. quartus, Neupommern , 28 May­1 June 1896; variety ‘Nr 1a’, 1 female, Lowon W., 23 October­3 November; 1 female, Waldtal W., 2­10 February 1897.