Journal of the Marine Biological Association of the United Kingdom

Research Article

The gastrotrich community of a north Adriatic Sea site, with a redescription of Musellifer profundus (Chaetonotida: Muselliferidae)

F. Leasia1 and M.A. Todaroa2 c1

a1 Dipartimento di Biologia, Università di Milano, via Celoria 26, I-20133 Milano, Italy

a2 Dipartimento di Biologia Animale, Università di Modena e Reggio Emilia, via Campi 213/d, I-41100 Modena, Italy

Abstract

During a survey of the marine meiobenthos in a predominantly muddy area, 40 km south of Venice (northern Adriatic Sea, Italy), 11 species of gastrotrichs were recorded. Gastrotrichs were found in 11 out of the 16 investigated stations, with densities (mean ± standard deviation) ranging from 0.6 ± 0.5 to 97.7 ± 71.2 ind./10 cm2. The community was dominated by Musellifer profundus, which made up 24.5% of the entire gastrotrich assemblage and reached in a single station the abundance peak of 18.3 ind./10 cm2. The finding bears relevance to the biogeography and ecology of several species. The presence of numerous specimens of the rare M. profundus allowed new insights into the arrangement and functioning of the hermaphroditic sexual apparatus in this phylogenetically important genus, for which such data are scanty. The new information will certainly be useful in evolutionary studies aimed at reconstructing the phylogenetic relationships within Gastrotricha, while offering at the same time additional morphological traits to be used in reliable species identification. Although only three species of Musellifer have been described so far, there are several others awaiting a formal affiliation, a task that will benefit from this new information.

(Received June 17 2009)

(Accepted July 24 2009)

(Online publication October 21 2009)

Correspondence:

c1 Correspondence should be addressed to: M.A. Todaro, Dipartimento di Biologia Animale, Università di Modena e Reggio Emilia, via Campi 213/d, I-41100 Modena, Italy email: antonio.todaro@unimore.it