Ten New Species of Empididæ (Diptera).
Psyche 52(1-2):79-87, 1945.
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Ten New Species of Empididce
TEN NEW SPECIES OF EMPIDIDE (DIPTERA)
BY A. L. MELANDER
In collecting any group of insects some species are rarely en- countered while others are common. In the Empididae species of Empis, Hilara, Rhamphomyia and Platypalpus are numerous and are frequently taken, but it is a fortunate day when the collector can find a Ragas, a Gloma, or an Anomalempis. These last three represent archaic genera, and perhaps in their con- servative characters they are handicapped in competition with those genera where speciation runs rife. In the following pages are presented descriptions of ten new Empididae, selected because of rarity or other noteworthy in- terest. Unless otherwise mentioned the specimens were collected by myself and the types are in my extensive collection of this family.
Anomalempis archon, n.sp.
Female. Length 3.75 mm. Entirely black, the halteres, pul- villi, abdominal hairs and terminal fringe of abdomen alone whitish. Sides of front coarctate, at middle one-fifth the length between antennae and front ocellus, hairs of occiput conspicuous. Dorsum of thorax and abdomen polished, pleurae and coxae gray pruinose, dorsocentrals in more than single row, acrostichals biseriate, notal hairs long and thin. Hairs of middle cox2 longer than trochanters, all femora with setae underneath, each tibia with about six extensor setae. Wings hyaline, stigma narrow, pale brown.
Holotype: Katmai, Alaska, August, 19 17, received from Pro- fessor J. s. Hine.
A larger and more bristly species than A. tacomaz. Melander from Mount Rainier, Washington, but in structure and neura- tion exactly resembling the figure in Genera Insectorum, fax. 185, pi. 5, f. 39 (not f. 38, which is Syndyas polita Loew). In the Washington species the sides of the front are much less Pu&e 52:79-87 (1945). hup Ytpsychu einclub org/S2/52-079 html
80 Psyche [March-June
bowed and the width is one-half the height; the femoral setas are lacking, the hind tibiz have but a single seta, and the coxal hairs are shorter,
Chersodromia megacetes, n, sp.
Length 2 mm. Body black, thinly coated with cinereous pollen except the following polished places: face, proboscis, a narrow vertical stripe on sides of lower occiput, mesonoturn except a narrow margin on sides and rear, most of sternopleura, terminal plate of pygidium and side of front coxse. Palpi yel- lowish. Mesonotal hairs abundant, dark, leaving two approxi- mated glabrous stripes anteriorly, separated by the biseriate hairs of the median line; scutellum thinly cinereous, two apical scutellars. Last tergite of abdomen of male somewhat enlarged on the left side; pygidium enormous, massive, twisted to the right, ventral bowl nearly twice as long as wide, below and laterally on the right side with a few short hairs, left side above with a shining spatulate valve, terminal disk rounded triangu- lar; last segment of female abdomen compressed and shining, as long as other single segments. Legs black, the knees, extrem- ities of tibiae and the tarsi fuscous; femora without bristles other than a small one near knee, hind tibiz with a few small bristles on apical half and inwardly with a terminal lappet, middle tibiae with a flexar comb of short setulse. Wings and veins whitish, the costal bristle black but the minute hairs whitish, crossveins touching, or the posterior crossvein slightly before the anterior; halteres wholly white, Type, allotype and seven paratypes: Corona del Mar, Cali- fornia, 28 December 1944. Seven additional paratypes from the same locality, 2 5 July 1942, from Laguna Beach, 2 5 Janu- ary 1935 and 22 May 1944, and from San Clemente Beach, 23 May 1944. In all, five males and eleven females were taken. The insects occur on the dry sand above the line of washed-in seaweed. They are reluctant to fly, can be driven into the col- lecting net, and are prone to take refuge in the burrows of ~rn~hi~ods.
The species name, while literally meaning a great whale, has been applied to anything excessively large. In the present in- stance the monstrous pygidium, bulking as much as the re- mainder of the abdomen, and relatively larger than possessed by any other fly, warrants even this hyperbolic appellation.
19451 Ten New Species of Empidid& 81
Chersodromia insignita, n. sp.
Length 2 mm. Body black, overlaid with brownish gray pruinosity, the sternopleura mostly polished; hairs and bristles black; base of legs dark; wings maculate. Front about twice as long as width at middle, sides of face diverging below, the face about three times as long as width at antennae; two vertical bristles, one pair each of converging and diverging ocellar bris- tles; antennae black, third joint orbicular, style subdorsal, about three times length of third joint; proboscis black, but little pro- jecting beyond the palpi, which are large, flat, orbicular and glistening white in the male and duskier but glistening in the female. Two dorsocentrals, one humeral, three intra-alar, one post-alar, scutellum with two bristles and two small lateral hairs. Abdomen of male stoutly cylindrical; seventh tergite oblique, lengthened on right side and with hind margin setose, eighth segment filling in the shortened left side of the seventh segment as a shining black triangular plate which is long-setose behind; abdomen nearly bare; pygidium massive, shining above, the globular ventral part pruinose like the preceding abdominal segments, claspers wide and stout. Coxae mostly blackish, legs robust, all femora stout, piceous, knees, tibiae and base of tarsi brownish; front tibiae swollen and bearing a preapical flexar bristle, middle tibiae with two widely separated extensor bristles, of male narrowed on apical third where there is a flexar strigil of about ten short spines, hind tibiae with about ten irregular bristles toward tip; metatarsi cylindrical, the front ones two- fifths the tibia1 length. Wings fully developed, basal half whit- ish hyaline, with a strong sudden infumation in marginal cell beginning opposite crossveins and diminishing but pervading apical half of wing, veins white to, and including, crossveins but apically brownish, costal ratio 12 : 4 : 6 : 3, basal costal bristle black, costal hairs black, hairs of hind margin pale, second vein noticeably diverging from third, sections of fifth vein 5:4; hal- teres black, the short stalk brown; alulse and hairs blackish. Monterey, California; 2 5 September 1934, twelve specimens. This is the only species of Chersodromia having an extended stigmatic spot on the wings.
Coloboneura nubifera Coquillett, from Alaska, likewise pos- sesses a dark wing-cloud. It measures three to four millimeters and differs in having the darkening of the wings restricted to
82 Psyche [March- June
the anterior distal quarter of the wing and in having the second basal cell shorter than the first.
Chersodromia cana, n.sp.
Female. Length 1.4 mm. Body and legs wholly black, more or less overlaid with white-gray pruinosity which is dense on the thorax except the sternopleural spot; all hairs white, all bristles short and black; halteres and palpi white. Front twice as long as width at bottom, face with coarctate sides, five times as long as narrowest width, two pairs of verticals, one of fron- tals; second joint of antennae nearly equal to the rounded third joint, style subapical, about twice as long as the third joint; proboscis retracted. Dorsum of thorax rather evenly covered with appressed white hairs, scutellum with two bristles and two lateral white hairs, one each of humeral, notopleural, propleural and intra-alar. Vestiture of abdomen sparse, last segment com- pressed. Middle tibiae with two extensor bristles, hind tibiae with two extensors near middle and three before tip, front tarsi shorter than tibia, the joints almost globular, the first joint not twice as long as wide. Wings milky white, no stigma, basal costal bristle black, all hairs of wing margin small and white, veins white on basal half and gray on apical half, costal ratio from humeral crossvein 8 : 3 : 5 : 3, crossvein near middle of fifth vein.
Holotype : Laguna Beach, California, 2 5 January 193 5. In the European species, likewise, when the dorsocentral bristles are not developed the notal hairs are pale. Our species differs in having the legs completely black. The distinction between bristles and hairs is clearly indicated by the color. It is worth recording that a specimen of Chersodromia which I collected on the beach near St. George, Bermuda, on February 1, 1934, appears to be identical with Ch. beckeri Melander from the Baltic Sea. Unfortunately the Bermuda as well as the Baltic specimens are known from females only. It may be that the discovery of males will enable a distinction to be made. 1. Mesonotum shining black, no dorsocentrals; pygidium about as large as the rest of the abdomen; legs blackish ; halteres white. Cal. megacetes, n.sp.
Body overlaid with grayish pollen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2. 2. Hairs of mesonoturn white, bristles black, no dorsocentrals; legs blackish; halteres white. Cal. cana, nsp.
19451 Ten New Species of Empididce 83
Hairs and bristles of thorax black, dorsocentrals present though sometimes small. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3. 3. Wing with darkening on apical half; legs fuscous; halteres black; two scutel- lars; second basal cell longer than first. Cal. insignita, n.sp. Wings without cloud, uniformly whitish; legs and halteres yellowish. . . . . . 4. 4. Bristles and hairs of costa and notum black; second basal cell shorter than first. North Atlantic Coast.
Bristles and hairs of costa and notum pale; basal cells equal. Fla. nana Coq.
Ragas primigenia, n. sp.
Male. Length 2 mm. Black, with a thin coating of fine brown- ish pollen. Hairs of lower occiput silky; eyes fully contiguous along the front; ocellar triangle prominent, with five setse; third antenna1 joint triangular, twice as long as deep, style one-fourth the length of the third joint, thick, with a small apical seta; proboscis shining, incurved, sharp, in length one-third the head- height. Notum and pleurse bare of hairs, lateral bristles very small, single hum., ia., and npl., 6 scutellars, dorsocentrals uniseriate, sparse, short, the posterior three longer, acrostichals biseriate, sparse and short. Abdomen nearly bare, pygidium small and open, its valves bifurcate and forcipate. Legs nearly bare, slender, front cox% studded anteriorly with six stubby spines, front trochanters large and furnished with a curved row of about ten spinous bristles, middle femora beneath near mid- dle with two strong bristles. Wings infumated, veins heavy and dark, stigma strong and elliptical, second basal cell a little longer than the first and parallel-sided, discal cell large, acutely pointed at base, the underside one-fourth its length, third vein ending just beyond tip of wing, its sections 2.5 : 1, sections of fourth vein 1 : 5 : 5, of fifth vein 1 : 2, axilla rounding into the prominent anal lobe; halteres blackish.
Holotype: La Jolla, California, 1 January 1935. This is the first valid occurrence of this genus in America, the previous citations of Ragas having been assigned to other gen- era. There is only one other known species, R. unica Walker, from Europe. It is smaller than our form, lacks the armature of the legs, and has thinner veins. Otherwise the two species are closely related. In Curran's book on the genera of North American Diptera Ragas would lead to couplet 33 on page 2 11, differing in having an almost straight complete auxiliary vein and a full anal angle to the wing.
84 Psyche [March- June
Gloma fuscipes, n.sp.
Length 3 mm. Body of male piceous black, legs light fuscous; body of female more or less testaceous below, legs mostly yel- lowish, bristles and hairs shorter than in male. Face deeply recessed; occiput of both sexes blackish, nearly bare behind the orbital fringe; antennae short, the arista arising from the base of the deflected reniform third joint; proboscis short and fleshy, palpi black and hairy. Humeri marked with a fuscous point, 1 hum., 3 npl., 3 ia., acrostichals long and scattered, biseriate. Abdomen of male shining; hairs at incisures nearly as long as the segments, two irregular intermediate rows of shorter hairs. Hind tibiae with about seventeen extensor hairs. Wings some- what smoky, stigma darker, base in female paler than in male, veins thin and piceous, basal cells coextensive, auxiliary vein evanescent toward tip, alulae pale, the fringe dark. Type male: Puget, Washington, 4 July 1925 ; allotype: Pot- latch, on Hoods Canal, Washington, 28 July 19 17. Four male .
and three female paratypes, Canyon Creek, 26 July 1925, and Mount Constitution, 3 1 July 1908, both in Washington; Mount Hood, Oregon, at 3000 ft., 29 July 192 1; Moscow Mountain, Idaho, 10 August 1924, and Lookout Mountain, Priest Lake, Idaho, 20 August 1919.
The genus Gloma is remarkable in the Empididae in having the arista truly dorsal on the small stubby reniform third joint. The South American Hyperperacera Collin, which also has a dorsal arista, has bristly metapleurae.
The species of Gloma are rarely encountered, and occur in the forests of the Pacific North-west. But three species exist in the American fauna, the earlier references to Gloma pertaining to Oreogeton, with Gloma phthia Walker belonging in Syneches. Gloma pectinipes, n.sp.
Length 4 mm. Similar to the preceding species, but larger and with the hairs and bristles abundant and prominent. Lower occipital hairs numerous. Thorax thinly overlaid with cinereous pollen, a fuscous point on the humeri. Abdomen subshining. Fringe of the hind tibiae with about twenty hairs. Wings some- what smoky, stigma darker, veins piceous, alulae dusky; halteres black. The distinctive characters are given in the following table.
194.51 Ten New Species of Empididce 85
Type and allotype: Seward, Alaska, 26 July 192 1, J. M. Aldrich (U.S.N.M.). A paratype, Anchorage, Alaska, 20 July, also from my friend, the late Dr. Aldrich. 1. Posterior terminal prong of basal valve of pygidium slender and as long as the bunch of preapical hairs (in the European fuscipennis Meig. the pos- terior prong is very thin and much longer than the anterior) ; cox= and legs black; radial and cubical veins distinctly stronger than the medial. Wash. luctuosa Mel.
Posterior prong stout and short, about half as long as the hairs of the pre- apical group; radial and cubital veins scarcely stronger than the medial. . . 2. 2. Eight or more scutellar bristles, ten or more dorsocentrals; cox= and legs dark fuscous, both sides of hind femora of male fringed with long hairs, under side of middle femora with about five hairs along the apical half; female black; length 4 mm. Alaska. pectinipes, nsp. Four scutellars, eight or fewer dorsocentrals; cox= and legs light fuscous, of female paler, hairs of under side of femora not longer than diameter of the femur; female body more or less testaceous; length 3 mm. Ida., Wash., Oreg. fuscipes, nsp.
Oreogeton xanthus, n.sp.
Length 7 mm. Male entirely luteous, subshining, female with head and antennae sometimes blackish, with thin dust; bristles and hairs black. Third antenna! joint about as longas deep, shorter than the basal two together, arista apical; proboscis small, fleshy, palpi with numerous bristles. Valves of pygidium deeply emarginate at middle above, the apical corner bluntly digitate, posteriorly with numerous hairs. Middle coxae with blunt setae, those of hind cox= short; male with eight to ten flexar setae on middle femora rather uniformly distributed, the middle tibiae pectinate within with fine setae, and only slightly bent at middle; tarsi simple, last two joints fuscous. Wings with yellowish tinge, stigma slightly darker, veins yellow, the first, second and third setulose above and the second and fourth underneath, sections of fifth vein subequal. Type and allotype: Mount Baker, Washington, Skyline Trail, 10 August 192 5. Six male and five female paratypes: topotypic, and also from Mount Rainier, at White River, 20 July 1924, and Everett, Washington, 4 July 1924.
In the table of species in Fascicle 185 of the Genera Insec- torum, page 99, xanthus leads to capnopterus, but is readily distinct in its yellow color and in having many setae under the middle femora of the male. Xanthus is the only species having
86 Psyche [March- June
the apical finger of the pygidial valves twisted inward. In all the others (male of rufus not in collection) the valve ends in a continuous thin blade-like triangle or hook. Hilara cavernicola, n . sp .
Length 2.25 mm. Testaceo-fuscous, head and genitalia be- coming fuscous; all bristles short. Front of female twice as long as wide, of male two and one-half times, middle frontal seta minute, face as wide as front, gray-dusted, occipital row of brownish hairs inconspicuous, ocellar bristles shorter than style; basal joints of antennae yellowish, third joint brown, triangular, scarcely longer than deep, style slightly longer than third joint; proboscis brown, palpi yellow, with a single small pale seta and a few small hairs. Thorax dusted with concolorous pollen, not vittate, pleurae concolorous with dorsum, dorsocentrals uni- seriate, about ten in number and similar to the acrostichals which are in four rows with about eight to the inside row, four scutellars. Abdomen of male with yellowish incisures, of female wholly fuscous, hairs sparse, short and pale, pygidium about the size of the fifth segment, the valves with hook-like process at anterior apex. Legs without bristles, slender in all parts, coxae and legs pale yellow, becoming slightly darker distally where the ends of the tarsi may be light brown, tibiae almost equal in length to tarsi which are simple and slender, the metatarsi about equal to the two following joints. Wings hyaline, stigma very faint, veins very thin and light brownish, sections of third vein proportioned 1 : 7: 5, of fourth vein 1 :4: 6, of fifth vein equal; halteres pale yellow, alulse and fringe pale. Over one hundred specimens mounted, from Lucerne, Lake Chelan, Washington, 2 9 July 19 19.
Most of the species of Hilara are characterized by their males having enlarged front metatarsi. In Europe there are only some half-dozen species which have slender tarsi, and in the United States but one, H. johnsoni. The discovery of an additional species which has probably reverted to this generalized condi- tion therefore carries unusual interest. Nearly all the species of Hilara frequent open water, over which they weave their aerial dance. The present species was found swarming in an aban- doned mine, evidently attracted there by the enclosed darkness rather than by any dampness.
19451 Ten New Species of Empididce 87.
Empis (Enoplempis) ctenocnema, n.sp.
Length 7 mm. Thorax cinereous piceous, notum quadrivit- tate with brown; four small scutellars. Abdomen with a few lateral setulse in vertical row on first two segments. Legs in- cluding coxse testaceous, tarsi apically piceous, hind femora slightly swollen and bent at apical fifth but without any hairs at swelling, hind tibise with slight swelling on underside toward knee corresponding with femoral bend and with a slight de- pression corresponding with femoral swelling, fringed on both sides with close black hairs; when the knee is flexed the femoral twist lies between the two fringes.
Two males, one female, Tuxedo, New York, 29 May 1926. Very close to E. nodipes Melander, from New Mexico, to which it leads in the table of species of Empis, Trans. Am. Ent. Soc. xxviii, p. 284 (1902). It differs from the description on page 324 only in the structure of the knee specialization of the hind legs.
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