Campsicnemus zigzag

Evenhuis, Neal L., 2008, The Campsicnemus lobatus and zigzag groups in the Society Islands, French Polynesia (Diptera: Dolichopodidae), Zootaxa 1910, pp. 27-44 : 37

The zigzag group

Diagnosis. Species in the zigzag group are easily distinguished by the distinctive thick, modified seta on the ventroapical third of the mid femur ( Figs. 14–18 ). No other species of Campsicnemus known have this ventral femoral setal modification. Species in this group are some of the smallest in the genus (from 1.0– 2.3 mm in length).

Remarks. The species in this group are endemic to the Society Islands and, except for two species that are both found on Tahiti ( C. ogradyi , n. sp. and C. zigzag , n. sp.), there appears to be one species per island. If the one-island-one-species formula hold true for the remainder of the Society Islands, further collecting should reveal species of this group on Moorea and Bora Bora.

Although some species were collected in association with rocks in or near streams, they are also found in sweeps of vegetation and are probably more associated with the riparian areas of streams rather than the close association with wet seeps of members of the lobatus group from the Society Islands or actual water skaters of the members of the Campsicnemus described from the Marquesas.

Included species:

mylloseta Evenhuis , n. sp. (Society Islands [Huahine]).

ogradyi Evenhuis , n. sp. (Society Islands [Tahiti]).

ostlinx Evenhuis , n. sp. (Society Islands [Raiatea]).

tahaanus Evenhuis , n. sp. (Society Islands [Tahaa]).

zigzag Evenhuis , n. sp. (Society Islands [Tahiti]).

Figures

FIGURES 14 – 18. Campsicnemus zigzag group male mid femur. 14. C. mylloseta; 15. C. ogradyi; 16. C. ostlinx; 17. C. tahaanus; 18. C. zigzag.