Degree Type

Dissertation

Date of Award

1985

Degree Name

Doctor of Philosophy

Department

Entomology

Abstract

Studies on the anatomy of the armoured ground cricket, Acanthoplus speiseri Brancsik 1895, were conducted. The external morphology and endoskeletal processes are of the generalized tettigoniid type except that this species is apterus, ocelli are absent and the eyes bear fixed stalks. In the males, the mesonotum has modified tegmina that serve as stridulating organs, while in the females these structures are absent, being represented only by vestigial wing pads. The thoracic musculature of A. speiseri is similar to that of Acridopeza reticulata Guerin, Neoconocephalus robustus (Scudder) and Homorocoryphus nitidulus vicinus (Walker), however, there are a few differences. The male A. speiseri bears a large tergo-pleural muscle in its mesothorax that is absent in its metathorax and completely lacking in the female, while both sexes of A. reticulata and N. robustus possess the muscle in both segments of their pterothorax. Like H. n. vicinus, A. speiseri has single basalar and subalar muscles while A. reticulata has three basalars and two subalars. However, in A. speiseri, the muscles only occur in the mesothorax. The tergo-trochanteral muscle is large in A. speiseri while it is very small in N. robustus and of moderate size in A. reticulata. The abdominal musculature closely resembles that of Neoconocephalus exiliscanorus (Davis) and Ceuthophilus lapidicola Burm., with only minor exceptions. The alimentary canal resembles that of Amblycorypha rotundifolia (Scudder) and Neoconocephalus ensiger Harris, while the dorsal blood vessel is similar to that reported for Eugaster spinulosus Johnnson;The respiratory system closely resembles that of Phasgonura viridissima L., with one major exception. Whereas in A. speiseri, the wing tracheae are much reduced due to its apterus nature, P. viridissima bears a full complement of wing tracheae with complex basal connections. The nervous system is similar to that described for Conocephalus fasciatus De Geer, except that in A. speiseri the ocelli are absent and the optic lobes are linked to the protocerebrum by long thick stalks. The internal reproductive organs of the female are simple and generalized. In the male, these structures are similar to those of Orchelimum minor Brunner, although in the latter, the epididymis-like convolutions of the vas deferens occur a short distance from the testis. In A. speiseri, the epididymis-like convolutions are located immediately behind the testis.

DOI

https://doi.org/10.31274/rtd-180813-8703

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/

Copyright Owner

Keith Japhet Mbata

Language

en

Proquest ID

AAI8604495

File Format

application/pdf

File Size

240 pages

Included in

Entomology Commons

Share

COinS