J. Bequaert.
Notes on American Nemestrinidae.
Psyche 37:286-298, 1930.

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Psyche
[September
NOTES ON AMERICAN NEMESTRINIDAE
BY J. BEQUAERT
Department of Tropical Medicine,
Harvard University Medical School
Most of the following notes have been in manuscript for a number of years, pending their inclusion in a revision of the American representatives of this family. The recent
discovery of some of these flies in Yucatan prompts their publication in the present form.
Subfamily Nemestrininae
The subfamily Nemestrininae should, in my opinion, comprise all nemestrinids with an elongate, slender, hard proboscis, the labium usually provided with narrow labella. All the North and Central American species belong to one genus, Neorhynchocephalus.
Neorhynchocephalus Lichtwardt
Neorhynchocephalus Lichtwardt, 1909 (July), Deutsch. Ent. Zeitschr., p. 512 (based upon two species: Rhyn- chocephalus sackeni Williston, 1880, and R. volaticus Williston, 1883) ; 1910, Loc. cit., p. 592. Rhynchocephalus subgenus Nemestrinopsis Cockerell, 1910 (October), Bull. Amer. Mus. Nat. Hist., XXVIII, p. 285 (type by original designation : Rhynchocephalus volaticw Williston, 1883).
This genus, which is exclusively American, may be de- fined as follows:
Medium-sized flies, densely pilose, often with narrow hair-bands on the abdomen; the integument black, dark brown, or reddish yellow. Head broad and short, flattened



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19301 Notes on American Nemestrinidae 287 hemispherical. Face flattened or slightly concave. Frons flattened; linear or more or less narrowed beneath the oceilar triangle in the male (the eyes almost holoptic in certain species) ; very broad in the female, often occupying about one-third of the width of the head. Eyes bare. Pro-
boscis elongate, stylet-like, slender, usually directed down- ward and backward, more rarely slanting forward; termi- nal labella long and slender, slightly flattened. Palpi short, very slender. Antennae short; the two basal segments sub- equal, transverse; the third subcircular, flattened with a terminal, three-segmented, bare arista. Ovipositor of female long, sabre-shaped, composed of two slender, curved valves. Wing: alula broad; apical half never with a net- work of cross-veinlets ; branches of third and fourth longi- tudinal veins long, running parallel with the hind margin; third and fourth veins never coalescing before the margin; first and second submarginal cells separated by a cross- vein (Cockerell's outer radio-medial) ; costa as a rule en- closing the hind margin of the wing completely and usually reached by the fifth longitudinal (or apical portion of diagonal vein), which thus divides the third and fifth pos- terior cells; base of fourth posterior cell removed from the anal cell and situated at or slightly beyond the lower basal corner of the discal cell; anterior cross-vein absent, the fourth longitudinal vein usually reaching the third some distance basad of the latter's branching. Genotype, by present designation : Rhynchocephalus volaticus Williston, 1883.
Lichtwardt (1907, Zeitschr. Syst. Hym. Dipt., VII, p. 451) first pointed out that, in the genotype of Rhynchocep- halus Fischer (R. tauscheri Fischer), the upper branch of the fifth longitudinal vein does not reach the hind margin of the wing. He later (1909) proposed a new genus, Neor- hynchocephalus, for the Nearctic R. sackeni and R. volati- cus, in which the hind margin is thickened into a vein, reached by the diagonal vein. Neorhynchocephalus was more fully characterized by Lichtwardt in 1910.l About the same time and quite independently from Lichtwardt, Cock- ere11 also noticed that the diagonal vein extends to the hind margin in R. volaticzis, while such is not the case in typical Rhynchocephalus. He therefore placed R. volaticus in a



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288 Psyche [September
new subgenus Nemestrinopsis. It would seem, however, that he wished to retain R. sackeni Williston and R. sub- nitens Cockerell in Rhynchocephalus, proper, although this is not clear from his paper.
The distinction between Rhynchocephalus and Neorhyn- chocephalus is entirely based upon two peculiarities of the venation. The first of these, viz., the development of the costa along the hind margin and its connection with the diagonal vein, is probably too slight and variable to be of generic value. At any rate, in some of the specimens of N. sackeni which I have examined, certain stretches of the hind margin are not visibly thickened into a vein, and the margin is not fully reached by the diagonal vein, the third and fifth posterior cells being incompletely divided. The second feature, viz., the contraction of the base of the fourth posterior cell, appears to be more reliable: it is present in 40 specimens of Neorhynchocephalus, belonging to the four known species. As a rule, the cell is briefly stalked at the base; but sometimes it is narrowly sessile on the second basal cell. I have seen only one specimen in which it was narrowly sessile on the anal cell, but even this condition is very different from that of Rhynchocephalus tauscheri Fischer, in which the base of the fourth posterior cell touches the anal cell over a long stretch, its lower margin running nearly parallel with the lower margin of the discal cell.
Contrary to Lichtwardt's statement, the shape of the frons in the male is not of generic significance. He writes
that in Neorhynchocephalus the eyes touch each other on the vertex in the male; while the male of Rhynchocephalus has the eyes distinctly separated by the ocelli. In fact, the males of both genera have the eyes separated on the vertex itself by the ocellar triangle ; below this the frons may be more or less narrowed. In N. volaticus and N. sackeni the frons is very much narrowed and linear, so that the eyes seem to touch each other. In two males of N. vitripennis (Wiedemann) the frons is moderately narrowed, the eyes being distinctly separated.
The Zoological Record lists Neorhynchocephalus as dating from this 1910 paper; but the genus was validly established a year before.



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19301 Notes on American Nemestrinidae 289 Quite possibly Neorhynchocephalus should not be given generic rank, and rather be regarded as at most of subgene- ric value. While it is not represented in the Old World, so far as we know, it does not contain all the New World species. Lichtwardt has described Rhynchocephalus mendo- zanus (1910, Deutsch. Ent. Zeitschr., p. 594; s $), from Argentina, which he says has the venation of R. tauscheri, except "dass sich Cubitus und Media in einem Schnittpunkte trennen."
The four known species of Neorhynchocephalus may be separated as follows :
1. Two branches of fourth longitudinal vein united before the costa, the second posterior cell closed and with a long apical stalk. Black, with dense, rather short, pale yellowish pile; the abdomen not distinctly banded nor . spotted. Length, 6 to 10 mm.. .. .N. sackeni (Williston) Two branches of fourth longitudinal vein ending freely in the costa, some distance from each other, the second posterior cell not stalked at the apex .......................... .2. 2. North and Central American species.
Tibiae and tarsi
darker than the femora, especially those of the hind legs. Body covered with pale yellowish pile; the abdo- minal tergites with more or less distinct, white, apical fringes, and with small tufts of black hair on the sides; tergites often spotted with yellowish red. Frons linear in the male, the eyes nearly touching over some length ........
below the ocellar triangle. Length, 8.5 to 14 mm. ................................................ N. volaticus (Williston). South American species. Legs uniformly pale colored, dirty yellow to reddish-yellow. Abdominal tergites without distinct, white, apical fringes, but on the sides with more prominent tufts of hair, which are partly .................................................................................. black. .3.
3. Head, thorax and legs densely covered with long bright sulphur-yellow pile. Wings distinctly infuscated at the extreme base. Length, 8 to 10 mm. (Male unknown ...............................
to me)
.N. sulphureus ( Wiedemann) .




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290 Psyche [September
Head, thorax and legs covered with pale yellowish pile. Wings subhyaline throughout, at most slightly yellow- ish at the base. Male: frons narrowed beneath the ocelli, but the eyes separated by about half the basal width of the ocellar triangle.
Length, 8 to 11 mm. ......
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N. vitripennis (Wiedemann) .
Neorhynchocephalus volaticus (Williston) Rhynchocephalus volaticzis Williston, 1883, Canad. Entom., XV, pp. 70 and 71, fig. 4 ( 9 ; Florida) ; 1886, Trans. Amer. Ent. Soc., XIII, p. 293 ( 9 ) ; 1888, "Synopsis North American Diptera," p. 33, fig. C. W. Johnson, 1895, Proc. Ac. Nat. Sci. Phila., XLVII, p. 325. Wil- liston, 1901, "Biologia Centr.-Amer.," Dipt., I, p. 269. Aldrich, 1905, "Cat. North Amer. Dipt.," p. 219. Cock- erell, 1908, Trans. Amer. Ent. Soc., XXXIV, p. 250. Williston, 1908, "Manual of North American Diptera,?' 3d Ed., p. 186, fig. 68. Kertesz, 1909, "Cat. Dipt.," IV, p. 30.
Neorhynchocephalus volaticus Lichtwardt, 1909, Deutsch. Ent. Zeitschr., p. 512; 1910, Loc. cit., p. 593, fig. 2. C. W. Johnson, 1913, Bull. Amer. Mus. Nat. Hist., XXXII, p. 54. F. M. Hull, 1923, Ent. News, XXXIV, p. 275 ( 9 8).
Rhynchocephalus (Nemestrinopsis) volaticzis, Cockerell, 1910, Bull. Amer. Mus. Nat. Hist., XXVIII, pp. 285 and 286.
Rhynchocephalus species, Osten Sacken, 1886, "Biologia Centr.-Amer.," Dipt., I, p. 73 ( $ ) .
SPECIMENS ExAMINED.-F~o~~~~ : one female (holotype) and two other females, without more definite locality (Riley Col1.-U. S. Nat. Mus.) ; St. Augustine, one male (C. W.
Johnson Coll.) ;
Georgiana, one female (Whitfeld Col1.-
U. S. Nat. Mus.). Texas: one female and one male, with- out more definite locality; Cotula, one female, May 12, 1906 (J. C. Crawford Co1l.-U. S. Nat. Mus.) ; two males, labelled "Neucest" (Marlatt Col1.-U. S. Nat. Mus.) ; Ray-



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19301 Notes on American Nemestrinidae 291 mondville,
one female and one male (F. M. Hull Coll.). Mississippi : Agricultural College near Starkville, several females and males (E. K. Dickey, W. E. Anderson, and F. M. Hull Coll.) . Kansas : Bourbon Co., 800 ft., one female (R. H. Beamer Coll.) ; Simmer Co., 1189 ft., one female (R. H. Beamer Coll.) ; Lawrence, one female (C. H. Curran Coll.) ; Douglas Co., one male (W. J. Brown Coll.). Mexico: Presi- dio River, Villa Union, Sinaloa, one female (A. Kusche Coll. U. S. Nat. Mus.3 ; Venodio [ ? Fenochio, Sinaloa] , one female (A. Kusche Col1.-U. S. Nat. Mus.) ; State of Colima, one female (L. Conradt Col1.-U. S. Nat. Mus.) ; Mexico City, one female (Juan Muller Col1.--U. S. Nat. Mus.) ; Mata- moros, Morelos, one female (W. L. Tower Coll.) ; Altamira Farms, four males (M. E. Hoag Col1.-Ac. N. Sci. Phila.). Yucatan: Chichen Itza, three females, and six males, taken in the dry forest, from June 6 to 10, 1929; the species is evidently common in this locality, although difficult to find and to collect; it is on the wing during the warmest and sunniest hours of the day, when it hovers in the bushes, some 2 to 10 ft. above the ground, poising on a spot for many minutes, while producing a characteristic, high- pitched noise; after a while it may rest on the tip of a dry branch.
There are also reliable, published records of N. volaticus from Kingsville, Texas ; West Point, Mississippi ; Chilpan- cingo, Guerrero ; Mazatlan, Sinaloa ; Vera Cruz, Mexico ; and San Geronimo, Guatemala.
Neorhynchocephalus sackeni (Williston)
Rhynchocephalus sackeni Williston, 1880, Trans. Conn. Ac. Sci., IV, 4, p. 243, fig. ( 9 ; Olympia, Washington State) ; 1883, Canad. Entom., XV, pp. 70 and 71 ( 8 ) ; 1894, Ent. News, V, p. 47. Snow, 1903, Kansas Univ. Sci. Bull., 11, 5, p. 214. Hine, 1904, Canad. Entom., XXXVI, pp. 86 and 90. Aldrich, 1906, "Cat. North Amer. Dipt.," p. 219. Cockerell, 1908, Trans. Amer. Ent. Soc., XXXIV, p. 249, PI. XVI, figs. 1 and 3. Kertesz, 1909, "Cat. Dipt.," IV, p. 30. Cockerell, 1910, Bull. Amer. Mus. Nat. Hist., XXVIII, p. 286. Schaeffer, 1912, Jl.



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292 Psyche [September
New York Ent. Soc., XX, p. 296. Cole and Lovett, 1921, Proc. Calif. Ac. Sci., (4) XI, p. 239.
Neorhynchocephalus sackeni Lichtwardt, 1909, Deutsch. Ent. Zeitschr., p. 512; 1910, Loc. cit., p. 593 ( $ 8 ). Rhynchocephalus clauses F. Brauer, 1883, "Offenes Schrei- ben als Antwort auf H. B. Osten-Sacken's 'Critical Re- View,' " Wien, p. 8. Not of Osten Sacken, 1877. Rhynchocephalus subnitens Cockerell, 1908, Trans. Amer. Ent. Soc., XXXIV, p. 250 ( Q ; Clark Co., Kansas) ; 1910, Bull. Amer. Mus. Nat. Hist., XXVIII, p. 286. Schaeffer, 1912, Jl. New York Ent. Soc., XX, p. 296. Neorhynchocephalus subnitens Lichtwardt, 1910, Deutsch. Ent. Zeitschr., p. 593.
SPECIMENS E~~~~~E~.-southern Illinois, one female (C. Robertson Col1.-U. S. Nat. Mus.) . Kansas : Clark Co., one female (F. H. Snow Coll.). New Mexico: West Canyon Camp, Koehler, one female and one male (W. R. Walton Col1.-U. S. Nat. Mus.). Arizona: Huachuca Mountains one male (C. Schaeffer Coll.). Colorado: one female and seven males, without more definite locality (U. S. Nat. Mus. and Zool. Inst. Halle a. S.) ; Fort Collins, one male (in Coll. Johnson). Utah: Mill Creek, one male (L. P. Rockwood Coll.) ; Salt Lake City, one female (E. C. Titus (3011.- M. C. Z. Cambridge). Idaho: Grangeville, one female (J. M. Aldrich Coll.) ; Whitebird, one male (J. M. Aldrich Coll.). California:
Goose Lake, Medoc Co., one male (Holleman Col1.-U. S. Nat. Mus.). Oregon: Mt. Angel, one female and three males (F. Epper Col1.-U. S. Nat. Mus.) ; Forest Grove, one female (11. C. Lane Coll.) ; Lewisburg, one female (J. C. Chamberlin Coll.) . Washington State : one female and one male, without more definite locality (H. K. Morrison Col1.-U. S. Nat. Mus.) ; Yakima River, two females (M. C. Z. Cambridge) ; Rock Lake, one female (U. S. Nat. Mus.).
British Columbia: Vernon, one male (J.
S. Hine Coll.).
There are reliable, published records of N. sackeni from Morton Co., Kansas ; Colorado Springs, Colorado ; Mary's Peak, Oregon ; Corvallis, Oregon ; and Union Co., Oregon.



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19301 Notes on American Nemestr'inidae 293 Professor Cockerel1 informs me that two females and one male have been taken at Boulder, Colorado. After examining a large number of Neorhynchocephalus, I am unable to regard any of the characters given for sub- nitens as of specific or even varietal value. Cockerel1 de- scribed subnitens as follows: "Smaller than R. sackeni Will.; length of wing just over 8 mm. (over 9% in sackeni) ; pubescence paler, with a sort of greenish gray tint; abdomen less hairy, the bases of segments 2-4 broadly exposed, shining black ; ovipositor shorter, with a stronger, more even curvature; eyes apparently lighter and redder; ultimate branches of cubitus (bounding second posterior cell of Williston) uniting a very short distance before mar- gin of wing (a considerable distance in sackeni) ." The difference in the venation especially is unimportant, consid- ering the variability exhibited by most species of Nemes- trinidae. In the series of N. sackeni which I have studied, hardly two specimens are alike in this respect and often the right wing differs considerably from the left. For instance, the third submarginal cell may be petiolate at the base or broadly or narrowly connected with the first submarginal. In one female, from Salt Lake City, the left wing is fairly normal, but in the right wing the third submarginal cell is subdivided at about its basal quarter by a supplementary cross-vein. A somewhat similar abnormal division of the third submarginal cell in one wing is present in a female from Grangeville, Idaho, in a female from Forest Grove, Oregon, and in a male from Colorado; but the cross- vein is placed at a varying distance from the tip of the cell. A male from Colorado, in V. v. Roder's collection (Zoologi- cal Institute of the University at Halle a. S.), is even more aberrant: while the right wing is normal, in the left wing both the second and third submarginal cells are subdivided by cross-veins, placed a short distance from each other near the middle of the cells; in addition this left wing has a sup- plementary cross-vein about the middle of the fifth posterior cell, uniting the lower border of the fourth posterior cell with the hind margin. Cockerel1 also has figured the closed third submarginal cell of the right wing of a male from Col- orado. The length of the apical stalk connecting the closed second posterior cell with the margin is very variable and



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294 Psyche [September
often different in both wings; in one case the cell being closed at the margin in the left wing and very short-petio- late in the right; at the base this cell may either touch the fifth posterior cell or be removed some distance above it. The fourth posterior cell is either stalked at the base, or sessile, or narrowly connected with the second basal cell. The anal cell is as a rule open on the hind margin; but in one male from the Huachuca Mountains, Arizona, it is dis- tinctly closed. I may also add that in a letter, dated Novem- ber 2, 1929, Professor Cockerel1 has expressed doubts as to the validity of his 8. subnitens. He now thinks it may have been only a variation.
Neorhynchocephalus sulphureus (Wiedemann) Nemestrina sulphurea Wiedemann, 1830, "Aussereurop. Zweifl. Insekt.," 11, p. 631 (no sex given; Minas Geraes, Brazil). Hunter, 1901, Trans. Amer. Ent. Soc., XXVII, p. 149.
Nemestrinus sulphurezcs Kertesz, 1909, "Cat. Dipt.," IV, p. 25.
Neorhynchocephalus szilphureus Lichtwardt, 1910, Deutsch. Ent. Zeitschr., p. 594 ( 9 5 ) .
SPECIMENS EXAMINED.-Two females from northern Ar- gentina: Mist01 Paso near Icano, Chaco de Santiago del Estero (E. R. Wagner-Paris Museum).
Lichtwardt saw Wiedemann's, types in the Vienna Museum and he says that they are male and female. He
also studied three specimens of which he does not give the sex and the locality, in the Berlin Museum, and a female from Asuncion, Paraguay, in the Budapest Museum. The two specimens from Argentina, though otherwise very similar, differ considerably in size; in one the wing is 8 mm. long; in the other 11 mm. The fourth posterior cell is short-stalked at the base in the larger one and very long- stalked in the smalleim one.
Neorhynchocephalus vitripennis ( Wiedemann) Nemestrina vitripennis Wiedemann, 1830, "Aussereurop. Zweifl. Insekt.," 11, p. 631 ( 9 ; Brazil).



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19301 Notes on American Nemestrinidae 295 Prosceca vitripennis Schiner, 1868, "Novara Reise," Zool., 11, Abt. vol. B, Dipt., p. 112. Kertesz, 1909, "Cat. Dipt.," IV, p. 29.
Nemestrina vitreipennis Hunter, 1901, Trans. Amer. Ent. Soc., XXVII, p. 149.
Neorhynchocephalus vitripennis Lichtwardt, 1910, Deutsch. Ent. Zeitschr., p. 594 ( s ) .
SPECIMENS EXAMINED.-Two males. One, merely labelled "Bras.," in V. v. R~der's collection at the Zoological Insti- tute of the University of Halle a. S., is a very old faded specimen, on a short pin, and may have been one of Wiede- mann's cotypes. The other is labelled "Chapada," a locality in the southern part of the State of Matto Grosso, Brazil. This appears to be the first definite locality for the species. Lichtwardt only saw Wiedemann's cotypes at the Berlin a/nd Vienna Museums.
Both males I have seen agree in having a well-developed, though narrowed frons below the ocellar triangles; their venation is practically identical. The specimen from Chapada is the larger, its wing being 10.5 mm. long; that of the other specimen measures 8.5 mm.
Subfamily Hirmoneurinae
The Hirmoneurinae should contain all nemestrinids with a well-developed, but short and broad proboscis, the labium ending in large, fleshy labella.
The alula of the wing is al-
ways broad and the ovipositor of the female is telescope- shaped, consisting of several narrow segments capable of retraction within one another. In North America, this sub- family is represented by two genera, Hirmoneura Meigen and Hyrmophlaeba Rondani.
Hyrmophlaeba brevirostris (Macquart)
Hirmoneura brevirostris Macquart, 1845, Mem. Soc. Sci. Lille, (1844), p. 233, PI. XX, figs. 1-la; 1846, "Dipt. Exot.," Suppl. 1, p. 101, PI. XX, figs. 1 and la ( 8 ;



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296 Psyche [September
Merida). Osten Sacken, 1877, Bull. U. S. Geol. Geogr. Surv. Terr., 111, p. 224; 1878, Smithson. Miscell. Coll., No. 270, p. 85. Williston, 1883, Canad. Entom., XV, p. 70. Aldrich, 1905, "Cat. North Amer. Dipt.," p. 218. Cockerell, 1908, Trans. Amer. Ent. SOC., XXXIV, pp. 251 and 252, PI. XVI, fig. 2; 1910, Bull. Amer. Mus. Nat. Hist., XXVIII, p. 286.
Hermoneura brevirostris Kertksz, 1909, "Cat. Dipt.," IV, p. 25.
Hyrmophlaeba brevirostris Rondani, 1863, Arch. per la Zoologia, Modena, 111, 1, p. 51. Lichtwardt, 1910, Deutsch. Ent. Zeitschr., pp. 580 and 591. J. Bequaert,
1920, Jl. New York Ent. Soc., XXVII, (1919), p. 306. This species, originally described from the State of Yu- catan, has been reported from Mexico by Lichtwardt. I have seen two specimens from Guatemala: El Rancho, one female (J. S. Hine Coll.), and Gualan (in the eastern part), one pale (C. C. Dean Col1.-U. S. Nat. Mus.). Since no adequate description of this insect has ever been given, the following notes may help to recognize it. Female.-Integument of the body uniformly black, en- tirely covered with ashy gray pruinosity. Antennae dark brown, the basal segments paler, the arista black. Probos-
cis and legs pale reddish-yellow, the tibiae dirty white. Body moderately hairy all over.
Ocellar triangle and upper
part of face with black pilosity ; lower part of face and outer orbits with white hairs; two basal segments of antennae with very long and dense, spreading, black hairs, forming fringes above and below. Thorax densely covered with