GEOGRAPHIC VARIATION AND SPECIATION IN 
THE SOSIPPUS FLORIDANUS SPECIES GROUP 
(ARANEAE: LYCOSIDAE)* 
By Allen R. Brady 
Hope College 
Holland, Michigan 49423 
Introduction 
In March, 1959, while collecting in Goose Island State Park in 
Aransas County, Texas, I encountered the lycosid genus Sosippus 
for the first time. I collected four immature specimens that appeared 
to be an unfamiliar species of A gelenopsis, more darkly colored than 
most but with a similar color pattern and running upright over a 
sheet-web with a funnel-shaped retreat. Later when examining these 
specimens under a dissecting microscope, I was surprised to find a 
typical lycosid eye arrangement and other diagnostic features of the 
Lycosidae. My initial interest in Sosippus was in its web-building 
behavior and the possibility that this genus might be intermediate 
in position between the Agelenidae (whose habits it parallels) and 
the Lycosidae (whose structural features it exhibits). 
The Lycosidae, or wolf-spiders, are one of the most successful 
families of spiders. Most of them are ground dwelling forms that 
rarely use silk to capture their prey. Instead they rely upon their 
keen sense of touch, long, well-developed legs and powerful cheli- 
cerae to capture their prey. Many wolf spiders tend to wander in 
search of food, others hunt in the vicinity of their retreats which 
they only leave at night. 
The Lycosidae are adapted to a great variety of habitats and are 
represented by an abundance of individuals in these habitats. They 
are particularly interesting from the viewpoint of comparative sys- 
tematics since many species populations are found over a wide geo- 
graphic range including a diversity of habitats. For example, Lycosa 
carolinensis ranges from New England to southern Florida and 
westward to the Sonoran desert. This species changes little in such 
diagnostic features as the shape of the epigynum and the structure 
of the palpus, but does become lighter in color from north to south 
and east to west. As a general rule few taxonomic differences have 
been reported in widespread species populations of Lycosa. 
Geographic Variation and Speciation. In 1959 C. F. Roewer 
* Manuscript received by the editor April 3, 1972. 
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