World Congress of Malacology Antwerp ... - Unitas Malacologica

scaling relationship may be the result of squid’s unique body geometry, mode of swimming,, or
circulatory system.
Digital imaging of micro bivalves
Turner, James A.; Oliver, Graham P.
Department of BioSyB, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK,
Email: james.turner@museumwales.ac.uk
The Department of Biodiversity & Systematic Biology (BioSyB) at the National Museum of Wales
has, over recent years, embarked upon a number of projects aimed at producing taxonomic tools to
aid researchers in the identification of bivalves. Digital imaging has been key to many of these
projects. Over three thousand images have been captured in under four years, with many of these
being images of bivalve specimens of 5mm in size or less.
Advancements in digital camera technology, microscope optics and image capture software has
allowed researchers to capture more detailed and higher quality images than ever before.
Digital imaging using light microscopy at high magnifications does, however, have its limitations.
Features that may be diagnostic for species identification can often be difficult to illustrate using this
technique alone, and other methods, such as Scanning Electron Microscopy (SEM) and traditional
line illustration, may be better suited to the task. However, the best results are often achieved by
using a combination of these methods.
Drawing from the experiences gained whilst undertaking digital imaging projects, the presentation
will cover current working practices in place at the National Museum of Wales, providing details on
the equipment and techniques in use. Specimen preparation, lighting methods, digital image postprocessing
and image file management will be discussed. These topics will detail the methods used
for capturing aspects of bivalve morphology of both the shell and the anatomy in order to produce
publication quality images for taxonomic research.
Phylogeography and evolution of the Caribbean land snail family Urocoptidae (Gastropoda,
Pulmonata): radiation in isolation
Uit de Weerd, Dennis
Academy of Natural Sciences, 1900 Benjamin Franklin Parkway, Philadelphia, Pennsylvania 19103,
USA,
Email: uitdeweerd@acnatsci.org
The land snail family Urocoptidae has an extraordinary diversity in the Caribbean area, both in terms
of number of species and in terms of ecological differentiation. On the Greater Antilles, which
harbour the majority of species, there are conchologically distinct ground-dwelling, rock-dwelling
and arboreal forms. Similar shell forms are often found on different islands, a pattern that can be
explained by assuming multiple colonisation events and/or parallelism/convergence. So far biologists
have not been able to assess the role of these processes, for want of a phylogeny based on an
independent set of characters.
In this study such a dataset was assembled, consisting of nuclear (28S) and mitochondrial (COI)
DNA sequences of representatives of most genera within the Urocoptidae. Phylogenetic analyses of
these data overturn the current morphology-based classification within the family, and instead
support several clades confined to (palaeo)islands. These clades unite morphologically dissimilar
forms, indicating independent radiations. Similar ecological specialisations evolved independently on
different islands. With a few exceptions, dispersal between islands has been rare. Besides shedding
light on the phylogeography and evolution of the Urocoptidae, this study has implications for
taxonomy and conservation.
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