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Carajas paraua
sp. n. from State of Pará, both are Brazil-
ian species found only in caves, and lack eyes completely.
Another amazing finding, are the new species of
Nasuto-
nops
gen. n. which are characterized by the presence of a
projected clypeal horn, unique among caponiids.
Keywords: Taxonomy, new species, haplogynae, new
genus, Neotropical region
Oral presentation
Venom evolution in the genus
Tetragnatha
facilitates adaptive radiation and mate
recognition
Michael S. Brewer
1
, Emily Bulger
2
, Pamala Zobel-
Thropp
3
, Greta Binford
3
, Rosemary G. Gillespie
2
1
Department of Biology, East Carolina University,
Greenville, North Carolina, USA;
2
Department of Envi-
ronmental Science, Policy, and Management, University
of California, Berkeley, California, USA;
3
Department of
Biology, Lewis & Clark College, Portland, OR, USA
brewermi14@ecu.eduVenoms are considered a key innovation that allowed
ecological diversification in a number of lineages includ-
ing snakes, anguimorph and iguanian lizards, and cone
snails. Venoms are complex cocktails of bioactive com-
pounds with high target specificity and serve multiple
functions. Commonly, venom serves a role in predation
and defense but can be involved in intraspecific conflict
and mate recognition. Sexual dimorphisms have been
observed in the venoms of several taxa, indicating a
potential role in mate recognition. This sets up a possible
dual role of venoms in both ecological divergence and
mate choice that could influence reproductive isolation of
populations through local adaptation. Though disparities
in venoms between sexes can sometimes be explained by
differences in feeding behavior, evidence also suggests that
venom can play a role in intraspecific communication.
Our work on
Tetragnatha
venoms, namely transcrip-
tomics and proteomics, shows most species display sexual
dimorphisms; males express high molecular mass venom
components that are present at much lower levels or
absent in females. Additionally, a Hawaiian clade has
undergone an adaptive radiation with concomitant
evolution of venom peptides, including the derivation of
novel venom gene families. Given the unusual mating
behavior (cheliceral locking) in many tetragnathids,
these dimorphic venom components may play a role in
mate recognition while other components have evolved in
response to dietary niche partitioning. Here we present the
current state of our ongoing tetragnathid venom research.
Keywords: venom, sexual selection, mate recognition, adap-
tive radiation, transcriptome, proteomics, gene expression
Oral presentation
Retreat site selection in two species of Sky
Island scorpions from Arizona
Christopher A. Brown
1
, Jamie E. Becker
2
1
Department of Biology, Box 5063, Tennessee Tech
University, Cookeville, TN 38501 USA;
2
Department of
Biological Sciences, 217 Life Sciences Bldg., Bowling
Green State University, Bowling Green, OH 43403, USA
cabrown@tntech.eduThe Sky Island Mountains of Arizona and New Mexico
harbor a number of species of small scorpions in the
genus
Vaejovis
. As is the case for many scorpions, little is
known about the ecology or behavior of these species. In
the present study, we examined size and thermal charac-
teristics of retreats (rocks) for two Sky Island Vaejovis
scorpions:
V. electrum
from the Pinaleno Mountains and
V. cashi
from the Chiricahua Mountains. For both species,
we measured the size of rocks selected as retreat sites as well
as the size range of representative rocks in the habitat. We
also recorded thermal profiles under rocks that were used by
scorpions and those that were not used. In the laboratory,
we examined thermal preferences of gravid and non-gravid
females from each species, using a thermal gradient. Both
V.
electrum
and
V. cashi
were found under rocks that were sig-
nificantly larger and thicker than the average rock size for
that habitat. Although the mean temperature under these
selected rocks did not differ from the mean temperature
found under rocks unoccupied by scorpions, both the range
and the variance in temperature were lower under rocks
occupied by scorpions.
Vaejovis electrum
selected larger
rocks than did
V. cashi
, although this may be due to the fact
that the Pinaleno site had rocks of a larger mean size from
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DENVER MUSEUM OF NATURE & SCIENCE
REPORTS
|
No. 3, July 2, 2016
Cushing