Gnathaphanus picipes (MacLeay)

Liebherr, James K., 2009, Native And Alien Carabidae (Coleoptera) Share Lanai, An Ecologically Devastated Island, The Coleopterists Bulletin 63 (4), pp. 383-411 : 403-404

Gnathaphanus picipes (MacLeay)

( Fig. 6E , 7B )

Diagnosis. Easily distinguished among Hawaiian Harpalini by the presence of five to eight dorsal elytral setae in the third elytral interval, two to three of the setae situated very near the elytral apex, in combination with a glabrous fifth elytral stria. As in G. multipunctatus , the tibiae and tarsi are flavous, however, in contrast to that species the femora are darker, brunneous, and concolorous with the body venter. Standardized body length 9.4–11.2 mm.

Lanai Distribution. This Australian and New Guinean species ( Darlington 1968; Moore et al. 1987) was first collected on Lanai in Maunalei Gulch, 490 m elevation, 3 May 1993 (Liebherr, CUIC). The specimen comprises a pterothorax and abdomen collected under a spider web suspended from the water pipe coming out of the Gulch headwall. Samuelson et al. (1997) report a 1995 Maunalei Gulch specimen as the first Lanai record. Subsequently, the species has been collected across a broad distribution on Lanai ( Fig. 6E ) including the cloud forest, mesic forest, and dry forest communities ( Fig. 1 ).

Habitat. This species has been collected at the following anthropogenically disturbed sites (CUIC): 1) the seasonally dry Maunalei Gulch bottom; 2) running on a sidewalk at the Lanai Airport; 3) in the company of G. multipunctatus running on a clay road after dark at the Kanepuu Dry Forest; 4) under a rock along the road at Puu Aalii on the summit ridge; 5) dead on the road adjacent to a Pinus plantation at Haalelepaakai; and 6) in company with M. buchanani under bark of downed Eucalyptus trunks near Lehua, 683 m elevation on the southeastern end of the summit ridge. On one occasion this species was collected with native species— B. depressa , B. filipes , and M. filipes —by beating soft understory fern in cloud forest.

Figures

Fig. 6. Known distributions of carabid beetle species on Lanai. A. Blackburnia lanaihalensis. B. B. depressa. C. B. filipes. D. Metacolpodes buchanani. E. Gnathaphanus picipes (small circles), G. picipes plus G. multipunctatus (larger bullseye). F. Perigona nigriceps.

Fig. 7. Non-native carabid beetle species known from Lanai (vignettes represent actual body size). A. Metacolpodes buchanani. B. Gnathaphanus picipes. C. G. multipunctatus. D. Perigona nigriceps.

Fig. 1. Pre-Polynesian vegetation communities on the island of Lanai (after Hobdy 1993): 1) cloud forest; 2) mesic forest; 3) dry forest; 4) arid grassland and shrubland; 5) coast and strand.