C. T. Brues.
Phoridae Associated with Ants and Termites in Trinidad.
Psyche 39(4):134-138, 1932.

This article at Hindawi Publishing: https://doi.org/10.1155/1932/74868
CEC's scan of this article: http://psyche.entclub.org/pdf/39/39-134.pdf, 424K
This landing page: http://psyche.entclub.org/39/39-134.html

The following unprocessed text is extracted automatically from the PDF file, and is likely to be both incomplete and full of errors. Please consult the PDF file for the complete article.

Psyche
[December
PHORIDZE ASSOCIATED WITH ANTS AND TER-
MITES IN TRINIDAD1
The following notes and descriptions of Phoridse are based on a small collection secured by Dr. J. G. Myers in Trinidad, British West Indies. As Dr. Myers intends to publish observations which he has made on the biology of the several species, I am taking this opportunity to present descriptions of two forms not previously known, together with notes that extend the known distribution of two other species.
Diploneura (Dohrniphora) conspicua Borgmeier Vozes de Petropolis, vol. 17. p. 628 (1923) Arch. Mus. Nac. Rio Janeiro, vol. 25, p. 99 (1925) Two males, taken by Dr. Myers in Trinidad in company with the following species. The species was described as termitophilous by Borgmeier as his types were taken in a nest of Eutermes in Minas Geraes, B'razil. This species resembles the North American D. incisuralis for which I mistook it at first glance, but the bristles out- side the seam on the hind tibia lie much nearer to the hair- seam.
Diploneura (Dohrniphora) myersi sp. nov. 2. Length 1.6 mm. Body black; antennae dark brown; palpi somewhat lighter brown ; proboscis honey-yellow ; legs dull brownish yellow, their coxse almost black, except the front ones which are brownish; wings hyaline, with piceous venation. Front shining, slightly higher than broad ; supra- antenna1 bristles inserted close together, strongly diver-
^From the Entomological Laboratory, Harvard University)



================================================================================

19321 Phoridse Associated with Ants and Termites 135 gent; lower row of bristles (antial and first lateral bristles) forming a row strongly curved downward medially, the me- dian ones twice as far from one another as from the lateral bristle; middle row nearly straight and equidistant; ocellar tubercle scarcely evident. Cheeks with a bristle at the lower angle of the eye and one below at the oral margin. An- tennse small, oval ; arista pubescent. Palpi moderate, each with five bristles at apex. Proboscis rod-like, as long as the head height beyond the basal bend. Eyes uniformly pubes- cent, postocular cilia rather short. Mesonotum shining; scu- tellum twice as wide as long, with a pair of bristles at each side, the anterior one much smaller and almost hair like. Hairs of mesopleura reduced to a small group near the spiracle; one large macrochseta on the propleura below the spiracle. Abdomen with five chitinized tergites, the second lengthened and without bristly hairs at the sides; fifth more or less subtriangular or narrowly trapezoidal; following segments membranous. Front tibia with a series of four bristles on the fore side, one at the basal fourth, one at middle, one at apical fourth and one just beyond. Middle tibia with a pair of bristles externally near base and a hair-seam extending to the middle, beyond which is an area of six imbricated transverse rows of minute bristles. Hind tibia with a complete dorsal hair-seam and a row of bristles just next to it inwardly. Costal vein extending slightly beyond the middle of the wing; costal divisions 25 :7.5 :3, the first therefore nearly two and one half times longer than the other two together; costal cilia very short and closely placed ; first vein distinctly thickened beyond the middle and the third from near the middle; second vein leaving the third at a very acute angle so that the cell formed is more than twice as long as wide on the costa with the veins bounding its sides very thin; one small bristle on the third vein at its base; fourth vein originating at the base of the second, gently curved at base and nearly straight beyond; seventh vein weak, but clearly defined. Halteres black.
Type: Trinidad, B. W. I., November 25, 1928; one speci- men taken by Dr. J. G. Myers, hovering over a termitarium of Eutermes during a raid made by ants on the termites.



================================================================================

136 Psyche [December
It would seem probable that the species is termitophilous as such is known to be the case among some other species of the genus.
In spite of the numerous species, several of which are termitophilous, that have been described from the Ameri- can tropics, this species is undoubtedly undescribed. From several forms that are similar, it is distinguished as fol- lows: from D. knabi Malloch by the shorter first section of the costa which is 2% times as long as the other together, instead of 5 times, and by the nearly straight middle trans- verse row of frontal bristles; from D. obscuriventris Borgm. by its entirely black color ; from D. intrusa Borgm. by the presence of 5 abdominal tergites and the black hal- teres (although there is a disagreement here between the original description and a subsequent key to species) ; from D. anterodorsalis Schm. by the longer first section of the costa.
Megaselia juli Brues
Three specimens collected in the act of attacking and ovipositing in a large millipede and one later reared from the same host; Trinidad, Dec. 19, 1928 and Jan. 4, 1929. These specimens seem to be indistinguishable from the North American Megaselia (Aphiochseta) juli Brues in spite of the widely separated localities.
A South American spe-
cies, M. mucronata Borgrneier from Petropolis near Rio de Janiero is very similar, but differs in its much longer ovi- positor and more nearly equal first and second constal di- visions in the wing.
The ovipositor shows the same striation on both the api- cal and basal sections as Borgmeier has described and fig- ured for M. mucronata (Arch. Mus. Nac. Rio de Janeiro, vol. 35, 142 (1925).
In both M. juli and M. mucronata the mesopleura has one strong macrochseta in addition to minute hairs. An Euro- pean species M. styloprocta Schmitz has the body black and the mesopleural hairs all minute, although otherwise very similar.
Cremersia Schmitz
There is a species of this peculiar genus in the collection.



================================================================================

19321 Phoridas Associated with Ants and Termites 137 The female possesses a most remarkable asymetrical ovi- positor that shows such striking similarity to the hypopy- gium of the males of certain other Diptera that specimens of this sex were first mistaken for males. Borgmeier has, however, more recently found the male (Arch. Biol. Silo Paulo, vol. 1, 1928) and thus shown conclusively that this organ is in fact an ovipositor of very unique type. Cremersia minor sp. nov.
9. Length 1.4 mm., including ovipositor. Black or pi- ceous, lighter on the mesonotum, pleurae and legs. Front, abdomen above and ovipositor black ; antennae and mesono- turn fuscous ; palpi and legs testaceous, the pleurae consider- ably stained with brown ; halteres piceous, with paler stalk. Wings hyaline, heavy veins piceous, light ones strongly colored, but very delicate. Lowest pair of frontal bristles separated by one-fourth the width of the front, stout and but little divergent; second row of two large bristles set very close to the eyes; third row of four equidistant, curved downward medially, placed high on the front, with the lat- eral bristles but little below the level of the lower ocellus. Antennae small, bluntly oval, the arista short, stout and scarcely pubescent. Palpi very small, with four weak bris- tles at the tip; cheeks each with two rather strong bristles below the lower corner of the eye. Mesonotum long and narrow, with one pair of small dorsocentral bristles placed close to the hind margin; surface clothed with conspicuous fine hairs, and side margins with several conspicuous bristles just before the base of the wing as well as a large one on the scapula. Scutellum about semi-circular, with one pair of very short bristles and an extremely minute bristle in front of each of these. Propleura with two bristles next to the spiracle and another near the insertion of the fore coxa. Mesopleurae entirely bare. Second segment of abdomen lengthened, the three following subequal, not greatly narrowed. Fourth tergite with a subapical series of delicate bristles, growing stronger laterally; fifth tergite on the margin with a series of four large bristles on each side and a series of about four small, delicate ones between. Sixth tergite much narrower than the fifth, convex and



================================================================================

138 Psyche [ December
rounded at apex, with two cross rows each of five long, curved bristles, the anterior row on the right side and me- dially somewhat overlapping the posterior row (which is on the left side) as the anterior row extends well to the left of the median line; all these bristles curved toward the righthand side. Fifth sternite with a close series of about six stout bristles. Legs long and slender; front tarsi not modified in any way. Front tarsi with the first joint almost as long as the tibia; second and fifth joints each half as long as the first; fourth one-fourth shorter. Hind tibia with a dorsal hair-seam and a series of very minute setulse just internal to this, these setulse not much larger than the hairs that clothe the inner surface of the tibia; tibia at apex with one small bristle inside the seam; hind femur simple, without long hairs below. Ovipositor of the usual hypopygium-like form; shining black in color with a long finger-like process above that curves to the left and is pro- vided near its base with two transverse bristle-like spines that extend horizontally to the left; below with a short pro- cess apically, terminating in a twisted hook. Wing similar to that figured by Borgrneier for C. pilosa. Costal vein ex- tending to slightly beyond the basal third of the wing its bristles long; first section more than twice as long as the second and third together; third not quite half as long as the second; fourth vein entering the margin at tip of the wing; fifth lying very close to the fourth. One female collected by Dr. J. G. Myers in Trinidad, B. W. I., November 25, 1928, "hovering constantly close over the backs of ants engaged in raiding a termitarium (Eutermes)." So far as is known the numerous South American species of this genus are ecitophiles. In Borgmeier's key to the Brazilian species of this genus (Arch. Inst. Biol., SSo Paulo, vol. 1, p. 161, 1928) this spe- cies will run to C. br(~si1iensis from which it differs in the bristling of the terminal abdominal segments, especially in the very stout, straight bristles on the sixth sternite. It is also a much smaller species.




================================================================================