Size polymorphism in Oncaea venusta Philippi, 1843 and the validity of O. frosti Heron, 2002: a commentary

• Published in: Hydrobiologia Vol. 513; no. 1; pp. 1 - 5
• Main Authors: BOTTGER-SCHNACK, Ruth, HUYS, Rony
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01-02-2004; Springer Nature B.V
• Subjects: Biological and medical sciences; Birds; Comparative analysis; Crustacea; Fundamental and applied biological sciences. Psychology; Invertebrates; Morphology. Histology. Cytology; Crustacea; Aquatic environment; Hydrobiology; Arthropoda; Interspecific comparison; Morphology; Body size; Copepoda; Taxonomic character; Invertebrata; Morphometry; Polymorphism
• ISSN: 0018-8158; 1573-5117
• DOI: 10.1023/b:hydr.0000018301.50664.3d

The morphological characters used to describe Oncaea frosti Heron, 2002 (Copepoda, Poecilostomatoida), an Atlantic medium-sized form variant of O. venusta Philippi, 1843, appear to be inadequate in view of the great polymorphism known for this ubiquitous species. Comparative analysis of published and newly collected length data of O. venusta variants worldwide demonstrates that O. frosti cannot be unequivocally delineated in the Indo-West Pacific. The validity of O. venella Farran sensu Heron (2002) is questioned and comments are given on Heron's synonymization of O. venusta f.venella sensu Ferrari (1975) and sensu Böttger-Schnack (2001) with O. frosti. As long as the significance of the morphological characters used to separate O. venusta form variants is not substantiated by data emerging from alternative taxonomic methods, such as the analysis of gene sequences, the species names O. frosti and O. venella Farran sensu Heron (2002) are regarded as species inquirendae in the genus Oncaea.[PUBLICATION ABSTRACT]