R. E. Gregg.
Taxonomic Notes on the Ant, Componotus cooperi Gregg.
Psyche 60:102-104, 1953.

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TAXONOMIC NOTES ON THE ANT,
CAMPONOTUS COOPERI GREGG
Department of Biology, University of Colorado Several years ago I described an unusual Central Ameri- can ant, naming it cooperi and placing it in the genus Camp- onotus (Gregg, 1951). The specimen, a single alate female, was sent to me by Dr. W. L. Brown, for description and illustration, together with some comments on its affinities. Since the fades of the ant is astonishingly like those of Camponotvs, and particularly because of its close similarity to members of the subgenus Myrmostenus, both of us con- cluded it belonged to these groups. It was accordingly placed in the genus Cunzponotus and as a new species in the above subgenus which Emery had erected in 1920 to contain several South American species previously de- scribed by him. Unfortunately, all of these ants are known only from the female caste, no workers having as yet been found (Emery, 1925).
Recently, Dr. Brown checked the type of cooperi, and it now develops that the ant cannot possibly be considered a form of Cumponotzis owing to the fact that the antennae are 10-segmented instead of having 12 articles character- istic of the above named genus. The description and figure also give 10 as the antenna1 joint number, so the mistake obviously lies in our interpretation of the relationships of cooperi. The slip is attributable to the amazing similarities in habitus (except smaller size) between the new ant and those in the subgenus Myrmostenus, which resemblances are probably to be regarded as the products of convergent evolution.
Dr. Brown has offered the following statement (in litt.) with respect to his current view on the matter. "Although the proventriculus has not been dissected out for examina- tion, it appears very probable that this species [cooperi]



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1953 j Gregg - Camponotus cooperi 103
really belongs in the vicinity of Myrmelachista, particularly of the subgenus Decamera Roger. The species described by Menozzi (1935) as Aphomomyrmex (Neaphomus) goetschi from Chile also falls close into this group, according to his characterization and Wheeler's key of 1922. The genera of the tribe Myrmelachistini appear to be in confusion, partly due to the unsatisfactory nature of the antennal club as a stable group character. A female of Myrmelachista (Dec- ame?x) paderezvskii Forel in the Museum of Comparative Zoology is almost as large as the cooperi female, but is much less aberrant in many ways. At present it appears best to consider Menozzi's goetschi, wiith cooperi, as mem- bers of an independent genus bearing the name Neaphomus enozzi."
There is no doubt that cooperi must be removed from Cum-ponotus and placed in another, and more appropriate, genus, and it seems advisable to do so without involving any new generic names at 'this time, even though the group chosen may be shown subsequently to be an artificial as- semblage. However, I do not concur with Dr. Brown's treatment quoted above, which would produce certain no- menclatural changes, but feel thak in view of the unsatis- factory nature of the classification of the various species concerned, it is much safer to make as few shifts as pos- sible, and to place the ant in question in the genus Apho- momyrmex into which group it falls with no difficulty ac- cording to Wheeler's key to the genera written in 1922. Wheeler expressly states that the females of this genus have 10-segmented antennae, and since no workers ac- companied the specimen of cooperi, it is impossible to state what their antennal condition may be and we are forced to rely entirely upon the segment- number of the female. Furthermore, while the genus Myrmelachista (subgenus Decainera) possesses 10-jointed antennae, the genus as a whole has a differentiated club, which is absent from the coo-peri female, the joints of same showing a gradual in- crease in thickness toward the tips of the antennae. And finally, 1 am informed by Dr. Creighton that females of the genus Myrmelachista he has seen look much like those of Iridomyrmex in general appearance (despite the difference in subfamily allocation), which would make those species



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decidedly unlike the cooperi fema1e.l
Wheeler gives the distribution of Aphomomyrmex as Ethiopian and Myrmelachista as Neotropical, but this is no proof the former could not occur in the New World trop- ics, especially as the fauna of that region is far from ex- haus1tively studied. Moreover, Menozzi (1935) described a Neotropical Aphomomyrmex nearly twenty years ago, so it is not unknown from this side of the Atlantic. And the genus which Dr. Brown proposes, Neaphomus, has been regarded as a subgenus of Aphomomyrmex.
In view of the above discussion, thereflore, and particular- ly since we are as yet unable to associate the worker caste with the female of the species concerned, I submit the following correction, and the synonymy then should read : Aphomomyrmex (Neaphomus) cooperi ( Gregg) , new combhati,on for Camponotus (Myrmostenus) cooperi Gregg, 1951, loc. cit.
EMERY, C.
1925. Subfam. Formicinac. Genera Insectoruin. Fsiric. 183. GREGG, R. E.
1951. Two new species of exotic ants. Psyche. 58:77-84. MEXOZZI, C.
1935. Le Formic-he del Cile. 2001. Jahrb. Syst., 67:319-336. WHEELER, K. M.
1922. KP~S lo the genera and subgenera of ants. Bull. Aini I . MIIG. Xat. Hist., 45 :631-710.
In contrast. Dr. Brown believes, "there is no e-sentisit diit't mmt 111 the clavation of the antennae between cooperi and pertain 1)t cam 7.n species. In fact. cooperi may be said to have stronger and 111orr definite vlavation of the funiculi than does 31. (D.) pridereu'skii female. Furtb~r- more, certain species of Jlyrmelcichinta (eg. 31. .&warme) an- ~inallt~i replicas of S. goetschi in all essential habitus characters, inchidir~gII~e lengthened head.
Thus, while to Creighton sonic Xy~nzekichisi~r females inav look like Iridomyrmex of the same paste . . ., at least soinp h;i\ c a11 appeiirance very much different from that of Iridomyrmcx."



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