Wm. S. Creighton.
Descriptions of Three New North American Ants with Certain Ecological observations on Previously Described Forms.
Psyche 41:185-200, 1934.

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PSYCHE
VOL. XLI DECEMBER 1934 No. 4
DESCRIPTIONS OF THREE NEW NORTH AMERICAN ANTS WITH CERTAIN ECOLOGICAL OBSERVATIONS ON PREVIOUSLY DESCRIBED FORMS
By WILLIAM STEEL CREIGHTON
College of the City of New York
Myrmica (Manica) parasitica sp. nov.
Worker: Length ; 5 mm.
Head exclusive of the mandibles quadrate, as broad as long, the sides and occipital border feebly convex, the occi- pital angles broadly rounded. Anterior border of the cly- peus entire, angular, the portion in front of the median lobe flat, the lateral portions at either side straight but receding toward the insertions of the mandibles. Median lobe of the clypeus strongly convex in two planes, sharply separated from the large, triangular frontal area. Mandibles large and powerful, the external border rather feebly convex ex- cept near the tip where it turns inward sharply. Mastica- tory margin armed with a long, sharp and rather thin terminal tooth and a much shorter and stouter subterminal tooth; the remainder of the masticatory margin bearing 12 - 15 small teeth.
Frontal carinse short, thick, bluntly
pointed in front and rather widely separated. Antenna1 scapes short and rather thick, strongly and abruptly curved at the base; in repose the tip of the scape surpasses the occipital border by an amount less than its greatest thick- ness.
First funicular joint longer than broad and some- what broader than the adjacent joint, joints 2 - 6 gradually increasing in diameter and length, the four apical joints



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186 Psyche [December
together form a distinct club whose maximum diameter is about three times that of the preceding joints. Eyes oval, moderately convex, set at the middle of the side of the head. Thorax in profile with the promesonotum rather feebly convex, the promesonotal suture not impressed. Mesoepi- notal suture prominent but with a shallow impression on the thoracic dorsum which is principally due to the elevated anterior edge of the epinotum since the posterior face of the mesonotum slopes directly to the suture without any im- pression. Epinotum in profile with a very feebly convex basal face which passes to the shorter declivious face through a poorly marked and very wide angle. In some specimens the angle between the two faces is virtually elim- inated so that the profile of the epinotum is a single, convex, descending slope. Seen from above the promesonotum is pyriform and only a little wider than the subpentagonal epinotum. The sides of the thorax are only slightly con- stricted at the mesoepinotal suture.
Petiole seen in profile with a node which is very low, broadly and evenly convex above and without sharp transi- tions to the anterior or posterior peduncles. The ventral tooth on the anterior peduncle is very variable in character, In some specimens it is reduced to an angle, in others it has the form of a blunt, short tooth, in still others it is a very long and slender recurved spine. Dorsum of the postpetiole in profile with a long, sloping, feebly convex anterior face and a very short vertical posterior face. Ventral surface of the postpetiole in profile evenly convex. Seen from above the pe- tiole is narrow and spindle shaped with the anterior peduncle slightly thinner than the posterior peduncle. The post- petiole has the form of a truncated cone with the sides con- vex. It is a little less than twice as wide as the node of the petiole.
Gaster bulky, oval.
The sculpture of this insect, particularly that of the head, shows considerable variation. In some specimens the entire head is covered with fine, longitudinal striae. The more



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19341 Three New North American Ants 187
lateral of these curve downward under the antenna1 fossae and are carried forward to the insertion of the mandible. In such specimens the head is feebly shining with a semi- matte appearance. In other specimens the striae are almost entirely absent being represented by a few on the posterior parts of the frontal carinss and others on the side of the head between the eye and the insertion of the mandible. In such specimens the remainder of the head is highly glabrous with numerous, small piligerous punctures. The same variability is true to a lesser extent of the thoracic sculpture. In some specimens the entire thorax is covered with fine punctures which grade into longitudinal striae on the pleurae. Such specimens are feebly shining. In other specimens the whole thorax is highly glabrous, entirely without sculpture except for a few feeble lines or punctures at the base of the pleurae, The sculpture of the petiolar nodes is more constant since even in the heavily sculptured individuals, these are in large '
part glabrous. Abdomen smooth and shining with fairly numerous small piligerous punctures.
In color and pilosity the insect is more uniform. The
head is piceous with the mandibles a somewhat more brown- ish black and having a wide band of sordid yellow extending along the masticatory margin. Thoracic dorsum blackish brown, the pleurae of the pronotum clear, brownish yellow, the pleurae of the mesonotum and epinotum a clear brown which is somewhat lighter on the declivious face of the epi- notum. Petiolar nodes blackish brown. Abdomen a darker brown than the petiolar nodes but not as black as the head. The entire insect covered with rather long, slender, curved hairs which are pointed, erect and yellowish in color. These
are most abundant on the head particularly on the ventral surface where they form poorly developed gular ammochse- tss. Flexor surface of the femora with a row of stiff, erect bristles. Extensor surface of the femora, tibiae, tarsi, an- tennal scapes and the proximal half of the funiculi covered with small, fine reclinate hairs. Clubs of the funiculi pubes- cent.




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188 Psyche [December
Host : Myrmica (Manica) bradleyi Wheeler. Types in my collection and in the collection of Dr. W. M. Wheeler.
The series of workers upon which this species is based was taken on the summit of Polly Dome (elevation about 8600 feet), a small dome adjacent to Tenaya Lake on the Tioga Pass road in the upper part of Yosemite National Park, California. Because of glacial action the domes have precipitous sides planed to a high degree of smoothness. It is actually possible in certain lights to see a glaze on the surface, which resembles that of a polished terrazzo floor. Naturally, the domes themselves are not good areas for col- lecting since there is very little soil present and when any does occur it is usually in pockets of coarse gravel and sand not suitable for nest making. Despite such unfavorable conditions the nest containing the new species was found in one of these gravel pockets. When first discovered only five parasitica workers were taken since, at that time, the author had nothing with which to excavate the nest. These five workers together with a number of workers of the host, bradleyi, were taken back to camp alive and the relations between the two species observed. These were to every appearance perfectly normal, the parasitica workers taking their share of the activities and being treated as ordinary nest mates by the bradleyi workers. The following day the author returned to the nest site and excavated the entire gravel pocket, luckily a small one, down to bed rock. Eight more parasitica workers were secured but no queen of any kind was seen. I am of the opinion that she may have moved to a safer place following the initial disturbance of the nest since, due to the ease and completeness with which the gravel could be removed and sorted, it is curious that she should have been missed had she been present. The failure to find the queen is much to be regretted since her structure might have shed some light on the type of relation between the host and parasitica. As the matter stands at present it is impossible to state with certainty whether the new species



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19341 Three New North American Ants 189
is a slave maker or a temporary social parasite. In view of the fact that parasitica is smaller than bradleyi and has no mandibular specialization which might offset this disadvan- tage it seems more likely that the new species is a temporary social parasite.
Because of the close correspondence of general morpho- logical characteristics it can scarcely be doubted that para- sitica has been derived from bradleyi. It differs from brad- leyi, however, in the following respects: the epinotum is lower and less angular, the node of the petio1e.i~ lower and more rounded, the sculpture is more feeble as even the most heavily sculptured individuals of parasitica never approach the heavy sculpture characteristic of bradleyi, the thorax and petiolar nodes are black (reddish yellow in bradleyi), the hairs are stouter, more uniformly erect and considerably more numerous on the ventral surface of the head. Aphaenogaster (Attomyrma) huachucana sp. nov. Worker: Length : 4.5-7 mm.
Head exclusive of the mandibles one and one half times as long as broad, the sides subparallel in the anterior two- thirds but narrowing sharply in the posterior third. Occi- pital border flat, less than half as wide as the greatest width of the head and bordered by a narrow but very distinct re- flected flange. Clypeus moderately projecting, the anterior border sinuate with the median impression in some speci- mens broad, shallow and evenly concave, in others deeper, and more narrow with a distinct notch in the middle. Median lobe of the clypeus rather flat, ecarinate, not sharply marked off from the lateral portions and with an evenly rounded posterior border between the frontal carinse. Frontal area only slightly depressed, shining with a promin- ent median carinula. Mandibles slender, the external mar- gin straight except near the tip where it turns inward sharp- ly and is convex. Outer third of the masticatory margin armed with three prominent teeth which decrease in length from the terminal tooth inward, the remainder of the mas-



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190 Psyche [December
ticatory margin irregularly serrate. The straight inner margin of the mandible meets the masticatory margin at a sharply marked angle. Eyes oval, of moderate size and rather strongly convex with their posterior borders lying slightly in front of the middle of the side of the head. Frontal carinse prominent and subparallel, their lateral por- tions in the anterior half turned upwards so that from above this part of the carina appears narrow and welt-like. An- tennal scapes long, slender and evenly though slightly curved outward. In repose they surpass the occipital border by one-third their length. The base of the scape is strongly spatulate. Funiculus filiform, joints 1 - 7 all of about the same length and diameter and all several times longer than broad, joints 8 - 12 somewhat broader than the preceding joints and slightly increasing in diameter apically. Dorsum of the pronotum in profile feebly convex. Just
posterior to the promesonotal suture the mesonotum is abruptly elevated. This elevated portion, which is flat on top, occupies the anterior half of the mesonotum and passes to the posterior half through a short and abruptly descend- ing declivity. The posterior half of the mesonotum, which is also flat on top, is slightly if at all higher than the adja- cent portion of the epinotum from which it is separated by a narrow U-shaped impression at the mesoepinotal suture. Epinotum in profile angular, the basal face, which is straight and slopes slightly to the rear, twice as long as the almost perpendicular declivious face. The angle between the two faces is armed at either side by a short, rather blunt tooth with a very wide base. Seen from above the pronotum is subpentagonal with the lateral portions carried back past the anterior half of the mesonotum so that the latter has the appearance of being a part of the pronotum. Just behind the pronotum the sides of the mesonotum are slightly con- stricted. There is no constriction of the sides at the meso- epinotal suture other than the very shallow incision formed by the suture itself. Seen from above the dorsal face of the epinotum bears a shallow longitudinal sulcus extending



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19341 Three New North American Ants 191
backwards between the teeth. This sulcus is bordered at either side by a ridge which extends forward from the base of each tooth.
Node of the petiole in profile with a straight, sharply sloping anterior face which meets the anterior peduncle at a wide but well-marked angle. Summit of the node blunt, the posterior face slightly convex and steeply descending to the very short posterior peduncle. There is no ventral tooth on the anterior peduncle but a narrow lamella runs almost its entire length. Postpetiole in profile notably larger than the node of the petiole, its dorsum consisting of a long, slop- ing anterior face, a rounded summit and a shorter and more declivious posterior face. The ventral face of the post- petiole is straight or feebly sinuate. Seen from above the node of the petiole is subcircular, about twice as wide as the anterior peduncle and a little more than half as wide as the pyrif orm postpetiole.
Gaster rather small, oval.
Mandibles moderately shining, covered with fine and somewhat irregular longitudinal striae. Entire head, except for the frontal area and the antenna1 fossae, feebly shining or dull, coarsely reticula-rugose with the interrugal spaces finely granulose. Just above the insertion of the mandibles and on the clypeus the granulation is more feeble than else- where. In some specimens the median lobe of the clypeus lacks the granulation altogether. Antenna1 scapes finely and densely punctate. Thorax densely and rather more coarsely granulose than the head. In certain lights feeble rug= may be seen on the thorax, especially on the epinotum where they are most prominent. None of them, however, are nearly as well developed as those on the head. Petiolar nodes finely granulose. Abdomen glabrous with exceeding- ly line, piligerous punctures.
Hairs moderately numerous, rather short, coarse, golden, erect and somewhat obtuse. About equally numerous on all parts of the body. Femora with short, rather sparse, erect hairs: those on the tibias and tarsi more numerous, finer and



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192 Psyche [December
suberect or appressed. Antenna1 scapes with numerous, very fine, appressed hairs; those on the funiculi longer, stouter and suberect except on the four terminal joints where the erect hairs are replaced by pubescence. Color : head, thorax and petiolar nodes rich reddish brown to yellowish brown ; the mandibles, legs and abdomen brown- ish yellow to clear yellow.
Described from a series of ninety workers taken in Ram- sey Canyon, Huachuca Mountains, Arizona, at an elevation of 7000 feet.
Types in my collection and in the collection of Dr. W. M. Wheeler.
There can be little doubt that huachucana is closely re- lated to texana, particularly to the variety furvescens Wheeler. Despite the fact that furvescens was originally described from material taken in Ramsey and Miller Can- yons in the Huachuca Mountains I have no hesitancy in re- garding huachucana as a distinct species since the struc- tural peculiarities which it shows are reinforced by pro- nounced ecological differences. On the basis of structure the most obvious difference in the two species lies in the greater size of the new form (4.5-7 mm. in hmchucana, 4-5.5 mm. in furvescens). In addition the head of huachu- cana is of a different shape. This is due largely to the fact that the sides in the narrowed posterior third are less con- vex, the occipital border narrower and the flange which borders the latter more pronounced in the new species. The antenna1 scapes in huachucana are notably longer than those of furvescens and are strongly spatulate at the base, a fea- ture not present in the scape of the latter form. In the thorax of huachucana the anterior half of the mesonotum is more sharply set off, from the adjacent portions of the tho- rax, particularly behind where there is a definite descending posterior face not found in the thorax of furvescens. The character of the epinotal spines is quite different in the two forms. In huachucana these are short and very broad at the base so that they are more aptly regarded as angular



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19341 Three New North American Ants 193
teeth than spines. In furvescens the spines, while only slightly longer than those of huachucana, are slender throughout and not tooth-like. Finally the sculpture of huachucana is uniformly heavier than that of furvescens. The ecological differences are equally distinct. The nest from which the types of huachucana were secured was situated at the base of a rocky ledge above a very steep slope on the western side of the canyon. The arrangement was such that the nest was in the shade for the greater part of the day. The elevation, as has been already noted was 7000 feet. I have taken many colonies of furvescens both in Ram- sey and Miller Canyons. These were invariably under stones in sunny situations not far removed from the stream bottom and at elevations not exceeding 6000 feet. Finally the ac- tions of huachucana are quite different from those of fur- vescens. The insects are slow, one might almost say clumsy, in movement even when excited, a marked contrast to the active and energetic workers of furvescens. On the last day of May 1932 one of my students, Mr. Solo- mon Friedland, while collecting along the top of the Pali- sades near Englewood, N. J. had the good fortune to secure a single female belonging to the genus Anergates. At that time I considered the insect identical with the European atratulus but subsequently, through the generosity of Dr. W. M. Wheeler, I have been enabled to compare it with speci- mens of atratulus collected by Dr. Wheeler in Switzerland. This comparison has revealed a surprising number of signi- ficant differences and I now feel that the insect taken by Mr. Friedland must be regarded as a new species. Mr. Friedland's discovery is of twofold interest for it not only gives us first record of Anergates in the New World but also furnishes important data on the distributional status of the host species Tetramorium cwtum. This matter is discussed in detail at the end of the following description. Anergates friedlandi sp. nov.
Female: Length : 2.2 mm. (the gaster not expanded)



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194 Psyche [December
Differing from the female of atratulus in the following characteristics :
The single mucronate point with which the mandible is armed longer and stouter ; the convex masticatory border of the mandible very feebly serrate (smooth in atratulus). Eyes nearly circular in outline and strongly convex with rather fine facets (oval and moderately convex with coarse facets in atratulus) . Lateral ocelli small and so placed that they are hidden when the head is viewed from directly in front by the rectangular occipital crest on which they are borne (lateral ocelli larger and distinctly visible from the front in atratulzts). Antenna1 scapes slightly and evenly curved outward, gradually increasing in thickness from base to apex and in repose surpassing the occipital border by an amount equal to the greatest thickness (in atratulus the scapes are almost straight, thickest at a point about three- quarters of the distance to the apex and in repose surpassing the occipital border by an amount less than their greatest thickness). Seen from above the epaulet-like lateral por- tions of the pronotum are strongly concave, blunted behind and set off from the median portion of the pronotum by a rounded welt or ridge (in atratulus the lateral portions of the pronotum are only slightly concave, rather sharp behind and set off from the median portion of the pronotum by a sharp ridge). Scutum longer than in atratulus and with more overhang at the anterior edge. The posterior portion of the scutum is evenly depressed all the way across includ- ing the paraptera so that there is a sharp transition to the scutellum when the thorax is viewed in profile (in atratzdus the depression of the scutum is median only, the paraptera not being depressed, so that there is a sort of a shallow trough formed on the dorsum of the thorax; however in pro- file the transition between the scutum and scutellum appears less abrupt because of the elevation of the paraptera above the level of the middle of the scutum) . Scutellum narrower and much more convex than in atratulus. Epinotum seen from above with the lateral projections less prominent and



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19341 Three New North American Ants 195
more rounded than in atratulus. Seen from behind the broad longitudinal impression on the posterior face of the epinotum is broadly rounded above (narrower and rather pointed above in atratulus).
Seen in profile the node of the
petiole has a definite, short posterior face, a rounded and rather narrow summit and a long steeply sloping anterior face. Although both posterior anterior peduncles are short both are distinctly visible in profile and sharply set off from the node (in atratulus the node of the petiole is much bulkier with the dorsum broad and obtusely angular. The anterior
and posterior peduncles are so short as to be virtually in- visible when seen in profile). Postpetiole seen from above thinner from front to back than in atratulus with the an- terior edge much less convex.
The dorsum bears a shallow,
median longitudinal sulcus (entire in atratulus) . Abdomen
with a deep median sulcus as in atratulus. Sculpture very finely and evenly punctato-rugose except the very deeply notched clypeal border, the mandibles and the appendages which are shining. The sculpture is uni- formly heavier than in atratulus, particularly on the pos- terior abdominal segments where it renders the surface definitely opaque (feebly shining in atratulus) . Color: head and thorax blackish brown, gaster a some- what clearer brown, appendages dirty yellow. Wings hya- line, covered with numerous small hairs, the veins and stig- ma pale yellow.
Type in my collection.
It is much to be regretted that this interesting insect is known only from a single specimen. Following Mr. Fried- land's discovery I returned with him to the type locality, a small meadow at the side of U. S. Highway No. 9 about three miles north of Englewood, N. J. In this place there are many nests of Tetramorium ceespitum constructed in coarse, gravelly soil along the sides of a fill over which the highway runs. Although we examined a number of the nests and although, during the following spring, the site was revisited for more extensive observation, no additional specimens



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196 Psyche [December
have been taken. This is scarcely surprising in view of the rarity of the European atratulus.
As has already been mentioned the presence of Anergates in North America presents some points of peculiar interest. In the Old World Anwgates atratulus, a workerless parasite with degenerate, pupoidal males, is known to occur only in