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155
DENVER MUSEUM OF NATURE & SCIENCE
REPORTS
|
No. 3, July 2, 2016
right- vs left-handed asymmetries. To date, instraspecific
variation in male form in these bird-associated mites has
received attention only from a taxonomic point of view
with little effort put into determining whether the varia-
tion is truly a distinct polymorphism (vs, e.g., continuous
variation) and whether there are any environmental cor-
relates associated with variation in male morphology. Here
I investigate three distinct examples of variation in male
morphology in bird associated mites: the nest mite
Stur-
nophagoides bakeri
, the pigeon feather mite
Falculifer
rostratus
and the cormorant feather mite
Michaelia
sp. For
the nest mite, there were no clearly distinct morphs, but
rather a continuum of leg and body sizes. For
F. rostratus
,
unlike in
S. berlesei
, there was no relationship between
population density and propensity for expression of the
heteromorphic state. Asymmetry of male
Michaelia
was
strongly correlated with which side of the host bird they
were found on. Future research could address the relation-
ship between male morphology at a finer scale (e.g., per
feather rather than per bird), and how the modified
male structures are actually used by the male mites.
Keywords: sexual selection, male competition, asymmetry
Oral presentation
Uncharted diversity and evolutionary
history of Neotropical samooid harvest-
men (Opiliones: Laniatores: Samooidea)
Daniel N. Proud
1,2
, Abel Pérez-González
2
1
Appalachian State University, Department of
Biology, ASU Box 32027, Boone, NC 28608, USA;
2
Museo Argentino de Ciencias Naturales “Bernardino
Rivadavia” (MACN), División Aracnología, Av. Angel
Gallardo 470, C1405DJR Buenos Aires, Argentina
dnp0646@gmail.comThe superfamily Samooidea is a diverse group of lania-
torean harvestmen comprised of 212 species that were,
until this work, divided into three families: Biantidae,
Samoidae, and Stygnommatidae. The systematics of this
lineage is investigated and, using an integrative taxo-
nomic approach based on molecular and morphological
evidence, a new systematic arrangement is proposed.
Under the new arrangement, the African family Biantidae
is sister to a well-supported monophyletic group of Neo-
tropical Samooidea comprised of five families: Samoidae
+ Hummelinckiolidae fam. nov. + Stygnommatidae +
Stenostygnidae new rank + Neoscotolemonidae fam. nov.
We present the first dated molecular phylogeny of the
Samooidea and discuss the ways in which the shifting
landscape of the Caribbean has shaped the opiliofauna of
the region for more than 50 million years–with dispersal
and vicariance both contributing to present day diversity
and distributions. Of particular interest is
Neoscotolemon
,
a genus that currently consists of only two described
species although we have discovered more than 20 addi-
tional species during our work. This clearly indicates that
the diversity of this genus is greatly underestimated–a
pattern that we have observed to be relatively common for
several genera of small litter dwelling harvestmen in the
Neotropics. The inferred evolutionary history of
Neosco-
tolemon
illustrates the dynamic two-way interchange
occurring between islands and nearby continents, in this
case via dispersal. This phenomenon has recently gained
the attention of many of those studying island biogeogra-
phy, and lends support to the idea that islands can serve as
both evolutionary museums and cradles of diversity.
Keywords: Opiliones, harvestmen, phylogenetics, system-
atics, Caribbean, biogeography, diversity
Oral presentation
Keystone individuals in spider societies:
some pros and cons
Jonathan N. Pruitt
1
, Carl N. Keiser
2
, Colin M. Wright
1
,
Alexander DeMarco
2
, Noa Pinter-Wollman
3
1
University of California-Santa Barbara, Santa
Barbara, CA 93160 USA;
2
University of Pittsburgh,
Pittsburgh, PA 51360 USA;
3
University of California-
Los Angeles, Los Angeles, CA 90095 USA
pruitt@lifesci.ucsb.eduMany animal societies rely on highly influential keystone
individuals for proper functioning. When information
quality is important for group success, such keystone indi-
viduals have the potential to diminish group performance if
they possess inaccurate information. Here, we test whether
information quality (accurate or inaccurate) influences
20
th
International Congress of Arachnology