Please use this identifier to cite or link to this item:
|Title:||Biology and ontogeny of cretaceous and recent cyprididae ostracoda (crustacea)|
|Authors:||Smith, Robin James.|
|Presented at:||University of Leicester|
|Abstract:||Study of the biology and ontogeny of Cretaceous and Recent ostracods shows that the family Cyprididae exhibits conservative evolution over the last 100 million years. The Cretaceous cypridid ostracod Pattersoncypris micropapillosa Bate, 1972, with preserved appendages, is described and details of the limbs of its adults and juveniles are compared with Recent Cyprididae.;A detailed study of the ontogeny of the Recent Cyprididae ostracod Eucypris virens Jurine, 1820) reveals that, with the exception of the last podomere on the antennules, the chaetotaxy (distribution pattern of setae) shows continual development on all podomeres of the limbs. Cyprididae ostracods have a pediform limb in the posterior part of the body, presumably to help them to attach to substrates; this is reflected by the pediform nature of one limb in all ontogenetic stages. This study has also shown that the fifth limb is more probably of thoracic origin and, hence, ostracods have only one pair of maxillae.;The upper lip and hypostomes of 23 species of Cypridoidea (Podocopina) ostracods were studied and significant variation noted in morphology between species, genera and subfamilies. Several features of the upper lip and hypostome are described for the first time. The morphology of the upper lip can be used to identify species, but it cannot be used to diagnose genera or subfamilies.;Spherical objects recovered from acetic acid preparation residues of vertebrate fossils from the Lower Cretaceous Santana Formation of north-east Brazil are postulated to be the eggs of the ostracod Pattersoncypris micropapillosa Bate, 1972. These spheres are phosphatized, range in diameter from 85 to 110 m, and are comparable in many respects to the eggs of several Recent ostracod species.|
|Rights:||Copyright © the author. All rights reserved.|
|Appears in Collections:||Theses, Dept. of Geology|
Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.