Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-08T08:25:15.828Z Has data issue: false hasContentIssue false
  • English
  • Français

The structure and possible function of the signum of Glossina tabaniformis Westwood

Published online by Cambridge University Press:  06 April 2009

A. M. Jordan
A. M. Jordan
Affiliation:
West African Institute for Trypanosomiasis Research, Kaduna, Northern Nigeria
Get access Rights & Permissions [Opens in a new window]

Extract

1. In all species of the fusca group of tsetse flies (Glossina), except G. brevipalpis Newstead, a gelatinous structure, the genital fossa, is present at the anterior end of the uterus. On the surface of the genital fossa is a toughened structure known as the signum.

2. Probably chitin and certainly calcium are present in the substance of the signum of G. tabaniformis Westwood. An opaque concretion develops on the signum after the female has been fertilized. The concretions may be caused by a reaction between sperms or secretions from the male accessory glands and materials in the substance of the genital fossa; the possibility that the concretions are ‘mating scars’ produced by pressure of the harpes of the male on the signum is considered unlikely. Concretions are not present on the signa of all species.

3. A possible mechanism of fertilization in G. tabaniformis is discussed, and it is suggested that the signum may act as a protective shield for the anterior part of the uterus and common oviduct of the female from the harpes of the male which are inserted into the uterus during coitus. The views of Machado (1959) are discussed and it is agreed that the signum probably acts as a protective shield in all species in which it occurs and differences in the form of the signum between species may be related to differences in the form of the harpes of the male.

I wish to thank Dr J. Williamson for chromatography, Dr L. E. Stephen and Mr K. E. Broomfield for advice and assistance with the sectioning of the signa, Dr F. Peers for operating the Flame Photometer, Dr D. G. Godfrey for suggesting that the signa should be examined for calcium, and Mr W. Petana for taking the photomicrographs.

I am indebted to Dr K. C. Willett, Director of the West African Institute for Trypanosomiasis Research, for criticism of the manuscript.

Type
Research Article
Information
Parasitology , Volume 53 , Issue 1-2 , May 1963 , pp. 145 - 153
Copyright
Copyright © Cambridge University Press 1963

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Campbell, F. L. (1929). The detection and estimation of insect chitin; and the interrelation of chitinization to hardness and pigmentation of the cuticle of the American cockroach, Periplaneta americana L. Ann. Ent. Soc. Amer. 22, 401–26.CrossRefGoogle Scholar
Carleton, H. M. & Drury, R. A. B. (1957). Histological Technique. Oxford.Google Scholar
Gillies, M. T. (1956). A new character for the recognition of nulliparous females of Anopheles gambiae. Bull. World. Hlth Org. 15, 451–9.Google ScholarPubMed
Henrard, C. (1952). Une tsé-tsé nouvelle du groupe ‘fusca’, Glossina vanhoofi, sp.nov. Rev. Zool. Bot. Afr. 45, 193–7.Google Scholar
Jordan, A. M. (1958). The mating behaviour of females of Glossina palpalis (R.-D.) in captivity. Bull. Ent. Res. 49, 35–43.CrossRefGoogle Scholar
Jordan, A. M. (1962). The ecology of the fusea group of tsetse flies (Glossina) in southern Nigeria. Bull. Ent. Res. 53, 355–85.CrossRefGoogle Scholar
Kossa, von (1901). Beitr. path. Anat. 29, 163.Google Scholar
Machado, A. de Barros (1959). Nouvelles contributions à l'étude systématique et biogéographique des Glossines (Diptera). Publ. cult. Co. Diam. Angola, 46, 13–90.Google Scholar
Mellanby, K. (1936). Experimental work with the tsetse-fly, Glossina palpalis, in Uganda. Bull. Ent. Res. 27, 611–32.CrossRefGoogle Scholar
Nash, T. A. M. & Jordan, A. M. (1959). A guide to the identification of the West African species of the fusca group of tsetse-flies, by dissection of the genitalia. Ann. Trop. Med. Parasit. 53, 72–88.CrossRefGoogle Scholar
Newstead, R., Evans, A. M. & Potts, W. H. (1924). Guide to the study of tsetse-flies. Mem. L'pool. Sch. Trop. Med., N.S., no. 1.Google Scholar
Patton, W. S. (1936). Studies on the higher Diptera of medical and veterinary importance: a revision of the species of the genus Glossina Wiedemann based on a comparative study of the male and female terminalia. Ann. Trop. Med. Parasit. 30, 71–89.CrossRefGoogle Scholar
Potts, W. H. (1955). A new tsetse-fly from the British Cameroons. Ann. Trop. Med. Parasit. 49, 218–26.CrossRefGoogle ScholarPubMed
Squire, F. A. (1951). Observations on mating scars in Glossina palpalis (R.-D.). Bull. Ent. Res. 42, 601–4.CrossRefGoogle Scholar
Vanderplank, F. L. (1948). Experiments in cross-breeding tsetse-flies (Glossina species). Ann. Trop. Med. Parasit. 42, 131–52.CrossRefGoogle Scholar
Vaucel, M. (1943). Glossines du Cameroun Français. Rev. Sci. Méd. pharm. Vét. Afr. jr. libre, Brazzaville 2, (2), 97–100.Google Scholar
Wiesmann, R. (1938). Untersuchungen über die Struktur der Kutikula des Puppentönnchens der Kirschfliege, Rhagoletis cerasi L. Vjschr. naturf. Ges. Zurich, 83, 127–36.Google Scholar