1a. Antennae filiform, compressed; palps with ultimate
segment securiform; appendages not retractile; tarsomere 3 with large
fleshy lobe; integument appearing glabrous, rutocastaneus to piceous.
. . . . . . . . . 2
1b. Antennae short, clavate or capitate; palps with ultimate
segment fusiform or pyriform. . . . . . . . . . . . 3
2a. Usually larger, 8-12 mm, elongate; integument usually
rufocastaneus with metallic cupreous sheen, occasionally with
viridescent reflections; coastal coniferous forests of Oregon and
northern California. . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Amphicyrta chrysomelina Erichson
2b. Usually smaller, 5-10 mm, ovoid, occasionally inflated
posteriorly; integument rufopiceous to piceous, without metallic
sheen; prairies and oak-pine woodlands of central California and
southwestern Oregon . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Amphicyrta dentipes Erichson
3a. Antennae capitate; body small (0.9-2.6
mm), shallowly to moderately convex; appendages closely retractile;
dorsum with clavate or truncate bristles. . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . 4
3b. Antennae clavate; body various (1.9-10.0 mm), moderately to
strongly convex; ovate to elongate; appendages not or partially
received into fossae; dorsum with decumbent to erect fine setae. . .
. . . . . . .10
4a. Length 2.4-3.2 mm; ovoid, dorsum with
appressed scale like setae and erect bristles . . . . . . . . . . . .
5
4b. Length 0.9-2.1 mm; ovate, strongly convex; elytral striae
punctate; dorsum with bristles only; northern U.S. and southern
Canada, Europe. . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . .Chaetophora spinosa (Rossi)
5a. Ovate to oval, shallowly to moderately
convex, lateral margins arcuate; striae on disc shallowly impressed,
or serially punctate. . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6
5b. Elongate, strongly convex, parallel sided; elytra with
striae deeply punctate and impressed, sulciform; central and southern
California, Baja California Norte . . . . . . . . . . . . . . . .
.Sierraclava cooperi Johnson
6a. Length 2.1-2.8 mm; subparallel laterally;
appressed squamae linear; median lobe of aedeagus slender, narrowly
acuminate apically; Alaska. . . . . . . . . . . . . . . . . .
Curimopsis setulosa (Mannerheim)
6b. Length 2.8-3.2 mm; oval in lateral outline; aedeagus not as above
. . . . . . . . . . . . . . . . . . . . . . . . . . . 7
7a. Dorsal squamae round, set into round punctures;
3.0-3.2 mm; subparallel laterally; western and northern U.S., Canada
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.Curimopsis albonotata (LeConte)
7b. Dorsal squamae more or less linear to narrowly subtriangular,
emergent from small usually barely evident punctures; usually
smaller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . .8
8a. Body oval, rounded laterally; striae not
impressed as lines or shallow sulci, usually represented by rows of
punctures; south central U.S. . . .. . . . . . . . . . . . . . . . .
. . . . . . . . . .Curimopsis strigosa (Melsheimer)
8b. Body elongate, subparallel laterally; striae narrowly, shallowly
impressed, not evidently punctate. . . . 9
9a. Length 2.9-3.2 mm; appressed squamae short,
subtriangular; elytral apical declivity long, gradually sloping;
sutural strict at declivity shallowly impressed; northeasternU.S.,
Canada, Alaska . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . Curimopsis moosilauke Johnson
9b. Length 2.8-2.9 mm; appressed squamae longer, linear; elytral
apical declivity shorter, abruptly sloping; sutural strict at
declivity distinctly and deeply impressed, sulcate; northern U.S.,
Canada, Alaska . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. Curimopsis echinata (LeConte)
10a. Frontal margin beaded, occasionally reflexed
and carinate; mesosternum strongly reduced except for median fossa;
palps with ultimate segment fusiform to narrowly pyriform; metacoxae
small, distant from elytral margin; elytra often connate . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . .11
10b. Frontal margin rounded or truncate, never reflexed, beaded or
carinate; mesosternum distinct laterad of median fossa; palps with
ultimate segment compressed or cylindrically pyriform; metacoxae
flattened, nearly reaching elytral margin; elytra not connate. . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . .19
11 a. Elytra separate and metathoracic wings
present; integument rufopiceous to piceous, occasionally with
submetallic reflection; mesocoxae moderately separated . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
11b. Elytra connate, metathorax apterous; mesocoxae widely separated
. . . . . . . . . . . . . . . . . . . . . . . 14
12a. Form short, ovate, slightly depressed
dorsally; elytral pubescence long, moderately dense, evenly
distributed; elytral strict becoming evanescent at midlength;
northeastern U.S., southeastern and southwestern Canada. . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Simplocaria semistriata (F.)
12b. Form elongate, ovoid; elytral pubescence tessellate; elytral
striae complete or becoming evanescent preapically. . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . .13
13a. Length 3.5-4.5 mm; pronotal punctures fine and
sparse on disc; elytral striae becoming evanescent towards apex;
pubescence decumbent; northern Canada, Greenland, Eurasia. . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Simplocaria elongata J. Sahlberg
13b. Length 2.8-3.5 mm; pronotal punctures moderate on disc; elytral
striae complete to apex; pubescence recumbent to suberect; northern
U.S., Canada, Greenland, Eurasia. . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . Simplocaria
metallica (Sturm)
14a. Pubescence simple, slender, fine; epipleura
flat; integument shining to metallic. . . . . . . . . . . . . . . .
.16
14b. Pubescence stout, recurved; epipleura deeply emarginate to
receive femoral knee; integument brunneous. . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . 15
15a. Length 1.8-2.3 mm; lateral elytral margin
crenate anteriorly; coastal Oregon, Washington, British Columbia. . .
. . . . . . . . . . . . . . . . . . . . . .Exomella pleuralis
(Casey)
15b. Length 2.3-2.4 mm; lateral elytral margin smooth throughout;
northern Idaho . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . Exomella
merickeli Johnson
16a. Epipleura broad, extending length of elytron;
dorsal integument piceous to olivaceous, shining . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . 17
16b. Epipleura narrow, attenuating and terminating before second
visible abdominal sternite; dorsal integument viridescent . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . .18
17a. Larger, 3.2-4.1 mm, lateral margins inflated;
integument piceous, shining, occasionally with submetallic
reflections; pubescent sparse to moderate, short to long; north
coastal California to southeastern Alaska, and west of Cascade Range
crest in Oregon, Washington, British Columbia . . . . . . . . . . . .
. . . . . . . Lioon simplicipes (Mannerheim)
17b. Smaller, 2.9-3.6 mm, lateral margins weakly rounded; integument
piceous, olivaceous, without submetallic reflections; pubescence
moderately dense, long; northern Idaho. . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . Lioon nezperce Johnson
18a. Length 2.4-2.6 mm; dorsal integument bright
viridescent; west of Cascade Range crest in Oregon, Washington,
British Columbia . . . . . . . . . . . . .Lioligus nitidus
(Motschulsky)
18b. Length 2.2-2.4 mm; dorsal integument olivaceous with evanescent
viridescent reflections; northern Idaho . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . .Lioligus pallidus Casey
19a. Frontal margin truncate and thickened;
abdominal sternite 1 without crural modifications . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . .20
19b. Frontal margin obtusely rounded; abdominal sternite 1 with
distinct crural depressions or fossae . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . 22
20a. Form subparallel, moderately convex dorsally;
piceous, without metallic patches or reflections; pubescence long;
decumbent, with erect black setae; northern U.S., Canada, Greenland .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.Arctobyrrhus subcanus (LeConte)
20b. Form ovoid to subparallel laterally, strongly convex dorsally;
piceous, frequently with cupreous or viridescent patches or
intervals; pubescence short, oppressed, without erect setae . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . 21
21a. Form ovoid, short; integument rarely with
cupreous or viridescent patches; pubescence black and cinereous,
tessellate on alternate elytral intervals; transcontinental . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . Cytilus alternatus
(Say)
21b. Form elongate to subparallel; elytra usually with
viridescent patches or intervals; pubescence pale cinereous, rarely
tessellate; montane western U.S. and Canada . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . Cytilus mimicus Casey
22a. Tarsomere 4 with membranous ventral lobe; dorsal integument
shining, usually viridescent and/or cupreous . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.23
22b. Tarsi simple; dorsal integument opaque or shining, piceous to
black . . . . . . . . . . . . . .27
23a. Form ovate; aeneous to viridescent; punctures fine to
obsolescent, or coarse and forming rugose patches on elytra;
pubescence minute or moderately long and patchy, usually mixed
cinerous and rufobrunneous . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . 24
23b. Form subparallel; piceous with viridescent reflections to
cupreous; punctures fine to moderate; pubescence moderately long,
evenly distributed . . . . . . . . . . . . . . . . . . . . .
.26
24a. Length 6.5-10.0 mm; dorsal punctures fine;
subglabrous, pubescence minute; aeneous to viridescent, with elytra
bearing distinct aeneous and viridiaeneous vittae; northern Idaho,
northeastern Washington, western Montana, southeastern British
Columbia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . Eusomalia
lecontei (Wickham)
24b. Length 3.2-4.0 mm; punctures coarse, pubescence usually evident,
moderately long. . . . . . . . . . . . . . . . . . .25
25a. Dorsal punctures small to moderately coarse,
simple, forming rugose patches with little suggestion of strial
formation, or smooth with finely punctate striae on elytra; aeneous
to viridiaeneous, often vittate on elytra; northcoastal California to
Sitka, Alaska, west of Cascade Range crest in Oregon, Washington,
British Columbia . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Listemus acuminatus (Mannerheim)
25b. Dorsal punctures large, coarse, umbilicate, not condensing into
rugose patches on elytra; piceous, with only faint aeneous
reflections; northern Idaho, northeastern Washington. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Listemus kootenai Johnson
26a. Integument piceous, frequently with
viridescent reflection; punctures moderate to dense; pubescence
cinereous with dark brunneous patches; montane western U.S., Canada. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Morychus aeneolus (LeConte)
26b. Integument aeneous to cupreous, occasionally with viridescent
reflections; punctures fine to moderately dense, moderately to
sparsely distributed; pubescence mixed rufobrunneous and cinereous;
western U.S. and Canada. . . . . . . . . . . . . . . . . . Morychus oblongus (LeConte)
27a. Form oval to subparallel, strongly convex
dorsally; pubescence simple, appressed . . . . . . . . . . . . . . . . . . . 28
27b. Form ovate, shallowly convex dorsally; pubescence including
erect, bristle like setae; central and eastern U.S., southern Canada
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. Porcinolus undatus (Melsheimer)
28b. Pronotal and elytral integument dulled due to
dense, fine to coarse microreticulation or micorugosities; punctures
small, often obliterated. . . . . . . . . . . . . . . . 29
28a. Pronotal and elytral integument shining between moderate sized
punctures; sparsely and finely microreticulate. . . . . . . . . . . . . . . . 32
29a. Pronotal punctures smaller, well separated on
disc by interspaces greater than own diameter. . . . . . . . . . . . . . . . 30
29b. Pronotal punctures larger, separated by less than own diameter;
northern U.S., Canada . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . Byrrhus geminatus LeConte
30a. Punctures of head coarse, confluent, rugose;
similar but shallower on elytra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
30b. Punctures of head large and shallow on frons; deep and
moderately dense on elytra; north ern U.S., Canada. . . . . . . . . . . . . . . . . . Byrrhus
cyclophorus Kirby
31a. Punctures on pronotal disc small, subequal or
only slightly larger in diameter than base of seta; northeastern U.
S., southeastern Canada. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Byrrhus americanus LeConte
31b. Punctures on pronotal disc larger, 2-3x wider than seta;
northern Canada, Eurasia . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . Byrrhus pilula L.
32a. Punctures on elytra larger, distinct;
sculpturing weak 33
32b. Punctures on elytra minute, often obliterated; sculpturing
transverse, reticulate, microrugose, or undulating; northeastern
U.S., Canada. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Byrrhus concolor Kirby
33a. Length more than 6.5 mm; elytral punctures
smaller, dense but separated, rarely rugulose; northern and western
U.S., Canada . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . Byrrhus kirbyi LeConte
33b. Length less than 6.0 mm; elytral punctures dense, usually
coalesced, rugulose; western U.S. and Canada. . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Byrrhus eximius LeConte