1999. 7 (1)


About authors:

A.B. Lange , Department of Entomology; Faculty of Biology, Moscow Lomonosov State University, Moscow, 119992 Russia
Tolstikov A.V., Tyumen State University, Department of Zoology and Evolutionary Ecology of Animals, 10 Semakova str., Tyumen, 625003 Russia


The peculiarit ies of formation of the prelarva, as well as the eclosion process in hydrophilous oribatid mites Trhypochthoniellus setosus (Willmann, 1928) and Hydrozetes lemnae (Coggi, 1899) were described as a result of observations on the embry - ogenesis in vivo. The prelarvae of species studied are immotile and fetal. They belong to two known types according to the classification of Lange, 1960: in prelarvae of T.setosus the appendages are represented by sheathlike structures, whereas those appendages in H.lemnae are not morphologically developed. The prelarva of H.lemnae has a sack-like form as many higher Acariformes. The ontogeny of mentioned species is accompanied by the lecital andtheuteralembryonization [Lange, 1960; Lange, Sokolova, 1992], but at different degrees. In H.lemnae the eggs are deposited at the early phases of embryogenesis, whilst in T.setosus the process of the embryonization goes further, and the eggs are deposited with the larva ready to eclose (ovoviviparity). The eclosion of T.setosus goes in two steps: the partial eclosion ("semieclosion") of the prelarva, and the final eclosion of the larva. It is found that the frontal peak of the prelarva functions as the "egg tooth". In H.lemnae the prelarva does not tear the egg coverings, and the larva is the eclosion stage.

The development of studied species of mites demonstrates different degrees of both the lecital and the uteral embryonizations with their most derived state in T.setosus where it includes the embryogenesis, the prelarva and the formation of the larva,


Baker J.T. 1985. Feeding, moulting and the internal anatomy of Hydrozetes sp. (Oribatida: Hydrozetidae) // Zool. Jb. Anat. Bd.l 13. S.77-83.

Bottger К. 1977. The general life cycle of fresh water mites (Hydrachnellae, Acari) // Acarologia. T.18. Fasc.3. P.496-502.

Coineau Y. 1977. La premiere prelarve elattostatique connue chez les Acariens // Acarologia. T. 19. Fase. 1. P.46-54.

Coineau Y. 1979. LesAdamystidae, uneetonnantefamille d'acariens prostigmates primitifs // E.Piffl (ed.): Proceed, of the 4th Int. Congr. Acarology. Akademai Kiado, Budapest. P.431-435.

Evans G.O. 1992. Principles of Acarology / CAB Inter-national, Wallingford, U.K. 563 pp.
Fain A., Herin A. 1978. La prelarve chez les Astigmat.es (Acari) // Acarologia. T.20. Fasc.4. P.566-571.

Grandjean F. 1948. Sur le Hydrozetes (Acariens) de l'Europe occidentale // Bull. Mus. Nat. Hist. Na-turelle. T.20. Fasc.4. P.328-335.

Grandjean F. 1962. Prelarves d'Oribates // Acarologia. T.4. Fasc.3. P.423-439.

Herfs A. 1926. Òkologisches untersuchungen an Pedicu-loides ventricosus (Newp.) Beri. // Zoologica. Bd.74. S. 1-68.

Ivanov P.P. (Iwanoff P.P.) 1928. Die Entwicklung der Larvalsegmente bei den Anneliden / / Zschr. Morph. Oekol. Tiere. Bd.10. S.62-161.

Kethley J.B. 1991. Calyptostasic nymphs of Neona-norchestes (Nanorchestidae): a third example of alternating calyptostasy / / Dusbabek F., Bukva V. (eds): Modern Acarology. Academia, Prague and SPB Pubi., The Hague. Vol.2. P.279-282.

Lange A.B. 1957. [On the nature of six-legged larvae of mites] // II Sovezhanie embriologov U.S.S.R. Abstracts. Moscow. S.97-99. [In Russian]

Lange A.B. 1960. [Prelarva of mites of the ordo Acari-formes and its peculiarities in Palaeacarida (Palae-acariformes)] // Zoologichesky Zhurnal. T.39. №12. S. 1819-1824. [In Russian]

Lange A.B. 1964. [Embryonic development of lower mites] // I Nauchnaya Otchetnaya Konferenciya M.S.U. Biology and Soil Faculty. Abstracts. MSU, Moscow. S.87-88. [In Russian]

Lange A.B. 1966a. [On the origin of mite-like Chelicer-ata] // I Acarologicheskoye Sovezhanie. Abstracts. Nauka, Moscow. S. 120-121. [In Russian]

Lange A.B. 1966b. [Embryonic development of lower Acariformes and some problems of the evolution of Chelicerata] // I Acarologicheskoye Sovezhanie. Abstracts. Nauka, Moscow. S. 121 -122. [In Russian]

Lange A.B. 1970. [Morpho-trophic relations and the evolution of ontogenesis of invertebrates] // III Konferenciya po problemam "Temp Individualnogo razvitiya zhivotnykh". USSR Institut Evolution-noy Morphologii i Ecologii zhivotnykh, Moscow. S.24-25. [In Russian]

Lange A.B. 1976. [Miniaturization as an evolutionary nature of mitelike arthropods] // III Vsesoyuznaya Konferenciya po teoreticheskoy i prikladnoy ac-arologii. Tashkent. S. 156-157. [In Russian]

Lange A.B. 1996. [Invertebrates. In vivo study of the embryonic development of invertebrates in a sus-pended water drop and principles of descriptive morphology] // Metody embryologicheskikli issle-dovaniy. V.A. Golichenkov (ed.), M.S.U., Moscow. S. 108-132. [In Russian]

Lange A.B., Sokolova T.V. 1992. [Uterine larvae of mange mites Sarcoptes scabiei (L.) (Sarcoptidae) and the ontogenetic level of the eclosing progeny in mites of the ordo Acariformes] // Biologicheskiye Nauki. T.5. S.63-71. [In Russian]

Michael A.D. 1884.  British  Oribatidae  / Vol.l. Ray Society, London. 336 pp.

Norton R.A. 1994. Evolutionary aspects of oribatid mite life-histories, and consequences for the origin of the Astigmata // M.A.Houck (ed.) Mites: Ecological and Evolutionary Analyses of Life-History Patterns. Chapman and Hall, New York. P.99-135.

Norton R.A., Kethley J.B. 1994. Ecdysial cleavage lines of acariform mites (Arachnida: Acari) // Zool. Scripta. Vol.23. No.3. P. 175-191.

Otto J.C. 1997. Observations on prelarvae in Anystidae and Teneriffiidae // Mitchell R.D., Horn D.J., Needham G.R., Welbourn W.C. (eds): Acarology IX. Proceed, of the 9th Int. Congr. Acarology. Columbus, Ohio. P.343-354.

Otto J.C., Olomski R. 1994. Observations on a motile prelarva in Chaussieria venustissima (Berlese, 1882) (Acari: Anystidae) with a description of the larva // Can. J. Zool. T.72. P.287-292.

Palmer S., Norton R.A. 1991. Taxonomic, geographic and seasonal distribution of thelytokous partheno-genesis in the Desmonomata (Acari: Oribatida) // Experimental and Applied Acarology. V. 12. P.67-81.

Shatrov A.B. 1998. [Prelarvae of mites of the superfamily Trombidioidea (Acariformes)] // Entomologicheskoye Obozreniye. T.77. Vyp.4. S.923-936. [In Russian]

Sokolova T.V.,  Fedorovskaya  R.F.,  Lange A.B.  1989. Scabiosis / Medicina, Moscow. 175 ss. Iln Russian] Schuster R., Potsch H. 1989. Another record of an active prelarva in mites / G.P.Channabasavanna, C.A.Vira-ktamath (eds): Progress in Acarology. Vol.l. Oxford and IBH Publishing Co., New Dehli. P.261-265.

Taberly G. 1952. Sur l'ethologie et le developpement postembryonnaire de Trhypochthonius tectorum // Bull. Soc. Zool. France. T.77. P.330-341.

Tolstikov A.V. 1996. Acariformes. Eleutherengona. Oribatida. Astigmata // S.Ya. Tsalolikhin (ed.) Opredelitel presnovodnykh bespozvonochnykh Rossii b prilezhazhikh stran. Nauka, St. Peters-burg. S . 9 - 12, 49 - 60, 66 - 67, 135-147. [In Rus-sian]

Tolstikov A.V., Petrova A.D. 1996. [To the problem of the transition of acariform mites into freshwaters] // Problemy Pochvennoy Zoologii. I Vserossiyskaya Konferentsiya po pochvennoy zoologii. Abstracts. Rostov-on-Don. S.170-172 [In Russian]

Tolstikov A.V., Petrova A.D. 1997. [Manual to Collect-ing and Identification of Acariform Mites of the Continental Freshwater Bodies. Part 1] / Tyumen State Univ., Tyumen. 19 s. [In Russian]

Zakhvatkin A.A. 1949. [Comparative Embryology of Lower Invertebrates] / Sovetskaya Nauka, Moscow, 395 s. [In Russian]

Zakhvatkin A.A. 1953a. [Researches on the Morphology and the Postembryonic Development of Tyro-glyphoidea (Sarcoptiformes, Tyroglyphoidea)] // Zakhvatkin A.A. Collection of Scientific Papers. Moscow State Univ., Moscow. S. 19-120. [In Russian]

Zakhvatkin A.A. 1953b. [Conspectus of the Course "Em-bryology of Arthropoda"] // Zakhvatkin A.A. Col-lection of Scientific Papers. Moscow State Univ., Moscow. S.335-375. [In Russian]

Zakhvatkin A.A., Lange A.B. 1953. [Conspectus of the Course "Acarology"] // Zakhvatkin A.A. Collection of Scientific Papers. Moscow State Univ., Moscow. S.285-334. [In Russian]