World Congress of Malacology Antwerp ... - Unitas Malacologica

Phylogeny of Aeolidacea (Gastropoda: Nudibranchia)
Alejandrino, Alvin
Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California
90007, USA,
Email: aalejandrino@nhm.org
Aeolidacea is one of four diverse clades of nudibranch gastropods. However, for more than 200 years
since its description, only a handful of phylogenetic studies have been conducted, which focused on
genera and species level relationships. The majority of these studies used morphology data, while one
recent study used molecular information. Morphology characters and mitochondrial fragments 16s
and Cytochrome Oxidase I (COI) genes were used in this study to determine the monophyly of
Aeolidacea. A morphology data matrix was constructed from 60 species using 75 characters. The
mitochondrial genes of thirty-six species were sequenced and combined with sequences available
online. Morphology and molecular phylogenetic relationships were acquired using PAUP* for
maximum parsimony. Maximum likelihood and Mr. Bayes analyses were also applied for the
molecular data. Support for nodes on parsimony and likelihood trees were calculated using Bootstrap
analysis in PAUP*. All molecular phylogenetic trees do not support the monophyly of Aeolidacea
because several Dendronotacea genera (Hancockia, Doto, Dendronotus, Scyllaea, and Tethys) form a
clade sister to Fionoidea. Embletonia gracilis and Pseudovermis sp. were consistently basal to all the
other Aeolidacea as well as other Dendronotacea species (Marionia sp.). Fiona pinnata and Calma
glaucoides consistently fell within the Eubranchidae/Tergipedidae clade, suggesting a need for
reclassification of their respective families. This study provides a base for further analysis on lower
and higher-level taxonomy, helping to resolve issues relating to the monophyly of genera as well as
Cladobranchia, Nudibranchia, and Opisthobranchia.
Active camouflage in a snail
Allgaier, Christoph
Department of Zoology, Division of Evolutionary Biology of Invertebrates, Eberhard Karls
University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany,
Email: christoph.allgaier@uni-tuebingen.de
The shells of some pulmonate species in a diverse array of families carry extraneous layers, mostly
consisting of dust or soil. In most cases, the manner in which such layers are positioned onto the shell
remains unknown. Napaeus barquini (Pulmonata, Enidae) from the Canary island of La Gomera,
exhibits an impressive extraneous layer which is arranged in the form of prominent lichen
protuberances on the shell. Some of these protuberances may even extend beyond the tip of the shell.
The way that these lichens are positioned onto the shell and the manner in which they adhere were
investigated. The snail grazes lichen material from the substrate and applies it to the surface of its
shell in a standardized pattern of movements. The snail uses its mouth to place the moist material
onto the shell and to form it into protuberances that adhere as they dry out. To do this, Napaeus
barquini extends its body far beyond the shell margin so that it can reach the entire outer surface of
the shell and cover it with protuberances, presumably as camouflage.
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