Extraordinary morphological changes in valve morphology during the ontogeny of several species of the Australian ostracod genus Bennelongia (Crustacea, Ostracoda)
- Ostracods belonging to the genus Bennelongia differ much in valve morphology between adults and juveniles. Adult valves are asymmetrical, characterised by a beak-like feature in the anteroventral region of the left valve, and, with some notable exceptions, mostly have smooth or weaklyornamented valves. Juvenile specimens, on the other hand, have valves that are almost symmetrical, with no beak-like feature and are often heavily ornamented. We have examined the last 3 - 4 juvenile stages of 6 Bennelongia species from 5 different lineages, in order to decipher the types of external valve ornamentation and their recurrences during ontogeny and across lineages. It is clear that ornamentation is more prevalent at the early instar stages compared to the last 2 pre-adult stages, and especially when compared to the adult stage itself. We also examined the surprising presence of a calcified inner lamella with a prominent inner list in the pre-adult stages of Bennelongia species, that is usually absent in juveniles of other ostracods, thus questioning if heterochronic processes have provided an intermediate valve morphology between the simple (normal) cypridinid juvenile state and the heavily derived and modifi ed state of adult Bennelongia. We discuss the possible (speculative) functionality of the ornamentation in juveniles.
Author: | Patrick De Deckker, Koen Martens |
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URN: | urn:nbn:de:hebis:30:3-327133 |
DOI: | https://doi.org/10.5852/ejt.2013.36 |
Parent Title (English): | European journal of taxonomy : 36 |
Series (Serial Number): | European journal of taxonomy : EJT (36) |
Publisher: | Muséum National d'Histoire Naturelle |
Place of publication: | Paris |
Document Type: | Part of Periodical |
Language: | English |
Date of Publication (online): | 2013/01/31 |
Date of first Publication: | 2013/01/31 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2013/12/18 |
Tag: | Moulting; instar; nodes; pore morphology; setae |
Page Number: | 37 |
First Page: | 1 |
Last Page: | 37 |
HeBIS-PPN: | 363059903 |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 59 Tiere (Zoologie) / 590 Tiere (Zoologie) |
Sammlungen: | Sammlung Biologie / Sondersammelgebiets-Volltexte |
Licence (German): | Creative Commons - Namensnennung 3.0 |