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Psyche 
[Vol. 94 
the Museum fur Naturkunde, Stuttgart, with the reference number 
Do-493 1-M. He has also provided us with four more workers, in a 
piece labeled Do-4484-M. 
Baroni Urbani was right. The additional, better preserved 
workers are identical or close to L. neotropicus, and prove to belong 
to the Leptomyrmecini beyond any reasonable doubt. In addition to 
being so close in overall habitus to the living species of Leptomyr- 
mex as to fall easily within the limits of this genus, the material 
shows the following distinctive traits in common with that Old 
World genus: 
(1) Slit-shaped anal orifice. 
(2) Masticatory border of mandibles smoothly rounded at the 
basal angle and lined with more than 15 denticles of uniform size, as 
opposed to fewer than 10 teeth, usually 5-6, decreasing in size from 
apex to base in species of Camponotus. 
(3) Anteriormost point of antennal socket very close to the poste- 
rior clypeal border (in Camponotus the two are widely separated). 
(4) Large metapleural gland orifice and prominent bulla (in 
Camponotus bulla small and orifice absent). 
(5) Metathoracic spiracles on dorsum of alitrunk (usually lateral 
in Camponotus). 
In addition, Wilson has acquired a male that appears to be a 
leptomyrmecine, although it possesses at least one trait (absence of 
the radial cell) that might eventually justify separating it at the 
generic level from both Leptomyrmex and Leptomyrmula. 
Status of Leptomyrmex neotropicus Reexamined 
The main features of a well-preserved Leptomyrmex are depicted 
in Figure 1. As noted by Baroni Urbani (1980) for the L. neotropi- 
cus types and confirmed with the new worker specimens, the habitus 
of the fossil species is closest to L.fragilis (= L. gracillimus) of New 
Guinea, Ceram, and Aru among the living species. This assessment 
is based on the revision of Leptomyrmex by Wheeler (1934) and the 
examination of large new collections of that genus placed in the 
Museum of Comparative Zoology during the ensuing fifty years. L. 
neotropicus differs from fragilis in its smaller size, even narrower 
head, projection of the compound eyes beyond the lateral borders of 
the head, and more concave masticatory borders. In a genus with a 
relative scarcity of worker characters, the small size is especially 
notable. The specimen shown in Figure 1 possesses the following 
