THE SPIDER GENUS TINUS (PISAURIDAE)* 
By James E. Carico 
Department of Biology, Lynchburg College 
Lynchburg, Virginia 24501 
This paper is the third in a series of generic revisions of the pisau- 
rids of the western hemisphere. It represents the first attempt to 
bring together all published information with the results of an ex- 
tensive examination of all available collections of the genus. For 
those workers who are particularly interested in the fauna of the 
continental United States, Tinus is one of four pisaurid genera found 
in the area. Dolomedes and Pisaurina were revised earlier (1973 & 
1972 resp.) and Trechalea is in progress. 
Unfortunately there are no published accounts of the natural 
history of any Tinus species. Based on a few labels with T. nigrinus 
specimens and the author’s sketchy observations, it seems that the 
habitat is quite similar to Dolomedes , i.e. on the faces of rocks and 
tree trunks, and in trash or vegetation near the margins of bodies of 
fresh water. The female carries the spherical egg sac in a typical 
pisaurid manner by holding it with the chelicerae and a thread from 
the spinnerets. The egg sac is white, opaque or translucent when 
new, and usually darkens to a brownish color with age. Only nur- 
sery webs for T. nigrinus and T. ursus are known, and their descrip- 
tions are given in the Natural History sections of each species. 
The superficial body shape, eye patterns, and biology of Tinus 
suggest an affinity with Dolomedes. There is also a superficial re- 
semblence to Thaumasia; but whether Tinus might be a subgenus 
of the latter as Gertsch suggests (1940) is a matter that must await 
a revision of that genus. In any case, Tinus is clearly a group distinct 
from all other pisaurids studied and is strictly limited in its distribu- 
tion to southern North America, from the southwestern United 
States southward to Costa Rica in Central America. 
Too little is known about the genus to confidently trace its phylog- 
eny, but the apparently restricted distributions of four of the seven 
species suggests the kind of stream isolation situation described 
earlier for Dolomedes (Carico, 1973). 
* Manuscript received by the editor April 15, 1976. 
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