Species Hoplia trivialis - Dark Hoplia
On the tribal classification of the Nearctic Melolonthinae (Coleoptera: Scarabaeidae), with descriptions of new species of AcomaBy Evans A.V., Smith, A.B.T.
Zootaxa 4748: 51–77, 2020
Full title: On the tribal classification of the Nearctic Melolonthinae (Coleoptera: Scarabaeidae), with descriptions of new species of Acoma
The species of Scarabaeidae (Coleoptera) associated with sugarcane in south FloridaBy R.D. Gordon and D.M. Anderson
The Florida Entomologist, 64 (1): 119-138 , 1981
"Those species of Scarabaeidae known to be associated with sugarcane in the Lake Okeechobee area of Florida are discussed and delineated. The species are: Phyllophaga latifrons (LeConte), Anomala marginata (F.), Cyclocephala parallela Casey, Dyscinetus morator (F.), Ligyrus subtropicus (Blatchley), and Euphoria sepulchralis (F.). Descriptions and illustrations of the larvae of all these species are presented as well as descriptions and illustrations of the adults of all species except Euphoria sepulchralis (F.). A key to the south Florida species of the genus Cyclocephala is also included."
The Scarab Beetles of FloridaBy Robert Woodruff
Florida Department of Agriculture and Consumer Services, 1973
Full title: Arthropods of Florida and Neighboring Land Areas. Volume 8. The Scarab Beetles of Florida (Coleoptera: Scarabaeidae). Part I. The Laparosticti (Subfamilies: Scarabaeinae, Aphodiinae, Hybosorinae, Ochodaeinae, Geotrupinae, Acanthocerinae). Part II covers May Beetles (Phyllophaga).
Has black-and-white photos. Apparently out of print, but still available from some suppliers--see comments. Also available on-line:
Link updated 7 February 2012--thanks for the comments!
Aquatic Hydrophilidae and Hydraenidae of Wisconsin (Coleoptera). I.By William L. Hilsenhoff
The Great Lakes Entomologist, 1995
Full title: Aquatic Hydrophilidae and Hydraenidae of Wisconsin (Coleoptera). I. Introduction, Key to Genera of Adults, and Distribution, Habitat, Life Cycle, and Identification of Species of Helophorus Fabricius, Hydrochus Leach, and Berosus Leach (Hydrophilidae), and Hydraenidae