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The postembryonic development of fish copepod (Caligoida, Lernaeoceriformes) in pelagic snails (Janthina spp.)Ho, Ju-Shey January 1965 (has links)
Thesis (M.A.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / In all, 7587 copepods were recovered from 115 pelagic snails of two species, Janthina janthina (Linnaeus) and J. globosa Swainson, which had been collected from the West Indies,and Madagascar. They were found either free inside the mantle cavities or fixed on to the gill lamellae of the snails, and represent a complete series of the postembryonic developmental stages of a lernaeoceriform copepod.
Five stages were recognized. They are:
1. Free-swimming copepodid: 0.42-0.48 mm.
The body has an oblong cephalothorax and four free segments.
There are two pairs of well-developed biramous legs. The third pair is represented merely by a pair of spines on the second free segment. The third free segment represents the fourth thoracic segment and carries no legs. The last free segment carries a pair of caudal rami which bear 4 plumose setae and one short setule. The first antenna is indistinctly 4-segmented, with the formula 1, 1, 1, and 11 plus one aesthete; the two long setae on the terminal segment are bifurcate. The second antenna is 3-segmented, chelate and powerful. The mouth tube is of the usual form found in lernaeoceriform copepods, There is, however, a pair of spatulate labial palps which have not been described before in any known lernaeoceriform copepodids. The mandible is lanceolate, without teeth. The first maxilla is bipartite: a small exopod armed with a single seta and a large endopod tipped with two stout setae. The second maxilla is 3-segmented, with a falciform terminal segment bearing striations. Each ramus of the first two pairs of legs is 1-segmented; the first exopod: III,I,3; the first endopod: 7; the second exopod: II,I,3; and the second endopod: 6 [TRUNCATED]. / 2031-01-01
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Porovnání embryonálního vývoje původních a nepůvodních druhů raků / Comparison of embryonic Development of Native and Non-native CrayfishKOUBA, Antonín January 2007 (has links)
The embryonic and early postembryonic development of all crayfish occurring open water of the Czech Republic were studied under controlled conditions.
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Vývoj a růst bentické vodní ploštice hlubenky skryté(Aphelocheirus aestivalis(Fabricius,1794)(Insecta: Heteroptera: Aphelocheiridae) / Morphogenesis and growth of the benthic water bug (\kur{Aphelocheirus aestivalis }(Fabricius, 1794) (Insecta: Heteroptera: Aphelocheiridae).INDROVÁ, Eliška January 2008 (has links)
INDROVÁ E. 2008: Development and growth of the benthic water bug (Aphelocheirus aestivalis (Fabricius, 1794) (Insecta: Heteroptera: Aphelocheiridae). MSc. Thesis, University of South Bohemia, Pedagogical Faculty, České Budějovice. 62 pp. Postembryonic morphogenesis of the benthic water bug (A. aestivalis) was studied. Morphometric characters were measured in specimens of population from the Dračice River (South Bohemia: Třeboňsko). Differential characters of individual developmental stages are described and illustrated. Growth of this species is characterised by diagrams and equations of selected body parametres.
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Růst a vývoj hmyzích křídel v průběhu ontogeneze se zřetelem na skupinu Palaeodictyoptera / The growth and development of wings during ontogeny with emphasis on PalaeodictyopteraRosová, Kateřina January 2020 (has links)
The series of two fossil species belonging to the order Palaeodictyoptera from the Late Carboniferous of Kuznetsk Basin in Russia were re-examined. The two species as Tchirkovaea guttata and Paimbia fenestrata were investigated with emphasis on the wing growth and development in comparison with the structure of developing wings in recent mayflies. This fossil material of T. guttata and P. fenestrata was long considered by previous authors as undisputed evidence for a unique type of wing development in the Palaeozoic insects. The idea was that the larvae of these insects possessed the wings, which became articulated and fully movable already earlier during the postembryonic development and that these gradually growing wings changed their position from longitudinal to perpendicular to the body axis. Moreover, the development was supposed to include two or more subimaginal instars, implying that the fully winged instars moulted several times during postembryonic development. After detailed study of the available fossils and subsequent comparison of the fossil evidence with the development of wings in the recent mayfly Cloeon dipterum it was discovered, that the alleged series of immature, subimaginal and imaginal wings of T. guttata and P. fenestrata do not provide clear evidence that would support...
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