1967] 
Reis kind and Levi — Theridiid Spider 
21 
There are four or five other known theridiid ant mimics: Cero- 
cida strigosa Simon, Helvibis brasiliana (Keyserling) and H. chilensis 
(Keyserling) , the male of Coleosoma floridanum Banks, and perhaps 
Hetschkia gracilis Keyserling. All except the Coleosoma create the 
impression of a petiole by a posterior elongation of the cephalothorax, 
most highly perfected in Cerocida where the “petiole” is rugose and 
sharply delimited from the rest of the carapace. Coleosoma floridanum 
has a highly constricted abdomen. But in Coleosoma only the males 
resemble ants, the females are characteristic sedentary theridiids 
hanging in a web. 
Anatea formicaria, unlike any other theridiid, produces its “petiole” 
by an elongation of the pedicel. In addition the dorsum of the 
“petiole” is rugose and has a distinct “node” as is typical in most 
ants. The abdomen is globose and highly shiny — very much like an 
ant’s gaster. 
Anatea formicaria is an accurate mimic of the small myrmicine 
ant Chelaner croceiventre (Emery), 2.6 mm long, which has been 
collected at the same locality as the spider. The color pattern (dark 
brown anterior and light, yellow-brown posterior) of both is quite 
rare in ants and is also found in specimens of Xiphomyrma tenuierius 
Emery, 2.9 mm long, and a species of Lordomyrma, 4.8 mm long, 
two myrmicine ants found in the same area of rain forest (E. O. 
Wilson, pers. comm.). Myrmicine ants have large and well-developed 
stings and are therefore quite objectionable to most potential preda- 
tors. Such a pattern may represent a mimetic complex with the ants 
being Mrillerian mimics and the spider a Batesian mimic of one or 
more ants. 
The genus Anatea will presumably key out to Euryopis in the key 
to theridiid genera (Levi and Levi 1962) but differs from Euryopis 
in having a simpler palpus (Figs. 3-6) and from all theridiid genera 
in the extraordinary development of the pedicel, and the strong first 
legs. Berland indicates that the female resembles the male. 
Anatea formicaria Berland 1927 
Figs. 1-6 
Description : Male. Carapace, sternum brown and sclerotized, 
legs lighter brown. Dorsum of abdomen light brown with four 
darker areas and a polished, shiny surface. Eyes subequal in size. 
Anterior median eyes about one-half diameter apart, a little more 
than one diameter from laterals. Posterior median eyes their radius 
apart, one and one-quarter diameters from laterals. The pedicel is 
unusually long with a joint at each end. The chelicerae are weak 
