Charles T. Brues.
Some Myrmecophilous Phoridæ from the Neotropical Region.
Psyche 32:303-312, 1925.

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19251 Myrmecophibus Phoridm from the Neotropical Region 303 SOME MYRMECOPHILOUS PHORIDLE FROM THE NEO- TROPICAL REGION.1
BY CHARLES T. BRUES.
The several interesting flies described in the present paper have been sent to me through the kindness of Dr. Wm. M. Mann. During the course of his myrmecological excursions he never fails to obtain series of myrmecophilous insects and among these there are usually a few forms of wingless or subapterous Phoridse. Those obtained by him recently in Mexico and Central America include several remarkable species taken in the nests of a number of ants, mainly with Eciton and Pheidole. The types of the new species are deposited in the United States National Museum in Washington.
Eci tomyia Brues.
American Natural., vol. 35, p. 347 (1901) Since I described this genus nearly twenty-five years ago, the type pecies, E. wheeleri remained its only representative until 1923 when Borgmeier added two species from Brazil. The name Ecitomyia was originally applied as the Texan E. wheeleri was found to be regularly associated with Eciton ccecum. Borg- meier's two species were, however, found associated with Sole- nopsis scevissima var. picea and I now have a fourth species taken in Costa Rica with Pheidole.
It is evident therefore that the genus is by no means res- tricted to the driver ants although there can be no doubt that E. wheeleri is a true ecitophile and that it is restricted at least in Texas to association with Eciton ccecum. I have taken it many times and in considerable numbers, but never encountered it with any of the other species of Eciton that are common in that region.
Ecitomyia is closely similar to Ecitophora Schmitz and in error I once referred the type species to Ecitomyia (Psyche, vol. lcontribution from the Entomological Laboratory of the Bussey Institu- tion, Harvard University, No. 253.




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304 Psyche [December
30, p. 21, February 1923) although later in the same year I have correctly referred it to Ecitophora (Zoologica, New York, vol. 3, p. 439; (October 1923). As Schmitz has since pointed out on numerous occasions Ecitophora possesses well developed ocelli while these are entirely lacking in Ecitomyi%.l The Costa Rican species is most closely related to its nor- thern congener, E. wheeleri Brues, but differs in chaetotoxy and considering its different host relations must I think be regarded as a distinct species.
Ecjtomyia manni sp. nov.
9 . Length 0.7-0.8 mm. Very similar to E. wheeleri. Eyes decidedly smaller in diameter than the third antenna1 joint.
Post-antenna1 bristles large and strong, as long as the tennal joint; lateral brist,les of the second and third row very weak, rn-uch smaller than the median ones. Lateral thoracic
bristle nearly as long as the dorsum of thorax (.075 mm. a,s compared to .063 mm. in E. wheeleri).
Wing as long as the
dorsum, its bristles about 25p in length (compared to 13p in E. wheeleri) .
Second abdominal tergite not noticeably narrowed basally.
Type and two paratypes from Estrella Valley, Costa Rica (W. M. Mann). These were taken by Dr. Mann in April, 1924 in a nest of Pheidole.
l1n his original description Schmitz speaks of the type of Ecitophora having been bleached in the preservative fluid and of the extreme difficulty in detecting the bristles of the front. In Psyche (I. c.) I have suggested that possibly Schmitz might have mistaken the insertions of bristles for the ocelli. This remark was certainly not intended as any criticism of this author's uni- formly painstaking work on these extremely small insects. The writer ap- preciates only too well the difficulties of studying them when imperfectly preserved or when injured before or after preservation or even when the mounting does not allow one to turn the specimen into the proper position to determine minute characters. On finding finely preserved specimens agreeing almost exactly with Schmitz's description of Ecitophora comes, but without ocelli, I naturally supposed that the ocelli described were really the points where bristles had been inserted. Father Schmitz has however assured me that the condition of the type allows three ocelli to be distinguished. I wish therefore to make an apology for my seemingly very hasty remark which as indicated above was in no way intended to suggest any carelessness on the part of a most accurate observer. Further work also attests the accuracy of Schmitz's first observation as additional specimens of E. comes have since been collected and other species discovered.




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19251 Myrmecophilous Phoridce from the Neotropical Region 305 As indicated this species differs from E. wheeleri by the much longer lateral thoracic bristle and wing bristles and in the form of the second abdominal tergite.
In addition to the above I have another most remarkable species which is referred provisionally at least to Ecitomyia. It certainly cannot be placed in any other genus so far described and differs also very conspicuously from the other very closey allied species of this genus in possessing a number of enormously enlarged bristles on the abdomen.
These form transverse rows
at each side of the tergit'es which are formed as in Ecitomyia as are also the head, thorax and wings.
As I suspect that inter-
mediate forms may be discovered it does not seem wise to make this the type of a new monotypic genus.
Ecitomyia spinosa sp. nov. (Fig. 1)
9. Length 1.5-1.7 mm. Head, thorax and abdominal plates and spots yellowish brown; abdomen pale yellowish white; legs brownish yellow ; antennae pale yellow ; wings dark, almost black except at base. Head somewhat more than twice as broad as long, the anterior margin of the front rounded, more sharply so at the middle. Mouthparts very small, retracted within the oral cavity which is sharply carinate anteriorly. Eyes small, oval, about one-fourth as long as the head-height; ocelli entirely absent. Antennae ovate, quite distinctly contracted at the apex; arista long, strongly pubescent, as long as the head-height. Four strong proclinate antenna1 bristles medially at the anterior mar- gin of the front, the upper pair longer and set further apart; middle frontal row represented only by one lateral bristle near the eye; upper row of four about equally spaced. Thorax oval, twice as wide as long, with a strong bristle at each side and four across the disk; also a pair of smaller ones near the middle behind and another toward the side between the lateral pair of the transverse row. Wings reduced to small band-shaped pads as long as the dorsum of the thorax; the upper surface is convex, the tip more or less pointed and the surface strongly bristly, some of the bristles almost as long as the wing. Abdomen broadly ovate, the four apical segments forming a tube of rather



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306 Psyche [December
narrow diameter which is distinctly turned upwards in fully developed specimens; one stenogastric individual has the ab- domen much smaller. Dorsal plat'es of the second to fifth segment present; the second large, with four strong bristles along the hind margin; the others much smaller, each with a pair of bristles Fig. 1.
Ecilomyia spinosa sp. nov., female. A, dorsal view; B, ventral view.



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19251 Myrmecophilous Phoridce from the Neotropical Region 307 placed behind close to the lateral angles. Fifth segment with
a gland opening which lies within a quadrangular chitinous rim that arises from the front margin of the fifth plate. Abdomen bearing twenty-four greatly enlarged marcochsetae, each about as long as the hind tibia. These are arranged in four transverse rows, three bristles at each side of each abdominal plate. Where each is inserted to the pale abdominal membrane there is a small rounded dark brown spot. These stout, intensely black bristles are very conspicuous and together with the blackish wing pads give the insect a most extraordinary appearance. Legs rather long and not very stout; the hind femora rather noticeably com- pressed.
Type and three paratypes from Huascato, Jalisco, Mexico (W. M. Mann). These were taken in a nest of Pheidole sp. Another specimen from San Diego de Cocula, Jalisco, Mexico (W. M. Mann) was taken with Eciton.
The small wings are unusually dark and heavily chitinized, but are evidently very weakly attached to the body as one spe- cimen has lost both wings and two others had only one wing re- maining attached when I received them.
Ecitophora costarkensis sp. nov.
8'. Length with abdomen well extruded 1 .6 mm. ; without tubular apex of abdomen, 1.3 mm. Length of wing 0.30 mm.; of dorsum of thorax 0.24. Front with 14 bristles comprising four strong post-antenna1 ones of which the upper ones are twice as far apart as the lower, four in the lower frontal row disposed as a pair close to each eye with the out,er bristle well above the inner one, six in an upper row close to the vertex with the lateral bristle near the eye margin. Head covered with coarse, well sep- arated hairs, very conspicuous on the sides below the eyes; cheek with a strong downwardly directed bristle. Palpi rather slender, each with six strong bristles. Eye elongate oval, longer than the third antenna1 joint, but only about two-thirds as wide; ocelli present,, well developed. Third joint of antenna subovate, as long as broad; arista distinctly longer than the head-height. Thorax above with eight bristles, one at each



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308 Psyche [December
anterior angle, one lateral one just behind the middle and four forming a dorsal line behind the middle with its lateral bristle quite close to the one in front of it; in addition there are two shorter bristles near the median line close to the posterior margin which are undoubtedly homologous to the scutellar bristles al- though there is no trace of a scutellum. Wing narrow, strap- .
shaped, strongly bent near the middle, its outer edge clothed with fine bristly hairs at the base and small bristles apically, and in addition with a series of five longer bristles each about half as long as the wing. Abdomen with the second tergite chitinized, one-third longer than wide, the base four-fifths as broad as the apex; anterior angles rounded, posterior ones sharply angulate; with the usual hairs and row of minute apical bristles. Third tergit<e absent; fourth very small, crescentic, with four marginal bristles; fifth a minute band with a circular ring behind enclosing the gland opening, with two minute bristles at tip. Posterior margin of second to fifth segments with a row of minute bristles; sixth segment bristly medially and at tip. Legs rather stout, the hind metatarsi unusually stout.
Typc from Hamburg, Farm, Sen Jose, Costa Rica (F. Never- mann) taken with Eciton sp.
This species agrees closely with the previously described species. From E. parya Schm. it may be distinguished by the complete absence of the third tergite and longer wing bristles; from E. bruchi Schm. by the presence of 14 frontal bristles; from E. comes Schm. by the presence of eight dorsal thoracic bristles and a greater number of wing bristles; and from E. collegians Borgm. and E. cequalis Borgm. also by the eight thoracic bri~t~les. Heretofore no species of this genus have been reported outside of the South American continent..
Ecituncula Schmit z
Tijdschr. v. Entoin., vol. 66, p. LXXIX (1923) Schmitz, Pub. No. 4, Mus. Nat. Rio de Janeiro, p. 26 (1924). A species probably referable to this genus was t'aken by Dr. Mann in the nest of Pheidole in Mexico. It differs greaty from the type and only described species of Ecituncula in having



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19251 Myrmecophilous Phoridce from the Neotropical Region 309 the abdomen beset with a large number of bristly hairs arranged in transverse rows. It differs also in having a lateral pair of well developed frontal bristles in addition to those present in the type species and also has the full number of mesonot'al bristles. There are no wings in either of the two specimens, but as the wings of some of these forms are very readily deciduous, it is impossible to be positive that wings may not have been present. In the species described on an earlier page as Ecitomyia spinosa some specimens had lost either one or both wings. As the at- tachment of the veistigial wing, in t8his form at least, appears to be very feeble and as microscopical examination does not readily disclose any indication of a rupt,ure of the cuticle, I cannot feel perfectly satisfied on this point.
Ecituncula setosa sp. nov. (Fig. 2).
9 . Length 1.0-1.3 nim., dependent upon the stenogastric or physogastric condition. Head, metathorax and basal ab- dominal plate dark brownish; antennae and legs pale t,estaceous; abdominal membrane pale yellowish white. Head, seen from above, more than twice as wide as long; rounded at the sides and sharply rounded medially in front. Eyes small, about half the diameter of the antenna, wit>h contiguous facets. Four post- antenna1 bristles near the anterior margin of the front, the upper pair farther apart than the lower one; middle frontal row con- sisting of four long bristles forming a pair rather close to each eye, the inner one of each pair much higher than the lateral one; ocellar row of four, the median ones nearer to each other than to the adjacent lateral one. Ocelli absent. Palpi of the usual form, with about five strong bristles along the margin. Antennse oval, slightly acute apically, very densely pubescent; arista very short and thick, composed of three very distinct segments. Meso- thorax about twice as broad as long, the sides rounded, slightly angulate just in front of the middle; with a large stout bristle close to each lateral angle and a transverse series of six across the middle of the disc. No trace of wings, although there is a small impression at each posterior angle of the mesothorax at the point where strap-shaped wings are attached in forms where



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310 ' Psyche [December
these are present. Metathorax forming a narrow band lying in a basal emargination of the abdomen. Abdomen in the fully de- veloped physogastric form ovate, at least twke as broad as the head and thorax, widest near the middle of the second segment; dorsum with only one chitinized plate, that of the second seg- ment and a chitinized ring surrounding the gland opening of the fifth segment; the second plate is about as long as broad at Fig 2.
Ecitnncda setosa so. nov., female.
apex which is one-half broader than t,he base. Abdomen very
bristly, the bristles arranged in about eight transverse rows very clearly aligned except near the narrow apex of the abdomen; the bristles are longer and stouter at the side of each row and the lateral bristle is in each case much the largest. Legs rather short and stout, with the usual minute bristling:. Type and one paratype from San Diego Cocula, Jalisco, Mexico, with Pheidole sp. (W. M. Mann).
Puliciphora myrmecophila sp. nov. (Fig. 3). 9 . Length 1.0 mm.- Head and thorax brownish yellow, darker above; dorsal abdominal plates piceous, the abdominal



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19251 Myrmecophilous Phoridce from the Neotropical Region 3 11 membrane yellowish white; antennae, palpi and legs pale brown- ish yellow. Four strong postantennal bristles, the upper pair nearly twice as far apart as the lower; other frontal bristles very weak except the two in the upper row between the ocelli which are long and stout; the lateral bristle of this row and the one within the eye-margin very small and scarcely differentiated from the frontal hairs which are unusually large. Three stout bristles below each eye above the oral margin. Proboscis stout, oval, nearly as long as the head height. Third joint of antennae rounded, the arista rather strongly pubescent, one-fourth longer Fig. 3.
Puliciphora myrmecophila, female, dorsal view of abdomen. than the head height. Eye as large as the antenna; composed of about twenty-five facets. Thorax slightly wider than long, with a transverse series of six bristles behind, the median pair close to the hind margin and farther apart than their distance from the adjacent ones which are placed farther forward; lateral bristle placed at the posterior third of the mesonoturn. Abdomen with six dorsal plates; first unusually long, the lengths of the plates 25:45:29 :25:16:8. There is no distinct slit in the fifth segment for the opening of the gland but a transverse crescentic or almost semicircular clear area indicates its position. That this area represents the fifth segment is evident from the furcula (apodeme) of the sixth segment which extends forwards at this point (see fig. 3) although there is no segmentation of the sides of the ab- domen to mark off the fifth segment. Sixth and also a small



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312 Psyche [December
seventh tergite present. Legs rather slender, the four posterior tibiae each with a single small apical spur; hind metatarsus with six transverse rows of bristles. The abdominal membrane is covered with conspicuous dark chitinized specks, each bearing a minute bristle; these extend also over the entire venter but are absent on the sides except on the last two segments. Type and one paratype from Ototonilco, Jalisco, Mexico (W. M. Mann), taken in a nest of a species of Pheidole. The absence of a distinct fifth tergite and the well developed sixth and seventh tergites seem to distinguish this form from any others described although to judge from his figure, it is possible that P. pusillima de Meijere may have a similar conformation of the abdominal plates. De Meijere indicates however only five tergites with a space between the fourth and fifth. In my spe- cimens of the present form the apodemes described by Schmitz as arising from the sixth segment are very clearly to be seen arising from the anterior margin of the penultimate tergite. Under a very high power (oil-immersion) it is seen that they are attached to a small median plate more or less separate from the one I have called the sixth, but I think the larger part must be tche sixth and not a seventh tergite.
Chonocephalus jamaicensis Brues.
There is a single female of a species of Chonocephalus from Costa Rica bearing the label "with Coptotermes niger Snyder (Coll. F. Nevermann). After a very careful examination, I cannot distinguish it from C. ja,maicensis Bruesl. In Jamaica, at least, this species is not associated with either ants or termites and such seems usually to be the case with members of this genus although Borgmeier2 has described C. ecitophilus taken with Eciton in Brazil. I am therefore satisfied that the association of the present specimens with termites is accidental. lPsyche, vol. 22, p. 102; 1915.
2Deutsch. Ver. Wiss. u. Kunst. S5o Paulo, Jahrg. 3, p. 145; 1923.



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