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Observations on the Simulium neavei complex at Amani in Tanganyika.*

Published online by Cambridge University Press:  10 July 2009

D. J. Lewis
Affiliation:
Scientific Staff, Medical Research Council, London.

Extract

The paper deals with two members of the Simulium neavi Eoub. complex found at Amani in the forest of the Usambara Mountains, Tanganyika Territory. They have already been described but are at present termed the Amani unhanded and banded forms, scientific names being witheld until the taxonomy of the whole complex is better understood.

Some methods of study are described.

Pupae of the unhanded form constituted a large proportion of the total number found on the common local crab, Potamon (Potamonautes) lirrangensis Eathbun, which amounted to roughly one pupa to seven crabs. This form predominated in the lower and more open parts of the drainage system examined. The adults were not seen to bite man. This and the banded form were found at a much lower altitude than any hitherto reported for the complex, probably owing to the particular nature of the local climate. Neither form was abundant.

The larvae and pupae of the banded form, like the unhanded one, live externally on the crabs. The variability of wing size of the banded form is described. Observations were made on the internal anatomy of the adult with special reference to the ovaries in which the follicular relics are usually very large, indicating that the female probably bites soon after laying eggs. As in S. damnosum Theo. there is an easily recognisable class of old flies with clear Malpighian tubes. Nulliparous and parous flies have rather different biting cycles. The banded form bit man readily but only about five were taken per hour in good catching places and far fewer elsewhere.

Human onchorcerciasis has been reported from Amani but is not known to do any harm there. The existence of the disease in the presence of rather small numbers of Simuliids is of interest in relation to a belief that S. neavei is a more efficient vector of onchocerciasis than is S. damnosum. Out of 359 banded females dissected 41·2 per cent, were parous and 12·8 per cent, of these were infected with nematodes, at least some of which were not Onchocerca volvulus.

Taxonomy, the ovarioles and the Simuliid-crab association are discussed. The formation of the large follicular relics of the banded form is considered in relation to the history of the follicular epithelium before and after ovulation. The crab association is regarded as commensalism-, and it is suggested that the crabs benefit the Simuliids by carrying them a short distance to a suitable current and that they thus enable them to live in fast rivers and so extend their range.

Type
Research Paper
Copyright
Copyright © Cambridge University Press 1960

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References

Abbott, J. F. (1912). An unusual symbiotic relation between a water bug and a crayfish.—Amer. Nat. 46 pp. 553556.CrossRefGoogle Scholar
Allee, W. C., Emerson, A. E., Park, O., Park, T. & Schmidt, K. P. (1949). Principles of animal ecology.—837 pp. Philadelphia, Pa., Saunders.Google Scholar
Allee, W. C. & Schmidt, K. P. (1951). Ecological animal geography.—2nd edn., 715 pp. New York, Wiley.Google Scholar
Baer, J. G. (1951). Ecology of animal parasites.—224 pp. Urbana, Ill., Univ. Ill. Pr.Google Scholar
Barnley, G. R. (1958). Control of Simulium vectors of onchocerciasis in Uganda.—Proc. 10th int. Congr. Ent. 3 535537.Google Scholar
Barnley, G. R. & Prentice, M. A. (1958). Simulium neavei in Uganda.—E. Afr. med. J. 35 pp. 475485.Google Scholar
Bertram, D. S. (1959). The ovary and ovarioles of mosquitos.—W.H.O./Mal./238 pp. 170186, multigraph.Google Scholar
Bonhag, P. F. (1958). Ovarian structure and vitellogenesis in insects.—Annu. Rev. Ent. 3 pp. 137160.CrossRefGoogle Scholar
Chant, D. A. (1957). Descriptions of two new Phytoseiid genera (Acarina: Phytoseiidae), with a note on Phytoseius Ribaga, 1902.—Canad. Ent. 89 pp. 357363.CrossRefGoogle Scholar
Clay, T. & Meinertzhagen, R. (1943). The relationship between Mallophaga and Hippoboscid flies.—Parasitology 35 pp. 1116.CrossRefGoogle Scholar
De Meillon, B. (1957). Bionomics of the vectors of onchocerciasis in the Ethiopian geographical region.—Bull. World Hlth Org. 16 pp. 509522.Google ScholarPubMed
Detinova, T. S. (1944). The relationship between the size of female Anopheles maculipennis atroparvus Thiel and the stage of development of the ovaries on emergence.—Med. Parasit. 13 pp. 5255.Google Scholar
Detinova, T. S. (1959). Course in advanced entomological techniques applied to malaria eradication.—W.H.O./Mal./238 pp. 5169, multigraph.Google Scholar
Detinova, T. S. & Bel'Tyukova, K. N. (1958). On the number of gonotrophic cycles in black flies (Simuliidae) near Krasnoyarsk (Siberia). [In Russian with English summary.]Med. Parasit. 27 pp. 686688.Google Scholar
Dolmatova, A. V. (1942). The life-cycle of Phlebotomus papatasi (Scopoli). [In Russian.]Med. Parasit. 11 no. 3 pp. 5270.Google Scholar
Freeman, P. (1957). The problem of the Simulium neavei complex.—Bull. World Hlth Org. 16 pp. 669670.Google ScholarPubMed
Freeman, P. & De Meillon, B. (1953). Simuliidae of the Ethiopian region.—224 pp. London, Brit. Mus. (Nat. Hist.).Google Scholar
Gabathuler, M. J. & Gabathuler, A. W. (1947). Report of onchocerciasis in the Ulanga District (Eastern Province, T.T.).—E. Afr. med. J. 24 pp. 188195.Google Scholar
Giglioli, M. E. C. (1959). Observations on the structure of the ovariole and the follicular residue body or corpus luteum in Anopheles gambiae.—Trans. R. Soc. trop. Med. Hyg. 53 pp. 310311.Google Scholar
Gillies, M. T. (1954)a. The recognition of age-groups within populations of Anopheles gambiae by the pre-gravid rate and the sporozoite rate.—Ann. trop. Med. Parasit. 48 pp. 5874.CrossRefGoogle ScholarPubMed
Gillies, M. T. (1958a). A modified technique for the age-grading of populations of Anopheles gambiae.—Ann. trop. Med. Parasit. 52 pp. 261273.CrossRefGoogle ScholarPubMed
Gillies, M. T. (1958b). A review of some recent Russian publications on the technique of age determination in Anopheles.—Trop. Dis. Bull. 55 pp. 713721.Google ScholarPubMed
Goiny, H., Van Someren, E. C. C. & Heisch, R. B. (1957). The eggs of Aëdes (Skusea) pembaensis Theobald discovered on crabs.—E. Afr. med. J. 34 pp. 12.Google Scholar
Grenier, P. & Mouchet, J. (1958). Premières captures, au Cameroun, d'une Simulie du complexe neavei sur des crabes de rivières et de Simulium berneri Freeman sur des larves d'Ephémères. Remarques sur la signification biologique de ces associations.—Bull. Soc. Path. exot. 51 pp. 968980.Google Scholar
Henderson, I. F. & Henderson, W. D. (1949). A dictionary of scientific terms.—4th edn.Edinburgh, Oliver & Boyd.Google Scholar
Hesse, R. & Doflein, F. (1943). Das Tier als Glied des Naturganzen.—Tierbau u. Tierleben 2, 828 pp. Jena, Fischer.Google Scholar
Hungerford, H. B. (1919). The biology and ecology of aquatic and semiaquatic Hemiptera.—Kans. Univ. Sci. Bull. 11 pp. 3265.Google Scholar
Hungerford, H. B. (1948). The Corixidae of the Western Hemisphere.—Kans. Univ. Sci. Bull. 32 pp. 1827.Google Scholar
Jordan, P. (1956). Filariasis in the Eastern, Tanga and Northern Provinces of Tanganyika.—E. Afr. med. J. 33 pp. 225233.Google ScholarPubMed
Jordan, P. (1959). A note on the effect of a blood meal on infective larvae of Wuchereria bancrofti in Culex fatigans.—Trans. R. Soc. trop. Med. Hyg. 53 pp. 148150.CrossRefGoogle ScholarPubMed
Kemp, J. F. (1957). The Leon tube: an instrument for measuring flow speeds in water.—J. sci. Instrum. 34 pp. 390392.CrossRefGoogle Scholar
Kozulina, O. V. (1957). On the morphology and biology of Pediculus humanus corporis De Geer (Anoplura, Pediculidae). [In Russian with English summary.]Rev. Ent. URSS 36 pp. 577597.Google Scholar
Lebied, B. (1959). Détermination de l'age physiologique des Diptères …Riv. Parassit. 20 pp. 91106.Google Scholar
Lewis, D. J. (1956). The medical entomology of the Tonkolili Valley, Sierra Leone.—Ann. trop. Med. Parasit. 50 pp. 299313.CrossRefGoogle ScholarPubMed
Lewis, D. J. (1958a). Observations on Simulium damnosum Theobald at Lokoja in Northern Nigeria.—Ann. trop. Med. Parasit. 52 pp. 216231.CrossRefGoogle ScholarPubMed
Lewis, D. J. (1958b). The recognition of nulliparous and parous Anopheles gambiae by examining the ovarioles.—Trans. R. Soc. trop. Med. Hyg. 52 pp. 456461.CrossRefGoogle ScholarPubMed
Lewis, D. J. (1959). Some observations on Ceratopogonidae and Simuliidae (Diptera) in Jamaica.—Ann. Mag. nat. Hist. (13) 1, pp. 721732.Google Scholar
Lewis, D. J. (1960). The Simulium neavei complex (Diptera, Simuliidae) at Amani in Tanganyika.—Proc. R. ent. Soc. Lond. (B) 29.Google Scholar
Lewis, D. J. (in press). Notes on Chrysops bicolor Cordier in Tanganyika.—Proc. R. ent. Soc. Lond. (A) 35.Google Scholar
Mcmahon, J. P. (1957). Notes on the Simulium neavei group of Simuliidae with particular reference to S. nyasalandicum and S. woodi.—Bull. ent. Res. 48 pp. 607617.CrossRefGoogle Scholar
Mcmahon, J. P., Highton, R. B. & Goiny, H. (1958). The eradication of Simulium neavei from Kenya.—Bull. World Hlth Org. 19 pp. 75107.Google ScholarPubMed
Mattingly, P. F. (1957). Genetical aspects of the Aëdes aegypti problem. I. Taxonomy and bionomics.—Ann. trop. Med. Parasit. 51 pp. 392408.CrossRefGoogle Scholar
Moreau, R. E. (1933). Pleistocene climatic changes and the distribution of life in East Africa.—J. Ecol. 21 pp. 415435.CrossRefGoogle Scholar
Moreau, R. E. (1935). A synecological study of Usambara, Tanganyika Territory, with particular reference to birds.—J. Ecol. 23 pp. 143CrossRefGoogle Scholar
Nath, V. (1924). Egg-follicle of Culex.—Quart. J. micr. Sci. 69 pp. 152175.Google Scholar
Nicholson, A. J. (1921). The development of the ovary and ovarian egg of a mosquito, Anopheles maculipennis, Meig.—Quart. J. micr. Sci. 65 pp. 395448.Google Scholar
Ovazza, M. (1957). Présence de Simulies du “groupe neavei” au Moyen Congo, Afrique Equatoriale Française.—Bull. Soc. Path. exot. 50 pp. 537539.Google Scholar
Rubtsov, I. A. (1956). Nutrition and facultativity of bloodthirstiness in black-flies. [In Russian with English summary.]Rev. Ent. URSS 35 pp. 731751.Google Scholar
Rubtsov, I. A. (1958). The gonotrophic cycle in blood-sucking black flies (Simuliidae). [In Russian with English summary.]Parazit. Sborn. Zool. Inst. Akad. Nauk SSSR 18 pp. 255282.Google Scholar
Schlottman, L. L. & Bonhag, P. F. (1956). Histology of the ovary of the adult mealworm Tenebrio molitor L. (Coleoptera, Tenebrionidae).—Univ. Calif. Publ. Ent. 11 pp. 351394.Google Scholar
Smith, A. (1958). Outdoor cattle feeding and resting of A. gambiae Giles and A. pharoensis Theo. in the Pare-Taveta area of East Africa.—E. Afr. med. J. 35 pp. 559567.Google Scholar
Welch, P. S. (1948). Limnological methods.—Philadelphia, Pa., Blakiston.Google Scholar
Wigglesworth, V. B. (1949). The physiology of mosquitoes. In Boyd, M. F.Ed. Malariology 1 pp. 284301. Philadelphia, Pa., Saunders.Google Scholar
Wigglesworth, V. B. (1953). The principles of insect physiology.—5th edn., 546 pp. London, Methuen; New York, Dutton.Google Scholar
Woodman, H. M. (1958). Filariasis with special reference to Loa Loa and Onchocerca volvulus.—E. Afr. med. J. 35 pp. 457465.Google Scholar
Yonge, C. M. (1949). The sea shore.—311 pp. London, Collins.Google Scholar