20th International Congress of Arachnology

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wolf spiders originally described in the genus Lycosa will
be presented. In this summary the morphological charac-
teristics that were used to establish the genera Gladicosa,
Rabidosa and Tigrosa will be illustrated. The same char-
acteristics are being utilized to establish the new genus
Lentacosa, composed largely of North American species
originally placed in the genera Lycosa and Hogna. The
genera Gladicosa Brady, 1980, Rabidosa Roewer, 1954 and
Tigrosa Brady, 2012 have been shown to be distinct from
the largely Mediterranean distributed Lycosa , exemplified
by Lycosa tarantula (Simon) and Hogna, exemplified
by Hogna radiata (Latreille). Eleven species are repre-
sentatives of the new genus Lentacosa which is primarily
concentrated in the southeastern United States. Members
of this genus can be distinguished by a combination of
characters including the color pattern on the dorsum of
the cephalothorax, a solid black venter on the abdomen,
and the structure of the male and female genitalia, distin-
guishing them from Lycosa and Hogna. Illustrations will
be utilized to demonstrate these defining characters.
Keywords: systematics, Lycosidae, Lycosa, Hogna , North
America, Herb Levi symposium
Student - oral presentation
Targeting or escape: differences between
jump types in a jumping spider
*Erin E. Brandt, Neil Chan, Damian O. Elias
University of California, Berkeley Department of
ESPM 130 Mulford Hall Berkeley, CA 94720, USA
Jumping is a mode of locomotion convergently evolved
in many arthropod taxa. Although well-studied in insects
such as grasshoppers, less study has been conducted in
spider jumping. In particular, jumping spiders (Araneae:
Salticidae) use jumping as a primary means of locomo-
tion and utilize a very different jumping mechanism from
other animals. In this experiment, we used Habronattus
conjunctus, a desert-dwelling jumping spider, to investi-
gate how jumping differed between escaping from danger
and attempting to reach a specific endpoint. We found that
spiders spend more time preparing for targeted jumps and
attain relatively lower velocities. We also noted imprecise,
often unpredictable aerial paths, and clumsy landings
in escape jumps. We suspect that the gains in speed and
unpredictability are so important to predator evasion
that a high degree of physical robustness has evolved
in these spiders to allow them to withstand unwieldy
landings. Finally, although we carefully calibrated the
targeted jump setup to mimic distances that spiders would
naturally jump, we found that spiders were unable to
attain a distance that they could otherwise easily attain
in an untargeted jump. We explore accuracy at different
distances and speculate as to why distances on targeted
jumps are so much shorter.
Keywords: jump, salticid, locomotion, jumping spider
Poster presentation
Signal in the noise: use of long-term
spider data
Sandra Brantley
Museum of Southwestern Biology, University of New
Mexico, Albuquerque, NM, 87131-0001, USA
As is true for most predators, spiders tend to be rare at
the species level, making ecological analyses difficult.
However, even with low numbers, long-term data can
increase our ability to see patterns associated with abiotic
and biotic factors. At Bandelier National Monument in
the Jemez Mountains of northern New Mexico, I have
been working with ground-dwelling spiders since 1997,
documenting habitat affinities and species composition
changes over time. Because the southwestern US is pre-
dicted to become warmer and drier with climate change,
forested areas are expected to decline while areas domi-
nated by shrubs and small trees are expected to increase.
Here I compared lycosid spiders between a ponderosa
pine (PP) forest and more open pinyon-juniper (PJ)
woodland, asking if the spiders are specific to a given
habitat or season and what that may mean for future
climate-related changes. Spiders were collected in pitfall
traps 4 times/year, providing both seasonal and annual
relative abundance data. Lycosid taxa included Alopecosa
kochi, 6 Pardosa spp., Schizocosa mccooki, and Varacosa
gosiuta. Periods of high abundance varied with taxon:
54 DENVER MUSEUM OF NATURE & SCIENCE REPORTS | No. 3, July 2, 2016
Cushing