Key to the Genera of Omaliinae

1. Last segment of maxillary palpus very slender, less than one-half the length of penultimate,

not longer than width of penultimate (Coryphiini). Last segment of maxillary palpus usually

not narrower than penultimate, always longer than width of penultimate. . . . . . . . . . . . . . .. 8

2(1). Pronotum longer than wide . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... ..Boreaphilus Sahlberg

Pronotum not longer than wide . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . .3

3 (2). Head without nuchal constriction. . . . . . . . ... .. . .... . . . . . . . . . . . . . . . . . Haida Keen

Head with nuchal constriction. . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... 4

4(3). Head wider than pronotum. . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . 5

Head not wider than pronotum . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ...6

5(4). Sides of pronotum serrulate... . . . ... . . . . ... .. . ... . . . ... .. . .... . ... .Ephilinus Cockerell

Sides of pronotum entire. . . . . . . . . . . ... .. . .. . . . . . . . . . . . . . . . Occiephilinus Hatch

6(4). Eyes about as prominent as tempora . . .. . . . . . . . ... .. . ... . . .... ... .. ..Subhaida Hatch

Eyes more prominent than tempora . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... 7

7(6). Sides of pronotum angulate at middle.. ... .. . ... .. . ... . . . ... .. .. .Eudectus Redtenbacher

- Sides of pronotum not angulate at middle. . . . . . . . . ... .. . ... . . . ... . . . Pseudohaida Hatch

8(1). Tarsus with the first four segments wider than fifth and with long hairs beneath; head

without nuchal constriction; pronotum usually densely reticulate. . . . . . . . . (Eusphalerini)

... . . . ... .. . ... . . . ... . . . ... .. . ... . . . ... . . . ... .. . ... . . . ... . . . . Eusphalerum Kraatz

Tarsus with the first four segments not wider than fifth, usually without long hairs beneath .

. . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . .9

9(8). Last segment of posterior tarsus shorter than first four together; segment two to four

usually decreasing in length. . . . . ... .. . ... . (Anthophagini)- . . . ... .. . ... . . . ... .. . ... 10

Last segment of posterior tarsus as long as or longer than first four together, first four

segments subequal in length. . . . . . . . ... .. . ... . (Omaliini)- . . . ... .. . ... . . . ... .. . ... 32

10(9). First segment of posterior tarsus about as long as, or longer than last segment. . . ... . 11

First segment of posterior tarsus shorter than last segment. . . . . . . . . . ... .. . ... . . . . 16

11 (10). Last segment of maxillary palpus not more than twice as long as penultimate . . . ... .12

Last segment of maxillary palpus more than twice as long as penultimate. . . ... .. . 14

12(11).Last segment of maxillary palpus not distinctly narrower than penultimate . . . ... .. . ...13

Last segment of maxillary palpus distinctly narrower than penultimate .. . ... . . . ... ..

.. . ... . . . ... .. .. . ... . . . ... .. .. . ... . . . ... .. .. . ... . . . ... .. .. . ... . . Orobanus LeConte

13(12). Penultimate tarsomere bilobed . . . ... .. . ... . . . ... .. . ... . . . ... .Pelecomalium Casey

Penultimate tarsomere not bilobed . . . . . ... .. .. . . . . . . . . . . . . Amphichroum Kraatz

14(11). Head with impressed nuchal line . . . . . ... . . . . . . . . . . . . . . . . . . . . . Unamis Casey

Head without nuchal line . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . ... .15

15(14). Head with a pair of ocelli between eyes. .. . . . ... .. . ... . . .Phlaeopterus Motschulsky

Head without ocelli. . . ... .. . ... . . . ... .. . ... . . . ... .. . ... . . . .. .. . ... . . Vellica Casey

16 (10). Last segment of maxillary palpus narrower than apex of penultimate. . . .. . ... . . . 17

- Last segment of maxillary palpus not narrower than apex of penultimate. . . ... .. . .. . . ... 18