A NEW SPECIES OF MEGALOMYRMEX 
FROM THE CHILEAN ANDES 
(FORMICIDAE, HYMENOPTERA) 
By George Ettershank* 
Department of Entomology, Cornell University 
The genus Megalomyrmex has generally been thought of as 
associated with the wet tropical rain-forests of the New World. 
Members of the goeldii species-group in particular forage openly on 
the rain-forest floor and tend Homoptera on low bushes. It was thus 
a considerable surprise to receive a few specimens of a goeldii group 
species collected only 25 miles from the crest of the Andes in Chile. 
This is a new species, and its discovery extends the genus into a new 
habitat. 
The specimens under study were found by Mr. E. Ackerman at 
Pachon Peak (Cerro Pachon), near La Serena, Coquimbo Province, 
Chile, at an altitude of 8500 dz 100 feet. The collection site is a 
rather flat hill crest with sparse low shrub cover; the substrate is 
andesite boulders resting on andesite rubble and soil. The colonies, 
Mr. Ackerman notes, were populous and by no means rare. A few 
live workers were sent to Dr. Caryl P. Haskins of the Carnegie 
Institution of Washington, who placed the workers in a laboratory 
nest; a few eggs were laid, from which three larvae were reared. All 
the material was later sent to me; this consisted of four live workers 
and three preserved larvae. My thanks are offered to Dr. Haskins 
for allowing me to study this interesting species. 
Measuring techniques and abbreviations quoted below follow the 
system of Brown ( 1 ) while certain other terminology follows Etter- 
shank (2). 
Megalomyrmex bicolor n. sp. 
Holotype worker (measurements in millimeters; those for two 
parat}q>e workers are enclosed in parentheses) : total length, TL 4.8 
(4.6, 4.4), head length, HL 1.04 (0.98, 0.94), length closed man- 
dibles, ML 0.24 (0.22, 0.20), alitrunk length, WL 1.34 (1.32, 
1.26), head width, HW 1.00 (0.92, 0.88). Cephalic index, Cl = 
100 HW/HL = 96 (94, 94), mandibular index = 100 ML/HL 
^Present address: Department of Zoology and Comparative Physiology, 
Monash University, Clayton, Victoria, Australia. This article is a partial 
result of work done under U. S. National Science Foundation Grant GB-2175, 
principal investigator, W. L. Brown, Jr. 
Manuscript received by the editor January 4-, 1964 
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