20th International Congress of Arachnology

169

DENVER MUSEUM OF NATURE & SCIENCE

REPORTS

No. 3, July 2, 2016

CO1 and combined trees. Cluster analysis on the intensity

of 1D electrophoresis gel spots using Bray-Curtis similar-

ity is possible to define 4 clusters that correspond with

geographical distribution of the specimens, except one

specimen from near Cooktown (Kings Plains) cluster with

southern specimens. Similarity and permutation analysis

of LC/MS-MS results indicate that some northern speci-

mens have more similar venom to southern specimens

than to other northern individuals. However, populations

from an island in the middle of the range differ largely

from northern and southern specimens. Combining the

analyses, it is just possible to assume that a population of

S. crassipes

located along the Jardine River (northern Cape

York) is different from all other

S. crassipes

, but the south-

ern individuals are also different from specimens from the

northern and middle part of the distribution range.

Keywords: CO1, 16S, venom proteomics, systematic,

Australian tarantula

Oral presentation

Filling pieces in the scorpion venom puzzle

Carlos E. Santibáñez-López

Departamento de Medicina Molecular y Bioprocesos.

Instituto de Biotecnología, Universidad Nacional

Autónoma de México. 2001 Av. Universidad, Cuer-

navaca, Morelos 62210, México.

caecentrus@gmail.com

Scorpion venom is a library of several compounds, tradi-

tionally divided into two fractions: toxic and non-toxic.

Whereas the non-toxic fraction includes mixtures of

mucopolysaccharides, lipids, free amino acids, enzymes,

protease inhibitors and biogenic amines. The toxic fraction

basically consists of peptides that are highly specific to ion

channels of excitable cells. Over more than 400 million

years, the venom arsenal has assembled into an effective

weapon that works for defense and offense. Traditionally,

venomic studies consist of the isolation and biochemical

characterization of specific peptides (e.g., toxins) from

the venom mostly from buthid species. With the advent

of the next generation sequencing, scorpion venom gland

transcriptomes have improved our knowledge on target

genes (e.g., those coding for toxins), and revealed different

components with no resemblance to known toxin types.

It also showed us the presence of different genes coding

for toxins or other venom components which may not be

expressed in the venom or suffer from post-translational

modifications. However, these transcriptome studies cover

a narrow taxonomic sampling including several buthid

species, plus fewer species from seven non buthid families.

Here, firstly the status quo of venom biodiversity is summa-

rized. Then, unpublished preliminary data of four venom

gland transcriptomes of four non buthid scorpion families

(two of them unexplored before) are presented. Finally, the

phylogenetic affinities of some poorly known components,

including scorpion calcines and La1-like peptides, reveal

partially concordance with scorpion phylogenetics, sug-

gesting the utility of these toxins and venom components

as molecular markers in phylogenetic studies.

Keywords: venom, toxins, calcines, scorpions, La1-like

peptides

Oral presentation

Influence of the biogeospatial environment

on the distribution of spider communities

Jason Schmidt

, Katherine Russell

, Dawn Olson

, Alisa

Coffin

Department of Entomology, University of Georgia,

Tifton, GA, USA;

Odum School of Ecology, University

of Georgia, Athens, GA;

Crop Protection, USDA, Tifton,

GA, USA;

Southeast Watershed, USDA, Tifton, GA, USA

jschmid2@uga.edu

The maintenance of local biodiversity is an important

aspect of the long-term sustainability of agricultural

production. Maintaining biodiversity, especially in regards

to predator species, promotes natural pest control and

many other ecosystem services. Spiders (Araneae) often

prey upon common pest species, making them a beneficial

component of agroecosystems. Spider species richness and

diversity varies across landscapes and is often correlated

with certain abiotic factors. This project investigates how

four geospatial attributes—elevation, soil moisture, NDVI,

and distance to edge habitat—influence spider species

distributions across a farm-scape in South Georgia.

Samples for the project were obtained from pitfall traps

International Congress of Arachnology