G. C. Wheeler and E. W. Wheeler.
New Forms of Aphœnogaster treatœ Forel from the Southern United States (Hym.: Formicidæ).
Psyche 41:6-12, 1934.

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Psyche
[March
NEW FORMS OF APHBNOGASTER TREATS FOREL
FROM THE SOUTHERN UNITED STATES
(HYM. : FORMICID#)
BY GEORGE C. AND ESTHER W. WHEELER
University of North Dakota
In describing new forms of Aphsnogaster treatse Forel, we have found the original specific description (1886) too brief. It seems desirable, therefore, to give here a few additional characteristics which we have found useful in comparisons.
WORKER. Length of head exclusive of mandibles 1v2 times its greatest width. Scape 1Ya times the length of the head; lobe % to
the length of the scape. The long
flange bordering the lobe posteriorly1 is low and the anterior surface of the lobe is convex except that the distal portion has a small concavity between the posterior and anterior flanges. The short anterior flange arising at an acute angle from the posterior one disappears into the anterior convexity.
(See Fig. la and b.) The base of the
epinotum is twice the declivity.
Head coarsely and longitudinally rugoso-reticulate with surface between the reticulations finely punctate. Frontal
area with a median longitudinal ridge. Transverse stria- tions on the dorsal surface of the epinotum commence at the base and merge into reticulations or indistinct stria- tions in the region between the spines. Posterior surfaces of nodes densely and irregularly punctate. Mandibles hairy. Thorax dark ferrugineous; head and abdomen above f usco-ferrugineous.
We have been unable to procure a female of A. treats. 'In this paper the anterior part of the lobe is that surface which faces forward when the scape is appressed to its groove in the head; the posterior, the area concealed thus.
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19341 New Forms of Aphsenogaster treat8 7 MALE.
Epinotum % the entire thorax, slightly longer than mesonotum. Spines usually reduced to blunt protub- erance~.~ Base 3 times the declivity.
Head densely punctate. Mesoscutum smooth and irregu- larly pitted laterally, finely punctate above, coarser behind ; scutellum punctate, mesopleurse smooth, striated near an- terior border. Anterior half of base of epinotum smooth, posterior half of its base punctate ; its declivity irregularly cross-striated. Nodes faintly punctate, postpetiole with a narrow band of lateral longitudinal striations. Abdomen shining and smooth except the posterior halves of petiole and postpetiole, which are rugosely and finely reticulate.
A few hairs on the head, almost none on the thorax; scattered longer hairs on the abdomen. Dark fuscous; legs and tip of abdomen, fusco-testaceous. Mandibles, anterior edge of pronotum, tarsi, and genitalia, testaceous.
This supplementary description of the male is taken from a specimen sent us by Dr. W. S. Creighton, collected at Lookout Mt., Fort Payne, Ala., and considered by him to be typical.
Aphaenogaster treatae subsp. pluteicornis, new subspecies WORKER. Length 6 mm.
Differs from the typical treatse in the following details: Scape usually IVg the length of the head exclusive of the mandibles. Antenna1 lobe is about VA, the length of The epinotal spines of the males of A. treatas are probably variable likewise, although Fore1 (1886) says ''arm6 de deux 6pines." In the type nest of A. phiteicornis the spines are vestigial, being represented by low rounded protuberances. Sometimes these resemble spines broken off near the base. However, small hairs have been found on the apparently broken end, and also, an adult male was discovered still inside the untorn pupal exuvium with this same rounded projec- tion. These facts nullify the possibility of the stumps being broken spines.
Another nest of this same subspecies, collected at Ivanhoe, Texas, has long slender spines on all males. Emery (1895) in speaking of A. treatse males reports: "Unter den mir vorliegenden 3 8 aus D. Columbia finde ich nur eins mit langen und an der Spitze stumpfen Dornen; bei alien andern, darunter 2 aus demselben Flaschen wie das bedornte Exemplar sind mir stumpfe Beulen zu sehen. Ein leider sehr beschadigtes Originalexemplar des 8 aus N. Jersey hat kurze, stumpf e Dornchen."




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8 Psyche [March
the scape.
The flange bordering it posteriorly is higher and the anterior surface of the lobe next to this flange is very concave. {See Fig. 1c & Id.)
Spines on the epinotum
a little longer, varying from $$ to $ the base. Hairs even more sparse ; short and coarse on head, pros- ternurn, doma of thorax and petiole; finer on abdomen. A few scattered, very small hairs, suggestive of rudimen- tary pubescence, on the gastric dorsum in addition to the usual longer hairs.
FIG. 1. a, left antenna1 lobe of Aphefiogaster treats, anterior view; b, lateral view of same; c, left antenna1 lobe of Aphawogaster pluteicomis, var. pkJahomem&, anterior view; d, lateral view of same.
Head not so coarsely rugoso-reticulate. The feeble trans- verse striations on the dorsum of the epinotum are almost immediately indistinguishable from reticulations. Petiole and postpetiole more faintly punctate laterally and less rugose above. Very fine reticulations of the first gastric segment extend indistinctly to the posterior edge. Ferrugineous throughout except the abdomen which varies from ferrugino-fuscous to ferrugino-testaceous with a tendency to be lighter at the apex.
FEMALE. Length 8 mm.
Differs from the worker in having the lobe a trifle longer in proportion to the scape.
Length of head exclusive of




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19341 New Forms of Aphsenogaster treatse 9 mandibles Iys times the width. Scape shorter, 1 1-15 times the length of the head.
Sculpture coarser, gaster duller. Mesoscutum striated above longitudinally ; on the mesoscutellum these ridges curve into cross striations posteriorly. Transverse striations of epinotum regular, not I-eticulate. Petiole rugose, reticu- lations becoming somewhat diagonally striated behind. Area between the reticulations punctate. Keel on the ven- tral surface sharp. Anterior dorsum of postpetiole reticu- late, somewhat coarser and transversely striated behind. First gastric segment finely striated longitudinally at the base, merging into fine reticulations and fading out pos- teriorly.
Hairs relatively shorter and more abundant. Color ferrugineous to fusco-ferrpgineous, lighter speci- mens with darker parapsidal furrows.
Metanotum, teeth
of mandibles, area between ocelli, margins of thoracic sclerites, bands on the apices of gastric segments, fusco- ferrugineous ; when completely retracted the lighter bands are concealed.
MALE. Length 5 mm.
Differs from the male of A. treat2 as follows : Irregularly transverse ridges of the epinotal declivity fewer. Epinotal spines ~ariable,~ sometimes reduced to low rounded protuberances. Thorax piceous, femora and tibiae darker also.
These ants were collected by the authors in open woods (mostly Quercus maritandim Muench.) , where the soil was a sandy loam.
Oklahoma: Poteau. VI-17-'29. Numerous workers, 1 dealated female, 3 winged females, 4 males, and a few larvae and pupae. On a steep slope in the soil and under dead leaves beside a stone. (Type nest.) Oklahoma : Poteau. VII-16-'22. Small colony under a stone on a steep hillside.
Texas : Ivanhoe (Fannin County). VI-27-'29. Numerous workers, 8 dealated females; 7 winged females, 3 males, a few larvae and pupae. In the buried end of a small decayed branch.




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10 Psyche [March
Aphaenogaster treatae pluteicornis var. oklahomensis, new variety
WORKER. Length 5%-6 mm.
Differs from A. treat8 pluteicornis in the following re- spects : Scape 1% to 1% the length of the head exclusive of the mandibles. Lobe Vå the length of the antennae and more concave next to the posterior flange, which is higher. (See Fig. 1c & Id.) Epinotal spines about % the base, but variable. Epinotum more definitely striated. The first dorsal segment of the gaster more faintly reticulate. Pos- terior surface of the node of the postpetiole less densely punctate above. Fulvous, with head more ferrugineous, teeth of mandibles fuscous, and gaster light f ulvo-f uscous. FEMALE. Length 8 mm.
Differs from the female of A. pluteicornis in these char- acteristics: Antennse shorter, scape 1 1/11 times the length of the head.
Lobe y3 the scape. Posterior dorsum of the petiole more roughly reticulate, forming indefinite cross- striations. Postpetiole more rugose with a tendency to cross-striations. Fusco-ferrugineous, darker than most females of A. pluteicornis.
Oklahoma : Poteau, VII-16-'22. Numerous workers, 1 dealated female and a few larvae and pupae. Nest under a stone in the same environment as A. pluteicornis. Aphaenogaster treatae pluteicornis var. alabamensis, new variety
WORKER. Length 5-6 mm.
Differs from A. pluteicornis in the following manner : '
About half the workers have the scape of 1% times the length of the head, the rest vary to 1%. The anterior sur- face of the antenna1 lobe is usually convex with only a small shallow concavity near the low flange; in a few specimens it is deeper. The base of the epinotum varies from 2 to 2y2 times the declivity.
The head is more coarsely reticulate. Posterior surface of the node of the postpetiole finely punctate. Sparse gas- tric pubescence entirely absent.




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19341 New Forms of Aphsenogaster treatse 11 Color ferrugineous like A. pluteicornis or varying to fer- rugino-testaceous.
FEMALE. Length 8 mm.
Like A. plu.teeiorni but with these few minor differ- ences: Flange of the lobe a little higher; scape 1 1-11 the length of the head; color similar except that the frontal area is darker.
Alabama : Lookout Mt., Fort Payne, 12-VII-'29. Collected by Dr. W. S. Creighton.
Compared with A. treats, the head of the worker is not so coarsely reticulate, but the antennal lobe is similar ex- cept that the anterior flange is longer; the transverse stri- ations of the epinotum usually merge sooner into reticula- tions which disappear between the spines, but a few speci- mens approach nearer A. treatse in rugosity; the hairs are fewer and the color is always lighter.
This variety exhibits more variability within the nest than do our other forms of A. treats. The sculpture of the worker including the striations of the epinotum, and the shape of the antennal lobe are intermediate between A. plu- teicornis and A. treatas.
KEY TO THE FORMS OF APHAENOGASTER TREATAE 1. Lobe at the base of the antenna short, ?4 or 1-6 the length ....................................................................... of the scape3 .2.
Lobe longer, to VA. the length of the scape ................. 3. 2. Lobe narrow and very short, 1-6 the scape. Ferrugine- ous, head and abdomen slightly darker ................................ treat8 subsp. harnedi W. M. Wheeler (1919). ...................... Lobe $45 the scape. Dark fuscous to piceous.. treatse var. ashmeadi Emery (1895) *.
3. Lobe broadly angulate in front. Dark fuscous to piceous. tredtse subsp. wheeleri Mann (1915) .
Lobe not broadly annulate but evenly rounded. ............... 4. The lobe is measured from the point where the scape begins swell- ing to the tip of the anterior surface, nearest the antennal insertion. *Mayr (1886) first mentioned this variety but failed to name it.



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12 Psyche [March
4. Dark ferrugineous, head and abdomen ferrugino-fuscous above. Transverse epinotal striations extend to the spines .................................................. treatas Fore1 (1886) . Color lighter. Striations of epinotum not so extensive. Sculpture less rugose. Punctation on first gastric seg- ment finer ........................................................................... .5. 5. Dorsum of epinotum usually reticulate, not striate. Fer- rugineous, abdomen varying to ferrugino-testaceous.. ...... treatas subsp. pluteicornis, new subsp.
Transverse striations present on base of epinotum ...... .6. 6. Less hairy. Concavity of antennal lobe deep and flange high. Striations of epinotum very faint. Thorax light ......
f ulvous, head ferrugineous, gaster light f ulvo-f uscous treat% pluteicornis var. oklahomensis, new variety. More hairy. Concavity of antennal lobe small and flange lower. Striations of epinotum definite. Apex of post- petiole more reticulate. Coarseness of sculpture inter- mediate between A. treat8 and A. pluteicornis. Fer- .......................................
rugineous to ferrugino-testaceous
treatas pluteicornis var. alabamensis, new variety. Emery, C. 1895. Zool. Jahrb, Syst. 8: 302. Forel, A. 1886.
Ann. Soc. Ent. Belg. 30: C. R. 40.
Mann, W. M. 1915. Psyche 22: 51,l fig.
Mayr, G. 1886. Verh. z001.-bot. Ges. Wien 36: 444. Wheeler, W. M. 1919. Psyche 26: 50.




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