330 



Leech and Chandler: Coleoptera 



(profile) usually before middle; pronotum weakly bi- 

 impressed laterally, sides and margin smooth; 11th 

 elytral striae clearly separated from marginal groove 

 except at extreme base; lateral striae not at all cana- 

 liculate; elytra polished in both sexes; male genitalia 

 (fig. 13:24^); Alaska to California . picipes Aube 1838 



Genus Dineutus MacLeay 



Only one species of Dineutus (subgenus Cyclinus 

 Kirby), has been recorded from California. Specimens 

 seen are labeled "Mecca, Cal., VIII. 15.34." Mecca 

 is in Riverside County, just north of the Salton Sea. 



Length 9 to 10 mm., form oval; front femora of male with 

 a slight angulation and tiny tooth at apical three-fourths on 

 lower anterior margin; apex of median lobe of male genitalia 

 distinctly arched, not flattened, apices of parameres 

 broadly rounded solitarius Aube 1838 



Genus Gyretes Brulld 



In 1852 LeConte described G. sinuatus from "Ad 

 flumen Colorado." In his redescription of 1868 he 

 added "Abundant in the Colorado River, near Fort 

 Yuma, California." In 1907 Regimbart described G. 

 californicus on the basis of a single female labeled 

 only "Californie"; it is not possible to distinguish 

 this from G. sinuatus on the basis of the original 

 description. 



It is peculiar that no modern specimens from Cali- 

 fornia have been seen. 



Elongate-oval, convex, shining; pronotum and elytra with 

 tomentose lateral band, which is narrower basally on 

 elytra than on pronotum, broadening apically and reaching 

 suture at apex in male but not in female (fig. 13:22c) 

 sinuatus LeConte 1852 



REFERENCES 



DIMMOCK, G., and F. KNAB 



1904. Early stages of Carabidae. Springfield (Mass.) 

 Mus. Nat. Hist. Bull., 1:1-56, 4 text figs., pis. 1-4. 

 FALL, H. C. 



1922. The North American species of Gyrinus. Trans. 

 Amer. Ent. Soc., 47:269-306, pi. No. 16. 

 HATCH, M. H. 



1930. Records and new species of Coleoptera from 

 Oklahoma and western Arkansas, with subsidiary 

 studies. Publ. Univ. Oklahoma 3iol. Surv., 2:15-26", 

 2 text figs. 

 1953. The beetles of the Pacific Northwest. Part I: 

 Introduction and Adephaga. Univ. Wash. Publ. Biol., 

 16:vii+l-340, incl. front. 2 text figs., 37 pis. 

 LEECH, H. B. 



1940. Dineutus in California. Pan-Pac. Ent., 16:74. 

 OCHS, G. 



1949. A revision of the Gyrinoidea of Central America. 

 Rev. de Entomologia, 20:253-300. 

 ROBERTS, C. H. 



1895. The species of Dineutes of America north of 

 Mexico. Trans. Amer. Ent. Soc., 22:279-288-, 2 pis. 

 WICIQIAM, H. F. 



1893. Description of the early stages of several North 

 American Coleoptera. Bull. Nat. Hist., Univ. Iowa, 

 2:330-344, pi. IX. 



1894. On some aquatic larvae, with notice of their 



parasites. Canad. Ent., 26:39-41. 

 YOUNG, F. N. 



1954. The water beetles of Florida. Univ. Florida Stud. ; 



Biol. Sci. Ser., 5:ix+238 pp., 3 1 figs. 



Family HYDRAENIDAE 



The species of this family often have been included 

 in the Ilydrophilidae. All hydraenids are small, most 

 of them between 1 and 2.5 mm. long. Many kinds cling 

 to rocks and waterlogged wood in rapid streams, but 

 others crawl among the pebbles and through the debris 

 at the shore line or tunnel in the damp sand nearby. 

 Some occur in brackish waters, and a few in the 

 intertidal zone. They can only creep or run, since 

 their legs are not modified for swimming. The adults 

 are aquatic and largely vegetarian, the larvae more 

 terrestrial than aquatic, and carnivorous. 



Three genera are known from our fauna. Ochthebius 

 has many species; most are beautifully sculptured 



Figu 13:25. a, Berosus dolerosus, adult; b, Helochares sp., 

 antenna; c, Ochthebius sp., antenna; d, Ochthebius interruptus, 

 adult; e, Hydraena needhami (a,d, Leech, 1948; b,c, Crowson, 

 1950; e, D'Orchymont, 1929). 



