Eustrophopsis confinis ( LeConte, 1866 )

Pollock, Darren, 2008, Review of the Canadian Eustrophinae (Coleoptera, Tetratomidae), ZooKeys 2 (2), pp. 261-290 : 280-282

Eustrophopsis confinis ( LeConte, 1866)

( Figs 6 , 13 , 22 , 30 )

Eustrophus confinis LeConte, 1866: 152 .— Horn, 1888: 35; Dury, 1906: 260; Leng, 1920: 238; Csiki, 1924: 10; Hatch, 1965: 66; Poole and Gentili, 1996: 299; LeSage, 1991: 246; Majka and Pollock, 2006: 53. Lectotype (here designated), sex unknown, labelled “Wis / Type 4780 / E. confinis Lec ”, in MCZ.

Diagnosis Eustrophopsis confinis is the only Nearctic species of Eustrophinae with a combination of widely separated eyes, and transverse ridges on the outer surface of the meso- and metatibiae. In fact, it may be the only world Eustrophopsis with widely separated eyes. Also, its almost uniformly dark color separates E. confinis from E. bicolor .

Description TL 4.8-6.1 mm; GEW 2.4-3.1 mm. Body ( Fig. 6 ) ovate, subparallelsided; dorsal and ventral color uniformly dark piceous to black; antennomeres 1-4 and 11 slightly lighter in color than antennomeres 5-10; dorsal pubescence relatively long, conspicuous; eyes ( Fig. 13 ) widely separated (space 1-1.5 x length of antennomere 1), inner margin deeply emarginate; antennomeres ( Fig. 22 ) 5-10 subquadrate; antennal sensilla completely annular (as in Fig. 25 ); last maxillary palpomere unmodified, fusiform; prosternal process triangular, moderately narrowed distally, extended to slightly short of posterior margin of procoxae; prothoracic episternal suture present; elytral punctation coarse, punctures arranged in longitudinal striae ( Fig. 6 ); meso- and metatibiae with oblique ridges (as in Fig. 16 ).

Distribution ( Fig. 30 ) Although specimens are seemingly rarely collected, E. confinis exhibits one of the broadest west-east ranges. Th e species is known from western British Columbia to Nova Scotia. Th e single record from Saskatchewan is the most northerly known specimen of Eustrophinae in North America. US distribution: ID, MI, ME, NE, NH, SD, WI.

Natural history Label data: Polyporus anceps (ME). Chantal (1985) stated that no natural history data were known to him, but that E. confinis should be similar to other members of the group.

Material examined Specimens were examined from the following Canadian localities: BRITISH COLUMBIA: McIntyre Cr., Oliver , 6.VI.1959, R.E. Leech, ( CNC, 1) ; Radium , 4.VI.1953, B.F. & J.L. Carr, lot 5, ( CARR, 3) ; same locality, 4.VI.1953, B.F. & J.L. Carr, lot 5, ( DAPC, 2) ; Trinity Valley , 16.VIII.1927, J.R.L. Howell, ( PFC, 1) ; Vernon , 11.V.1943, H. Leech, on grass, ( UBC, 1) ; Victoria , ( MCZ, 1) ; Tappen, 3.VI.1978, B.F. & J.L. Carr, lot 1, ( DAPC, 1). SASKATCHEWAN: Road 914, 82 km N. Jct. Hwy. 165, 30.VII.1986, B.F. & J.L. Carr, lot 2, ( DAPC, 1). MANITOBA: Duck Mtn. Prov. Pk., 19-24.VI.1981, Ashworth, Schwert & Keller, open gravelly mud with sparse vegetation by water’s edge, ( DAPC, 1) ; Riding Mt. Pk., 2.VI.1938, W.J .

Brown, ( CNC, 1) ; Sandilands Forest, 15.VIII.1993, N.J. Holliday, ( JBWM, 1). ONTARIO: Constance Bay , 16.V.1933, W.J. Brown, ( CNC, 1). NOVA SCOTIA: Cumberland Co., Wentworth, 21.V-5.VII.1965, B. Wright, ( NSMC, 2) .

Figures

Figs 1-7. Dorsal habitus of Canadian eustrophines. Fig. 1. Pseudoholostrophus impressicollis, TL = 4.3 mm; Fig. 2. Pseudoholostrophus discolor, TL = 4.8 mm; Fig. 3. Holostrophus bifasciatus, TL = 5.8 mm; Fig. 4. Eustrophus tomentosus, TL = 4.8 mm; Fig. 5. Eustrophopsis bicolor, TL = 5.6 mm; Fig. 6. Eustrophopsis confinis, TL = 5.4 mm; Fig. 7. Synstrophus repandus, TL = 6.8 mm.

Figs 8-16. Features of Canadian eustrophines. Figs. 8-14. Frontal view of head (same specimens as in Figs. 1-7). Fig. 8. Pseudoholostrophus impressicollis; Fig. 9. Pseudoholostrophus discolor; Fig. 10. Holostrophus bifasciatus; Fig. 11. Eustrophus tomentosus; Fig. 12. Eustrophopsis bicolor; Fig. 13. Eustrophopsis confinis; Fig. 14. Synstrophus repandus. Figs. 15-16. Hind tibia. Fig. 15. H. bifasciatus; Fig. 16. E. tomentosus.

Figs 17-25. Antennae of Canadian eustrophines. Fig. 17. Pseudoholostrophus impressicollis; Fig. 18. Pseudoholostrophus discolor; Fig. 19. Holostrophus bifasciatus; Fig. 20. Eustrophus tomentosus; Fig. 21. Eustrophopsis bicolor; Fig. 22. Eustrophopsis confinis; Fig. 23. Synstrophus repandus; Fig. 24. E. tomentosus, antennomeres 9-11 (sensillar field indicated by stippling); Fig. 25. S. repandus, antennomeres 9-11 (sensillar field indicated by stippling). Scale bar = 0.25 mm (Figs. 17-23); 0.1 mm (Figs. 24-25).

Fig. 30. Canadian distribution of Eustrophopsis confinis. Inset shows US distribution, by state.