Article beginning on page 337.
Psyche 5:337-342, 1888.

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PSYCHE.
DESCRIPTIONS OF SOME NEW NORTH AMERICAN
DOLICHOPODIDAE.
BY WILLIAM M. WHEELER, MILWAUKEE, \VIS.
Since the publication in 1864 of
Loew's admirable Monograph of the
North American DoZicho$odidae, very
little work has been done 011 these inter- esting diptera. Baron v. Osten Sacken
in his Western diptera," published in
1877, described from California nine
new species, belonging to the genera
Hygroceleuthus, DoZichopus, Tachy-
ffechs, LiancaZzts, SceZZus and Poly-
medon. The last is a new and very
peculiar genus. Mik, in 1878 (Ver-
hand. d. zoolog. bot. gesell. p. 617-
632) described one new North Ameri-
can species for which he erected the
genus Hyfocharassus. More recently,
in 1888, Bigot (Bull. soc. ent. France
XXIX, XXX) has described eight new
species from Hayti, Mexico, North
Carolina and California, representing
several new genera.
Barring these contributions, our
knowledge of the North American
DoZicho$odidae has made no advance
since Loew's time. This is not to be
attributed to inattention on the part of living dipterologists, but rather to the thoroughness of Loew's work. From
a taxonomic standpoint little is left to the 'c+ovoi. besides the filling out of
the unavoidable gaps in the work of the
master entomologist.
Like other students of our diptera,
who have given some attention to the
BoZicho$odidae, I can add very little to Loew's work. With three exceptions
the species here described fall naturally into genera defined and adopted by
Loew. For these three exceptions I
have erected two new genera, Peloro-
9eodes and A/hun/otinzus, based, I be-
lieve, on sufficiently distinctive charac- ters. The former, including as yet only
one species, P. saZax, is allied to Rha- å´phiurn the latter, to which I assign two species, A. wiZZ/s/oni and A. frater-
culus, is allied to Chysotz'mus. Pel-
oropeodes is interesting as forming a
link between those higher forms, which,
like Dolicho$us, have large disengaged
hypopygia and the genera like Rha-
$hiurn, Porfhyrofs and its allies, which have the third antenna1 joint elongated, tapering, with apical arista, and the
hypopygium small and more or less
imbedded. Aphantotimus appears to




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form a similar link between the Do&
chojus-like forms and the species of the genus Chrysof/mus.
DOLICHOPUS ALBICILIATUS, Loew. 8.
Length 6 mm. ; length of wing 4, 5 mm.
Face narrow, covered with silvery white
dust. Antennae black, third joint small, rounded anteriorly. Front dark bluish
green ; cilia of the superior orbit black, those of the inferior orbit pale yellow. Thoracic dorsutn shining dark metallic green ; pleurae black, anteriorly, with greenish bronze reflec- tion, posteriorly dusted with white. Tegu- lae with black cilia. Scutellum dark green with violet reflection. Abdomen dark bluish green, the terga. of the first and second seg- ments with violet reflection ; incisures broad- ly black; venter black, powdered with white dust; hypopygium black, opaque, with pale dull yellow lamellae of subtriangular outline, apical margin rather evenly crenulate, broad- ly bordered with black and fringed with deli- cate long hairs; penis and other appendages pale yellow, Coxae opaque black, tipped
with yellow; the anterior pairs with several curved black bristles on their fore faces; all the femora black, with metallic green re- flection, broadly tipped with yellow; anterior tibiae pale yellow, with black setae. which are conspicuously long on the fore pair; ante- rior tarsi pale yellow, blackened from the tip of the first joint; hind femora ciliated with long and delicate hairs on their inner faces; hind tibiae slightly incrassated, pale yellow with their apical third black ; hind tarsi black, the metatarsal joint slightly incras- sated. Halteres dull yellow. Wings gray- ish hyaline ; veins black; the juncture of the first logitudinal vein with the costa thickened, though not to the degree observed in the males of some allied species; last section of the fourth vein appearing considerably
steeper than in the $ and meeting the costa nearer the end of the third vein.
HABITAT : Wisconsin.
Only the female of D. albiciliatus
was known to Loew. In view of the
fact that the male is from a taxonomic
standpoint by far the more important
sex in the study of the Dolicho$o&dae,
I have in this as
in the case of a few of
the other species, of which the males
were unknown to Loew, inserted a
description.
DOLICHOPUS INCONGRUUS, n. sp. 8.
Length 5 mm. ; length of wing 4.75 mm.
Dark metallic green. Palpi black; face
narrow, silvery white. Antennae large,
entirely black, the two basal joints short and small ; third joint unusually large, flattened, suboval, dorsal con tour straight with the arista inserted near its middle, ventral contour evenly rounded. Pubescence of the eyes distinct, white.
Cilia of both the
superior and inferior orbits black. Front and thoracic dorsimi deep metallic green, the latter with a cupreous reflection in the median line and on its hun~eral edges;
pleurae black, dusted with white. Tegulae yellow with yellow cilia.
Scutellum and ab-
domen deep metallic green varied with
cupreous; venter black, covered with white dust ; hypopygium large, swollen, black
with metallic green reflection and white dust; penis and internal appendages yellow ; lamellae small, elongate oval, tapering but rounded at their tips, edges black, scarcely jagged and fringed with short and weak
black hairs. Coxae black, and like the
pleurae, dusted with white; apical third of the anterior face of the fore coxae and tips of the posterior coxae yellow; the usual tufts of black hairs on the anterior faces of the fore and median pairs and a single back- ward directed seta on the lateral face of the hind coxa. Fore legs yellow ; the basal two- thirds of the femora black; tarsi about as



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long as the fore tibiae, plain, being neither attenuated nor infuscated. Median legs pale yellow throughout; femora with preapica.1 bristle. Hind femur eciliate, black, with yellow tip and with preapical bristle; tibia setose, not incrassated, with its anterior face and tip black, its base and posterior face yellow the latter with five pronlinent setae; tarsi entirely black. Halteres yellow. Wings gray, hyaline ; the venation resembling that of other dark-legged species of DoIic//~us; costa presenting a short but distinct swelling at the juncture of the first longitudinal vein; this swelling does not interrupt the straight outer contour of the costa but bulges out dis- tinctly on its inner edge; veins black pos- terior cross-vein forming right angles with the fifth longitudinal vein. The base of the wingis rather acute.
HABITAT : Milwaukee Co., Wis.
This species is to be admitted to the
group comprising Loew's D. $achy-
cnemus and brevipennis^ both of which
are characterized by having the cilia of the inferior orbit black, while the pre- vailing color of the legs is yellow. The male incongruus differs from the males
of both of Loew's species in having the
tegular cilia yellow, in the coloration of the legs, in having the fore tarsi plain and the hind femora eciliate. . There
are several other differences but these
will suffice to separate the species.
A male agreeing closely with Loew's
description of this species was sent me
from Mass. by Mr. S. Henshaw. The
hypopygial larnellae were so nearly de-
stroyed in the single specimen from
which Loew's description was taken
that he could only affirm that they were yellow. In my specimen they are well
preserved and very unlike the hypopy-
gial larnellae of other species of Doli- chopus known to me.
They are rather
large, entirely pale yellow, of a rhom-
boidal shape, and have their somewhat
swollen edges smooth and entire, not
jagged as in other species. The upper -
(or when the hypopygium is flexed
back in line with the abdomen, the
under) edge is slightly twisted, folded
in and fringed with delicate black hairs, which I take to be the homolog~ies of
the ragged fringe so characteristic of
most species.
DOLICHOPUS FLAGELLITENEXS, 11. sp. 3.
Length 5 mm. ; length of wing 4. j mm.
Rather dark metallic green.
Palpi yellow,
black at their tips. Face about the normal breadth for a male, overlaid with yellowish gray dust. Antennae of medium size; first joint yellow, with the usual black hairs con- spicuous; second joint yellow with its dor- sal half black; third joint small, rounded, black, blunt anteriorly; arista rather robust, blackish with short white pubescence.
Front metallic green with coppery reflection ; cilia of the inferior orbit short, yellow. Thoracic doi-sum dusted in front with white, the median line coppery; humeral callosity concolorous with the dorsum. Scutelkim
with a large coppery spot on each side of the median line. Pleurae dull metallic green dusted with white posteriorly. Tegulae with black cilia. Abdomen with coppery reflec- tion ; venter overlaid with white dust : hypo- pygium black, lamellae of moderate size, suboblong, white, upper edge infuscated and fringed with rather weak black hairs. Fore coxae yellow, blackened only at their bases ; beset in front with several long and conspic- uous black setae ; posterior coxae concolorous



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with the pleurae, their tips only yellow; the median pair fringed, like the fore pair, with black setae. Legs yellow ; fore tibiae pro- vided with a few prominent black setae;
tarsi 14 times as long as the tibiae ; first and second joints attenuated, stalk-like, both together equalling the tibiae in length; sec- ond joint thinner than the first and about as long ; third and fourth joints of about equal length, both together about half as long as the second joint. The fourth joint, which is yellow at its extreme base, but otherwise black. is broader than the third joint; fifth joint flattened out into a 'large oval black disk, densely fringed on its anterior edge with short black hairs and provided with a small and inconspicuous tuft of silvery hairs near the insertion of the claws. Median
femur with a preapical bristle; tibia with rather prominent black spines ; tarsus plain, blackened from the tip of the first joint. Hind femora eciliate, with preapical bristle; hind tibiae distinctly incrassated ; apical half black; setae prominent; a rather dense cov- ering of shorter black hairs, especially on the inner face, which presents a smooth streak longitudinally coextensive with the black coloring; hind tarsi black, metatarsal joint a little thickened; its extreme base yellow. Halteres yellow. Wings more brownish than grayish hyaline ; veins dark brown ; costa slightly thickened where it meets the first longitudinal vein ; fourth vein presenting the usual double flexure ; posterior cross- vein meeting the fifth longitudinal vein at right angles.
HABITAT : Milwaukee CO., W~S.
This species is related to several
North American dolichopodes. In gen-
eral appearance it approaches D. ba-
//ZIz'$er, Loew, from which- it may,
however, be very readily distinguished
by the color of the antennae, tegular
cilia and hind femora. The dilated
fifth tarsal joint of the fore foot is in my species deep velvety black, whereas in
batillzyer it is more brownish and cov-
ered with minute silky hairs which
make it resemble a silver reflector when viewed from the proper angle.
In the color of its hind tarsi D. pal-
aestricus, Loew, approaches flayel&
tenens more closely than does batilhfer. Loew's species, however, has entirely
black antennae, pale tegular cilia and
entirely yellow hind tibiae. Both Mil-
lifer and $aZaes/rz'cus have the hind
femora ciliated, the former more abun-
dantly, the latter less so, while the
hind femora ofJageZZi/enens are eciliate. DOLICHOPUS HESSHAWI, n. sp. f.
Length 5-5.5 mm. ; Length of wing 5-
5.5mn1.
Metallic green, changing to coppery and
violet.
Palpi pale, blackened at their ends.
Face rather narrow, overlaid with ochre-yel- low dust. Antennae small, reddish yellow; basal joint smooth on its under surface, the black hairs on its upper surface, as also those on the second joint, stiff and rather conspic- uous; third joint small, smooth,
not much
flattened, ending in a short, acute point; api- cal half black; arista robust. Front metallic violet, moderately shining; cilia of the supe- rior orbit black, those of the inferior orbit yel- low. Thoracic dorsum resplendent coppery green, passing into violet on the scutellum ; pleurae metallic green, subdued by a layer of silver gray dust. Cilia of the tegulae black. Abdomen with resplendent cupreous reflection especially in the median dorsal line ; hypopy- gium black with dull metallic green base, and pale yellow lamellae and internal appendages ; the former are quite large and shaped like isos- celes triangles with rounded angles ; the two sides forming tho apical angle by which the lamella is attached are not infuscated though fringed with a few short and weak yellow hairs; the two other angles are narrowly



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May iS9.J JTaf ^J-m. 941
blackened and fringed with rather coarse black bristles as is also the side included by them. Fore coxae pale yellow, their extreme base, only, blackened ; posterior coxae for the most part concolorous with the pleurae and cov- ered with the same silver-gray dust; on their tips, however, this dark coloring passes into pale yellow. The anterior coxaeare covered on their fore faces with black hairs, some of which are long and conspicuous, though a greater number are short and evenly distrib- uted.
Legs pale yellow; apical sixth of fore tibia somewhat incrassated, blackened and pro- vided with several prominent flattened black hairs on its anterior face. These hairs are so graduated in length as to make the tip of the tibia seem more incrassated than it really is. Fore tarsus 11 times as long as the fore tibia ; first joint about + as long as the tibia, black- ened at its tip, its base on the anterior side bared of the small black hairs which cover the joint; hence, at first sight, this joint seems to have a pale spot where it joins the tibia; second joint somewhat longer than the third, second and third together about equal to the first joint; fourth joint about a third as long as the preceding joint, black, except at its base, and somewhat broader than any of the preceding tarsal joints; fifth joint considerably dilated, flattened, oval, dark brown, fringed with short black hairs on its outer edge. The claws are inserted on the middle of the inner long side of the oval; hence the dilatation cif the fifth joint has not taken place, as in some other species, at right angles to the long axis of the tarsus, but obliquely. Median femur with preapical bristle; median tarsi dark brown or black from the tip of the first joint. Hind femora with short preapical bristle, ciliated on both their anterior and posterior edges. The pos- terior cilia are black, very long and form a series extending nearly the entire length of the posterior face ; near the base of the femur, however, they become much shorter and pale yellow; the cilia of the anterior edge are all black, much shorter and occur only on the basal half of the femur. Hind tibiae some- what incrassated with infuscated tips; the usual setae are long and conspicuous ; on the inner face a dark brown band runs from the insertion of the tibia to its middle, where it ends in a point; the infuscated tip of the tibia sends out a much shorter dark brown band which stops before reaching the basal band. Hind tarsi deep black, the nietatai-sal joint a little thickened. Halteres honey yellow. Wings uniformly grayish hyaline with brown veins ; costa slightly thickened where it meets the first longitudinal vein ; fourth longitiidi- nal vein not broken, but exhibiting the usual double flexure ; posterior cross vein meeting the fifth longitudinal vein nearly at right angles.
HABITAT : Massachusetts.
This species
may be easily distin-
guished from all described North Amer-
ican species of Dolichopus by the pecu-
liar coloring and conformation of the
fore feet. The descripiton is taken from three males sent me by Mr. S. Henshaw.
DOLICHOPUS GERMAKUS, n. sp. 8. 9.
$ Length 4.~5 mm. ; length of wing 4.-
4.5 mm.
Metallic green, not very bright. Palpi pale yellow, face rather narrow, silvery white. Antennae of the same shape as in D. varia- bilis, smooth, red; first joint rather long, cuneate; second joint short and broad : third joint of moderate size, about as broad as long; apical half infuscated, ending in a short but acute point; arista inserted on about the middle of its dorsal contour. Front sub- dued metallic green ; cilia of the superior orbit black, on the inferior orbit dirty white. Thoracic dossum metallic green
with a golden reflection, dusted in front with yellowish scales ; pleurae metallic green, becoming pearly from a covering of white



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342 PSYCHE. [May 1890.
dust. Cilia of the tegulae black. Scutellum concolorous with the thoracic dorsurn. Ab- domen metallic green, passing into cupreous on the apical half; venter dusted with white, its short hairs pale yellow; hypopygium
large, black, with metallic green reflection on its basal half, thinly covered with white dust; penis and internal appendages pale yellow; lamellae white, of moderate size and irregularly trigonal shape ; apical mar- gins rather broadly bordered with black and broken into a jagged fringe of bristles, which seem to be white with black bases. From
the posterior edge of each lamella projects a broad, flat, bifurcate bristle. Coxae and legs pale yellow; the latter dusted with silvery white dust. Fore coxae covered with short white hairs anteriorly and bearing several conspicuous black bristles near their tips ; the median coxae have, besides a few long and curved black hairs on their anterior faces, a long and straight black seta on the lateral face near the tip and a brown spot at the base ; hind coxa near its tip with a black bristle which is only about + as long as the corres- ponding one on the median coxa. Fure tar- sus plain, about r+ times as long as the fore tibia, the last joint but very slightly, if at all, dilated, black, contrasting with the pale yel- low of the other tarsal joints. Posterior fem- ora each with a prominent preapical bristle; the hind pair eciliate; the black bristles of the posterior tibiae well developed and con- spicuous ; median tibiae with four equal setae at their tips; posterior tarsi blackened from the tip of the first joint; usually on the me- dian pair the second joint and the tip of the first are more dark brown. Hillteres pale yellow. Wings hyaline, with a brownish
tinge; narrow at their bases and somewhat pointed at their apices; veins yellow; one or both of the angles of the double flexure in the fourth longitudinal vein somewhat more acute than in many species of Dolichopus. The posterior cross-vein, though perpendicu- lar to the fourth longitudinal vein, forms an angle less than go" with the fifth longitudinal vein.
9. Length 4.5 mm. ; length of wing 4.5