Date Awarded

1992

Document Type

Dissertation

Degree Name

Doctor of Philosophy (Ph.D.)

Department

Virginia Institute of Marine Science

Advisor

John A. Musick

Committee Member

David Johnson

Abstract

Morphology is described for larvae of Diploprion bifasciatus, Belonoperca chabanaudi, Jeboehlkia gladifer, and Grammistes sexlineatus of the serranid subfamily Epinephelinae. Known larvae of all epinephelines are compared. Larval epinephelines differ in patterns of pigmentation, head spination, sequence of fin formation and morphology of elongate (often spectacularly so!) dorsal-fin spines. Relationships among epinepheline genera are investigated based on phylogenetic analysis of larval and adult morphology. Five monophyletic tribes are cladistically delineated, and relationships among tribes and among genera of the tribe Grammistini are hypothesized. Generic composition of tribes differs from Johnson's (1983) classification only in the allocation of Jeboehlkia to the tribe Grammistini rather than the Liopropomini. Despite the presence of the ichthyotoxin grammistin in the Diploprionini and Grammistini, the latter is proposed to be the sister group of the Liopropomini. This hypothesis is based, in part, on previously unrecognized larval features. Larval morphology also provides convincing evidence of monophyly of the subfamily Epinephelinae, the clade comprising all epinepheline tribes except Niphonini, and the tribe Grammistini. Larval features provide the only evidence of a monophyletic Epinephelini and a monophyletic clade comprising the Diploprionini, Liopropomini and Grammistini; identification of larvae of more epinephelines is needed to test those hypotheses. Within the tribe Grammistini, Jeboehlkia gladifer is hypothesized to be the sister group of a natural assemblage comprising the former pseudogrammid genera (Aporops, Pseudogramma and Suttonia). The "soapfishes" (Grammistes, Grammistops, Pogonoperca and Rypticus) are not monophyletic, but form a series of sequential sister groups of Jeboehlkia, Aporops, Pseudogramma and Suttonia (the closest of these being Grammistops, followed by Rypticus, then Grammistes plus Pogonoperca). The absence in adult Jeboehlkia of several derived features shared by Grammistops, Aporops, Pseudogramma and Suttonia is incongruous with this hypothesis but may be attributable to paedomorphosis. The generic phylogeny of the Grammistini proposed herein emerges as the single most parsimonious hypothesis largely because of the method chosen for analyzing multistate characters. This study demonstrates that ontogeny is valuable in phylogenetic studies as a source of characters, means of assessing homology and aid to identifying heterochrony.

DOI

https://dx.doi.org/doi:10.25773/v5-efmt-s879

Rights

© The Author

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