Genus Colobocerus Parent

Colobocerus Parent, 1933b: 403 . Type species: Colobocerus alchymicus Parent [Australasian], by monotypy.

Remarks. Parent (1933b) erected this monotypic New Zealand genus within the Sympycninae on the basis of the modified first flagellomere of the male of C. alchymicus . Ulrich (1981) transferred Colobocerus to the Dolichopodinae based on an examination of the female paratype of C. alchymicus (MNHN). He did not, however, provide a convincing argument to support this transfer, citing only a similarity in habitus, size, and the possession of thick, pale, stubble­like postocular setae. Ulrich’s placement of Colobocerus in the Dolichopodinae was not followed by Bickel and Dyte (1989) and more recently Bickel (1991) suggested that Colobocerus should probably be synonymized with Sympycnus .

The results of the cladistic analysis support the exclusion of Colobocerus from the Dolichopodinae . Colobocerus lacks several ground plan features of the Dolichopodinae including a dorsally setose scape (character 1), a distinct pedicel condyle (character 3) and a bare male abdominal T6 (character 36), and based on my examination of the male holotype, appears to be a typical sympycnine. In all of the equally parsimonious trees (Fig. 1), C. alchymicus is grouped with the two sympycnine outgroup taxa (i.e. Syntormon pallipes and Sympycnus annulipes) based on the reduction of segment 7 (character 37:1) and the presence of the hypandrial apodeme (character 67:1), supporting the original placement of Colobocerus in the Sympycninae . However, because permission to dissect the genitalia of the male holotype of C. alchymicus was not granted, the condition of segment 7 (character 37) could not be assessed and was scored as “?” in the matrix (Appendix 1). Syntormon pallipes and C. alchymicus are further grouped together based on the possession of a distinct posterior preapical seta on the mid femur (Character 27:1).

Material Examined. Colobocerus alchymicus Parent, [AU]: ɗ holotype (CMNZ), Ψ paratype (MNHN).