304 



Leech and Chandler: Coleoptera 



as in the Pacific Northwest some of the species form 

 races or distinguishable populations in nearly every 

 mountain valley, so that their taxonomy is difficult. 

 Taxonomic characters. — Examination of the male 

 genitalia is almost imperative in making specific 

 identifications. Color, and the sizes and arrangements 

 of the elytral punctures, are of value in Peltodytes 

 and Haliplus, but the characters most used are on 

 the ventral surface (prosternum, metasternum, tro- 

 chanters, hind coxae). Secondary sex characters are 

 found in the claws and tarsal segments of the front 

 and middle legs of the males. The first three segments 

 of the front and middle tarsi- of the males are slightly 

 broadened and/or pedunculate, and clothed beneath 

 with a dense pad of short hairs. 



Key to Neorctlc Genera of Hallplldae 

 Adults 



1. Last segment of palpi cone-shaped, as long as or 

 longer than next to last; hind coxal plates large, 

 only last abdominal stern ite completely exposed; 

 elytra with fine sutural striae in at least apical half 

 (fig. 13:4a) Peltodytes Regimbart 1878 



— Last segment of palpi subulate, shorter than next 

 to last; hind coxal plates smaller, leaving last 3 ab- 

 dominal sternites exposed; elytra without fine sutural 

 striae 2 



2. Pronotum with sides of basal two-thirds nearly parallel; 

 epipleura broad, extending almost to tips of elytra, 

 which are never truncate; metasternum reaching epi- 

 pleura (fig. 13:46) Brychius Thomson 1860 



— Pronotum with sides widest at base, convergent anter- 

 iorly; epipleura evenly narrowed, usually ending near 

 base of last abdominal sternite, never reaching elytral 

 apices; episternum completely separating metasternum 

 from epipleura 3 



3. Median part of prosternum and base of prosternal 

 process forming a plateaulike elevation, at least in 

 part angularly separated from sides of prosternum. 

 Haliplus Latreille 1802 



— Prosternum evenly rounded from side to side 



Apteraliplus Chandler 1943 



Key to Nearctic Genera of Hallplldae 

 Larvae 



1. Each body segment with 2 or more erect, segmented, 

 hollow spine-tipped filaments, each half as long as 

 body (fig. 13:5a); abdomen with 9 segments; ocelli 

 located on a small prominence; front legs chelate, 

 4th segment produced apically and edged with a solid 

 row of small teeth, so that 5th segment and claw 

 can be closed on it, pincherlike (fig. 13:30") 



Peltodytes Regimbart 1878 



— Body spines, except in the 1st instar, never stalked 

 or much longer than the length of 1 body segment; 

 10th abdominal segment produced posteriorly in a 

 forked or unforked horn; front legs, if chelate, with 

 segment less produced and without solid row of small 

 teeth 2 



2. Third antennal segment shorter than 2nd; front legs 

 moderately chelate but 3rd instead of 4th segment 

 produced, edged with 2 blunt teeth; 9th abdominal 

 segment not forked, not strongly curved ventrally, 

 body without conspicuous spines (fig. 13:56) 



Brychius Thomson 1860 



— Third antennal segment 2-3 times as long as 2nd 



3 



3. Third segment of front leg' produced and edged by 

 2 blunt teeth; 9th abdominal segment unforked (ex- 

 cept in 1st instar); body with conspicuous spines 



only at lateral edges Apteraliplus Chandler 1943 



— Front legs weakly to moderately chelate, 4th segment 

 more less produced, usually bearing 2 or 3 spines; 

 body with or without oonspicuous spines (fig. 13:5d) 

 Haliplus Latreille 1802 



Key to Nearctic Genera of Hallplldae 

 Pupae 



The pupae of only a few species of the haliplids are 

 known. The following key is adapted from the one 

 given by Hickman (1930) for certain Michigan species, 

 and that of Guignot (1947) for the French fauna. H.B.L. 



1. Dorsal setae of unequal lengths (fig. 13:3c), most of 

 them arising from more elongate and cylindrical tuber- 

 cles Peltodytes Regimbart 1878 



— Dorsal setae of equal length, mostly arising from 

 short, conical tubercles Haliplus Latreille 1802 



Key to the California Species of Peltodytes 



Adults 



1. Each elytron with a median black callosity on 3rd 

 stria; prosternal process narrowed and grooved between 

 front coxae; metasternum depressed between middle 

 coxae; hind femora reddish-brown, paler apically; 

 elytra not dentate near apex; British Columbia to 

 Baja California, Mexico, eastward to Utah, New Mexico 

 callosus (LeConte) 1852 



— Elytra without callosities; prosternal process slightly 

 narrowed, but not grooved, between front coxae; meta- 

 sternum nearly flat between middle coxae, not de- 

 pressed; each elytron with a small tooth at apical 

 four-fifths; California (fig. 13:4a) 



simplex (LeConte) 1852 



Key to the California Species of Brychius 



Adults 



1. Epipleural sides nearly parallel from hind coxae 

 almost to tip, thence strongly convergent to tip; 

 prosternal elevation sparsely, finely punctured, sides 

 not constricted at anterior edge of front coxae; Sis- 

 kiyou County, north to British Columbia, west to Utah 

 hornii Crotch 1 873 



— Epipleural sides gradually convergent from base of 

 coxae to apex of elytra; prosternal elevation moderately 

 punctate, sides constricted just below anterior edge 

 of front coxae; Humboldt, Mendocino, and Alameda 

 counties pacificus Carr 1928 



Key to the California Species of Haliplus 

 Adults 



1. Pronotum with a basal plica on each side, a little 

 nearer to hind angles than to median line (fig. 13:3c) 



2 



— Pronotum without basal plicae 3 



2. Short, broad species; basal pronotal plicae shorter, 

 less than 1/4 of length measured from plical base along 

 plica to anterior pronotal margin; elytra immaculate 

 except for darkened elytral punctures which may 

 cluster to form indefinite spots; Humboldt County, 





