20th International Congress of Arachnology

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68 DENVER MUSEUM OF NATURE & SCIENCE REPORTS | No. 3, July 2, 2016
Cushing
Oral presentation
DNA barcode data accurately identify
higher spider taxa
Jonathan A. Coddington1, Ingi Agnarsson1,5, Ren-Chung
Cheng2, Klemen Čandek 2, Amy Driskell1, Holger Frick3 ,
Matjaž Gregori č 2 , Rok Kostanjšek4 , Christian Kropf 3 ,
Matthew Kweskin 1, Tjaša Lokovšek2 , Miha Pipan2,6, Nina
Vidergar2, Matjaž Kuntner1,2
1National Museum of Natural History, Smithsonian
Institution, Washington, DC, USA; 2EZ Lab, Institute
of Biology at Research Centre of the Slovenian
Academy of Sciences and Arts, Ljubljana, Slovenia;
3Department of Invertebrates, Natural History
Museum Bern, Switzerland; 4Department of Biology,
University of Ljubljana, Slovenia; 5Department of
Biology, University of Vermont, Burlington, VT, USA;
6Currently at: Department of Biochemistry, University
of Cambridge, Cambridge, CB2 1GA, United Kingdom
Most spider species are undescribed. Can DNA barcodes
accurately assign an unidentified species to genus or
family? We built a carefully chosen test library of CO1
sequences from 49 families, 313 genera, and 816 species
of spiders to assess the accuracy of genus and family-
level assignment. We BLASTed each sequence against
the entire library and retained the top ten hits (PIdent,
range 75-100%). Generic identifications were accurate
(less than 5% errors) at PIdent > 95 and families at
PIdent ≥ 91. More species/genus and genera/family in
the library increases accuracy: above five genera per
family and fifteen species per genus all higher taxon
identifications were correct. The quality of the underly-
ing database is important; many outliers in our dataset
could be attributed to taxonomic and/or sequencing
errors in BOLD and GenBank.
Student - oral presentation
Scorpion tail strikes: a trajectory shape
analysis
*Pedro Coelho, Antigoni Kaliontzopoulou, Mykola
Rasko, Arie van der Meijden
CIBIO-InBIO (Research Centre in Biodiversity and
Genetic Resources), Vila do Conde, Portugal
Whole-organism movement provides insights into how
animals perform ecologically vital tasks. In scorpions
there is a unique biomechanical challenge: the meta-
soma (the “tail”, a continuation of the body rather than
a true tail) when used defensively, is capable of reaching
speeds up to 2 m/s, shifting the center of mass position
abruptly and requiring large reaction forces; it can also
represent 25% of the total body weight. In this work, we
quantified performance differences from 179 defensive
strikes produced by 23 individuals. Using high-speed
videography, we calculated anatomical and kinematic
variables as well as the 3D shapes from the stinging tra-
jectories. Scorpion morphology and kinematic variables
exhibited a significant association across species after
taking phylogeny into account. Moreover, the multivari-
ate association between traits indicate that not only shape
and kinematic variables are correlated but also that open
(unfolded) trajectories present higher velocities. In other
words, this indicates that certain strike trajectory shapes
allow for faster strikes than others. Understanding how
the scorpion defensive system operates can provide new
additions to stability under perturbation models.
Keywords: scorpions, trajectory shape, defensive strike,
comparative kinematics, functional morphology
Student - poster presentation
Characterization of the Venom Proteome
for the Wandering Spider, Ctenus hibernalis
(Aranea, Ctenidae)
*T. Jeffrey Cole1, Patrick A. Buszka1, Ronald N. Hunsinger1,
James A. Mobley2, Robert A. Hataway1
1Department of Biological and Environmental
Science, Samford University, Birmingham, AL
35229-2234; 2Department of Surgery, University of
Alabama-Birmingham, Birmingham, AL, 35294-0113
Spider venom is a rich multicomponent mixture of neu-
rotoxic polypeptides. The venom of a small percentage
of the currently classified spiders has been categorized.