315 



Leech and Chandler: Coleoptera 



Genus Hydrovatus 



Adults 



Only one species is recorded from California. Form short, 

 broad, convex (as in fig. 13:14c/); length 2-2.5 mm.; elytra 

 with dual punctation; an oblique raised line across base 

 of each epipleuron, as in Hygrotus and Desmopachria; 



Imperial, Tulare, Fresno, San Joaquin counties 



brevipes Sharp 1882 



Genus Celina 

 Adults 



These are small reddish beetles, 4 to 6 mm. long, of 

 rather narrow and parallel form. The apices of elytra 

 and last abdominal sternite are produced behind, 

 acuminate (fig. 13:146). 



Two California specimens, representing two spe- 

 cies, have been seen. Both were collected near 

 Blythe, Riverside County, and both may be unde- 

 scribed. One is the same as the teneral male recorded 

 from Baja California as "Celina angustata Aube'?" 

 by Leech (1948). 



Key to the California Species of Bldessus 5 

 Adults 



1. Metasternum, hind coxal plates, and first 1 or 2 ab- 

 dominal sternites coarsely punctate, punctures obvi- 

 ously coarser than those of dorsal surface; elytra 

 with 4 large pale areas, or sometimes with antemedian 

 pale areas joined laterally and near suture to smaller 

 postmedian ones; clypeus lightly margined anteriorly 



2 



— Metasternum, and usually hind coxal plates and abdom- 

 minal sternites finely punctate, punctures finer than 

 those of dorsal surface; elytra unicolorous, vittate, 

 quadri maculate, or sexmaculate; clypeus not margined 

 anteriorly (except in male of ornatellus) 6 



2. Each elytron with a slightly oblique rounded long- 

 itudinal carina, continuing to beyond middle from 

 basal plica 3 



— Each elytron with only the usual short impressed basal 

 plica , 4 



3. Inner margin of rounded elytral carinae following 

 directly behind basal plicae; sutural margin usually 

 raised, much more finely punctate than elytral disc; 

 Ventura County, north at least through Mariposa and 

 Lake counties plicipennis (Crotch) 1873 



— Inner margin of elytral carinae following from appreci- 

 ably inward of basal plicae (fig. 13:14c); ^utural 

 margin differentiated by fine punctation but not usually 

 raised; northwest California, Sonoma County, north to 

 southwest Oregon leachi Leech 1948 



4. Pale spots of elytra large, usually occupying more 

 than 1/2 the elytra; sutural dark areas of elytra, separat- 

 ing anterior spots, together about as wide as a com- 

 pound eye; basal plicae of pronotum more deeply 

 impressed, sinuate, equal to or shorter than adjacent 

 elytral plicae 5 



— Pale spots of elytra smaller, occupying less than 1/2 of 



\ 5 Fall (1901) recorded B. cinctellus (LeConte) 1852, from 

 California, on the basis of an old specimen labeled only "So. 

 Cal."; no modern examples have been seen, though it may occur 

 in the region of the Colorado River. It will trace to Couplet 3, 

 but does not fit either choice. Examples of "subtilis" from about 

 the San Francisco Bay area north may be B. subplicatus Hatch 

 1953; if so, the two appear to integrate in a cline. 



Ml* 



SJ7 



Fig. 13:15. Dytiscidae adults, a, Deronecfes deceptus; b, 

 Deronectes eximius; c, Desmopachria cjisperso; d, Desmopachria 

 larissima (a,b, Leech, original; c,d, Young, 1951). 



elytral area; sutural dark parts separating anterior 

 spots each about as wide as an eye; basal plicae of 

 pronotum lightly impressed, almost straight, equal 

 to or longer than adjacent elytral plicae; Santa Barbara 



County to San Diego County 



quadripustulatus Fall 1917 



5. Form almost evenly oval, not much narrower posteriorly; 

 sides of pronotum nearly straight, base very slightly 

 narrower than base of elytra but outline (in dorsal 

 view) not discontinuous; disc of elytra rounded, not 

 flattened; Santa Barbara County, Ventura County 

 pictodes Sharp 1882 



— Form less evenly oval, more parallel-sided, much 

 narrower posteriorly than anteriorly; sides of pronotum 

 arcuate, forming more of a discontinuity in outline 

 with elytral base; disc of elytra flat. (Some specimens 

 show traces of longitudinal carinae and might De run 

 to leachi, but are distinguished by their much finer 

 elytral punctation and very broad anterior tip of 

 metasternum; Sonoma, Mendocino, and Lake counties 



sp. 



6. Each elytron with a shallow sutural stria, area between 

 it and suture raised and more finely punctured than 

 elytral disc; pale markings on elytra in form of spots 

 or fasciae 7 



— Elytra without sutural striae; elytral punctation coarser 

 than that of base of pronotal disc; elytral coloring 

 varying from uniformly piceous, through vittate forms, 

 to almost uniformly luteous; elytra shining between 

 punctures (all males, most females) or alutaceous 

 (some females); Alaska to Argentina 



complex centering around af finis (Say) 1823 



7. Hind coxal plates coarsely punctate, punctures at 

 least twice as large as those on base of disc of pro- 

 notum; elytra coarsely punctate with sparse incon- 

 spicuous fine hairs, appearing glabrous; clypeus 



