M. R. Smith.
Two New North American Ants.
Psyche 41:211-213, 1934.

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Two New North American Ants
TWO NEW NORTH AMERICAN ANTS
BY M. R. SMITH
State College, Mississippi
Recently I received for identification from Illinois, two species of ants which I believe to be new to science. One
of these, a Leptothorax, was collected by Miss Mary Talbot at Plainsfield. To this species, which is characterized by its peculiar type of sculpturing, I have assigned the name foveata. The other new ant is a membser of the Lash Acan- thomyops group. Workers of this species were collected at Herrin, by Drs. T. H. Frison and H. H. Ross. Although this ant has many characters that will set it apart from its cogeners, I have chosen the name parvula for it because of its unusually small size.
Dr. W. M. Wheeler confirms my opinion that both of these species are new.
Leptothorax foveata sp. nov.
Worker :-Length 2.43 mm.
Head moderately large, excluding the mandibles, notice- ably longer than broad, with moderately convex sides, rounded posterior angles, and straight posterior border. Eyes large and prominent, oval, convex, placed near the middle of the sides of the head. Mandibles with 5 distinct teeth. Clypeus convex, with anterior border entire. An- tennse 11-segmented; scape lacking its greatest width or slightly more of attaining the posterior border of the head; first funicular segment longer than segments 1 and 2 taken together. Thorax short, robust, convex above ; viewed dor- sally the humeri are rounded, the pro-mesonotal suture very faintly visible, and the meso-epinotal suture only slightly more perceptible. Epinotal spines moderately long and robust, directed upward, outward and backward. Petiole viewed in lateral profile with feebly concave anterior sur-



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212 Psyche [December
face, faintly convex or flattened superior surface, which posteriorly rapidly descends toward the postpetiole. Post- petiole from above with convex node, which is very distinctly broader than long.
Head, thorax, petiole, and postpetiole, with foveate im- pressions, subopaque; those on the head much finer, espec- ially on the front and vertex where they are intermingled with very fine longitudinal rugulae; remainder of head, and dorsum of thorax, petiole, and postpetiole reticulate-foveate. Gaster glabrous, appendages very similar. Head, thorax, petiole, postpetiole, and gaster sparsely covered with short, erect, clavate hairs of a grayish or light yellowish color. Pubescence very fine and appressed, ex- tremely sparse, most easily discernible on appendages. Color deep reddish brown or ferruginous brown, with lighter appendages and gaster. Eyes and mandibular teeth black.
Described from a single worker, the type of which is in my collection.
The type worker, and an abnormal worker specimen were collected by Miss Mary Talbot in the nest of Aphssnogaster fulva subsp. aquia Buckley in a roadside ditch at Plainfield, Illinois on May 25, 1933.
This species is so different from all of the Leptothorax with which I am familiar that I am somewhat hesitant in trying to assign it to its proper taxonomical position. In Wheleler's key to the species of Leptothorax (Proc. Acad. Nat. Sci. Phila. p. 223, (1903) the specimen would appar- ently key down to the acervorum canadensis group. From canadensis the species can be distinguished by the following characters: (1) lack of a distinct longitudinal impression on the clypeus, (2) longer scape, (3) shorter thorax, (4) poorly developed pro-mesonotal and meso-epinotal sutures, and (5) differently shaped petiole and postpetiole. The most striking characteristics to me are the unusually prominent eyes of the worker, as well as the peculiar type of sculpturing; the species has, therefore, been very aptly named f oveata.




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19341
Two New North American Ants
Lasius (Acanthomyops) parvula sp. nov.
Worker :-Length 3.0 mm.
Head, excluding the mandibles, only very slightly longer than broad, narrower in front than behind, and with straight or very feebly excavated posterior border and reg- ularly convex sides. Mandibles, each with 6 to 7 very dis- tinct teeth and some smaller, less defined denticulse; the superior surface without teeth as with L. interjectus. Eyes extremely small, resembling somewhat those of L. flavus subsp. nearcticus, apparently with not more than 6 omma- tidia in their greatest diameter. Antenna1 scapes short, scarcely if at all, exceeding the posterior border of the head. Petiole apparently lower and thicker than with L. interjec- tus; anterior surface convex, posterior surface flattened, and superior surface transverse, entire.
Body, and cox= and femora of legs covered with rather abundant, moderately long, erect, pale yellowish hairs. Pube- scence fine and appressed, sparsely covering all parts of body except the appendages.
Pale yellowish, especially the gaster, which is lighter than the other parts of the body.
Described from 4 workers, the cotypes of which are in my collection.
These ants were collected by Drs. T. H. Prison and H. H. Ross of the Illinois State Natural History Survey at Herrin, Illinois, on October 12, 1933. According to these gentlemen the ants were collected in the soil beneath a rotten log in an open wood lot. They were associated with Lasius niger var. That this species belongs to the subgenus Acanthomyops is clearly indicated by the 3-segmlented maxillary palpi of the workers. At a glance one would assign the species to L. flavus nearcticus because of the pale color, small eyes and general size of the workers. I believe this to be a perfectly valid species as evidenced by the following characters : (1) the extremely small size of the worker, (2) unusually small eyes,
(3) very short antenna1 scapes, (4) lack of teeth on the superior surface of the mandibles, and (5) pale yellow color. This is apparently the smallest North American Acanthomyops that has yet been described.



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