Record Details
Larval systematics of the Troginae in North America, with notes on biologies and life histories (Coleoptera: Scarabaeidae)
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Larval systematics of the Troginae in North America, with notes on biologies and life histories (Coleoptera: Scarabaeidae) |
| Names |
Baker, Charles William, 1937-
(creator) Ritcher, Paul O. (advisor) |
| Date Issued | 1966-08-22 (iso8601) |
| Note | Graduation date: 1967 |
| Abstract | A study of the immature stages of the subfamily Troginae in North America was conducted from the spring of 1963 through the spring of 1965, Larvae of Trox and Omorgus were easily reared in the laboratory, but all attempts to rear the larvae of Glaresis were unsuccessful, The suberosus group, one of the five groups of species within the genus Trox in North America as recognized by Vaurie (1955), is given generic status. The 17 species of the suberosus group are placed in the genus Omorgus which was originally proposed by Erichson (1847) with Trox suberosus later designated as the type. The placement of these 17 species in Omorgus is done on the basis of the larval morphology and recent work on the morphology and cytogenetics of the adults. A table listing 17 characters by which the genus Trox may be distinguished from the genus Omorgus is presented. The other four groups of species in North America, as recognized by Vaurie (1955), are retained in the genus Trox. The adults of 22 species of Trox and Omorgus were collected during the summers of 1963, 1964, and 1965, in the states of Oregon, Arizona, New Mexico, and Texas. Cultures of these beetles were established in the laboratory and 595 larvae were reared for the systematic studies of the immature stages. Additional material was borrowed from the U. S. National Museum and Dr. P. O. Ritcher, and the larvae of two species were used for the descriptions. Generic descriptions of the larvae of Trox and Omorgus are given along with brief descriptions of 24 of the 42 species of these genera known to occur in North America. The larvae of the following species are described: T. scaber (L.), T. aequalis Say, T. fascifer LeConte, T. atrox LeConte, T. spinulosus dentibius Robinson, T. foveicollis Harold, T. frontera Vaurie, T. sonorae LeConte, T. robinsoni Vaurie, T. tuberculatus (De Geer), T. plicatus Robinson, T. sordidus LeConte, T. variolatus Melsheimer, T. unistriatus Beauvois, O. suberosus (Fabricius), O. rubricans (Robinson), O. carinatus (Loomis), O. monachus (Herbst), O. fuliginosus (Robinson), O. asper LeConte, O. punctatus (Germar), O. inflatus (Loomis), O. texanus LeConte, O. scutellaris (Say). The general life history of Trox scaber (L.) as it occurs in the laboratory is described and notes on other species are included. A section on the general biology of Trox and Omorgus is given. The method whereby the immature stages of Trox and Omorgus were reared is described. Pertinent morphological characters of the immature stages are presented in 59 figures, and the literature of the immature stages reviewed on a worldwide basis. A key to the third stage larvae is given, but larvae of several closely related species were inseparable and are keyed out in the same couplet. Structures of taxonomic importance include the epipharynx, hypopharynx, antennae, head capsule setation and topography, maxillae, spiracles, and setal and spinule patterns on the thoracic and abdominal lobes and legs. A simplified terminology is utilized for reference to the lobes of the abdominal and thoracic regions. The terms subtorma, subapotorma, and fused phobal mass are proposed to facilitate the description of the larval hypopharynx and epipharynx. A synoptic collection of the larvae utilized in this study has been deposited in the collection of the U. S. National Museum, Washington, D.C. |
| Genre | Thesis/Dissertation |
| Topic | Scarabaeidae -- Larvae |
| Identifier | http://hdl.handle.net/1957/47471 |
