J. Bequaert.
Further Studies of the Tabanidae of Trinidad, B.W.I.
Psyche 51:12-21, 1944.

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Psyche
[March- June
FURTHER STUDIES OF THE TABANIDE
OF TRINIDAD, B. W. I.
Harvard Medical School and School of Public Health, Boston, Mass.
The publication of my list of Trinidad Tabanidse a few years ago (1940, Bull. Ent. Res., 30, pp. 447-453) induced several entomologists to a more intensive study of these flies. Dr. E. McC. Callan submitted for identification two lots, including all specimens in the Department of Entomology of the Imperial College of Tropical Agriculture. More recently Dr. Raymond C. Shannon, of the International Health Division, The Rockefeller Foundation, forwarded to me many specimens obtained by him and his associates in the course of their studies on malaria. The result is most gratifying and has induced me to draw up a revised list of the species known from the island. This was the more necessary because recent careful work on the Panamanian fauna by Dr. G. B. Fairchild has resulted in certain corrected identifications and names. Some of these changes were decided upon in personal discussion with Dr. Fairchild, and most of them have since been published by him. None of the inforrna- tion given in my earlier paper is repeated here, unless it called for correction.
The number of known Trinidad Tabanidse has risen now from 23 to 3 1 species, 9 species being added. One of the species of the earlier list (Tabanus ochrophilus) was dropped, as the specimen on which the record was based is not now available for study and was no doubt misidentified. The following changes in nomenclature were made. The species formerly listed as Chrysops auroguttata is now called Chrysops pullidefemorata Krober. Stibasoma dyridophorum becomes a synonym of S. mallophoroides. The older name T. limonus is applied to the species formerly called T. viridis. In accordance with G. B. Fairchild's recent work, T. amplijrons is used for the species I called T. trilineatus and T. vittiger subsp. guutemalanus for Pu&e 51:12-21 (1944). hup Wpsycht einclub org/S1/51-012 html



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19441 Further Studies of the Tabankh 13
the females formerly called T. carneus; while T. appendiculatus is considered a synonym of T. lineola var. carneus. Two species of Tabanidx are now known from Tobago: Tabanus amplijrons and T. leucaspis, both common in Trinidad. In my earlier paper a brief comparison was drawn between the tabanid faunae of Trinidad, the Antilles, and continental South America. This was somewhat amplified in my monograph of the Tabanidae of the Antilles (1940, Rev. de Entomologia, 11, p. 2 71-2 72). The conclusions reached at the time are merely confirmed by recent additions. The purely South American character of the Trinidad tabanid fauna remains beyond dis- pute. All nine genera of the revised list are found on the con- tinent. This is true also of the nine subgenera here included in the genus Tabanus, some of these groups being given generic rank by recent authors (Stenotabanus, Leucotabanus, Chloro- tabanus, etc.). The 3 1 species likewise all occur on the Amer- ican mainland, where most of them are widely distributed. On the other hand only four of the nine Trinidad genera are repre- sented in the Antilles (Chrysops, Lepiselaga, Dichelacera, Tabanus) ; while of the nine subgenera of Tabanus, five occur in Trinidad as well as in the Antilles (Chelotabanus, Bellardia, Chlorotabanus, Macrocormus and Stenotabanus). Of the 3 1 Trinidad species, only five are definitely known from the An- tilles : Chrysops variegata, Lepiselaga crassipes, Tabanus hooker;, T. vittiger ( = T. truquii of my Antillean monograph) and T. lineola. (T. ferrifer has been recorded doubtfully from Barbados). These five species are widely distributed through- out tropical America, T. lineola occurring even in the Nearctic Region.
1. Chrysops variegata (Degeer ) .
2. Chrysops tristis (Fabricius).
3. Chrysops fulviceps Walker ( = C. auro f asciatus Krober ) . 4. Chrysops pallidefemorata Krober ( = C. auroguttatus var. pallide f emoratus Krober, 1930, Zoolog. Anzeiger, 90, p. 72, figs. 9-10; 9 ; Trinidad).
Lezard Swamp, female (R. C. Shannon) ; Caroni Swamp, fe- male (R. C. Shannon).
These two specimens agree with Krober's figures of the head, antenna (partly drawn) and wing pattern of var. pallidefemo- ratus, not with those of his typical auroguttatus (Zbid., p. 71,



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14 Psyche [March- June
figs. 6 and 8). The second tergite of the abdomen bears a small median apical pale spot.
A renewed study of these specimens and of some other ma- terial in our collections has led me to separate pallidefemorata as a distinct species. The from is considerably broader than in uwoguttata; the second antenna1 segment is relatively shorter and the first somewhat swollen; the hyaline area in the fourth and fifth posterior cells touches the discal cell; there is no trace of a hyaline spot near the base in the first submarginal cell; and the apical dark streak of the wing is more deeply notched at the base by the hyaline area, so that its apical portion appears wid- ened. The three females from Quintam Roo, Mexico, which I called C. incisa in my paper on the Yucatan Tabanidae (1932, JI. New York Ent. Soc., 39, for 193 1, p. 535) were really C. pdlidefemorata, so that the species appears to be widely distributed.
The specimens which I listed from Trinidad under C. awo- guttata in my earlier paper (1940, p. 448) are not now available, so that I am unable to place them under either that species or C. pallidefemoruta. There is even a possibility that the Trin- idad cotype of awoguttata. was really a pdlidefemorata and that Krober's drawings of auroguttata were made from the Colombia cotype (both cotypes are at the British Museum). For this rea- son I omit provisionally the true awoguttata from the Trinidad list. The female from Costa Rica (Carillo), which I reported in 1940, was Krtiber's true auroguttata and this is also true of the Panama records published by Pechuman (1937, Rev. de En- tomologia, 7, p. 136) as C. awoguttata var. pallidefemorata, and by G. B. Fairchild (1942, Proc. Ent. Soc. Washington, 44, p. 4) as C. incisa,
Whether Chrysops incisus Macquart (1845, Mkm. Soc. R. Sci. Agric. Arts Lille, for 1844, p. 172, PI. IV, figs. 12-1 2a; 9 ; "New Grenada") was C. woguttata Krober, C. paliidefemorata Kr~ber or some other species ( ? melama Hine) appears impos- sible to decide, unless Macquart's type could be found. The description is vague (the yellow stripes on the sides of the mesonoturn are not mentioned) and the drawings are too crude to be reliable.
5. Chrysops bulbicomis Ad. Lutz.
St. Augustine, 2 females (W. Cook; one of the specimens had



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19441 Further Studies of the Tabmidoe. 15 been named C. Zceta, a species not known from Trinidad); St. Augustine, male, allotype (A. M. Adamson); Penal, female (R. C. Shannon) ; also 3 females from Trinidad, without more definite locality (Stanton Crawford). The species also occurs in Bolivia (Monte S. Pablo).
The markings of body and wings are somewhat as in C. hta (Fabricius) ; but C. bulbicornis is readily recognized by the conspicuously swollen first antenna1 segment and the prominent, conical callosities of the face. In addition, the female has rows of lateral spots on tergites 3 to 6, which tend to fuse into lateral stripes, and the apical black streak of the wing fills the mar- ginal cell completely (the hyaline area not crossing the second longitudinal vein).
Male (undescribed) . Antennae as in female, the first segment conspicuously swollen, pear-shaped, both in profile and from above ; facial callosities very prominent, cone-shaped ; eyes broadly contiguous. Head, including palpi and first two anten- nal segments, honey-yellow (third segment lacking). Thorax
black, covered with black and gray hairs; scutellum and pleura slightly brownish; mesonotum on each side with a prominent yellow stripe. Legs mostly honey-yellow, with black pile; cox% more brownish. Abdomen brownish-black; dorsum narrowly golden-yellow along extreme sides, with a median row of small, triangular yellow spots on tergites 2 to 5 (more rounded off on tergite 2) and small marginal lateral spots on tergites 3 to 5 (free from the median spot on tergites 3 and 4; narrowly con- nected on tergite 5). Wing much as in the male of C. Ixta (see Krober, 1925, Konowia, 4, PI. Ill), but apical black streak filling entire marginal cell and anal cell without distinct hyaline streak (though with a slightly paler area). Length, 7 mm.; of wing, 6.5 mm.
6. Esenbeckia prasiniventris ( Macquar t ) . St. Augustine, female, the prey of a bembicid wasp, Rubrica surinamensis (Degeer) (E. McC. Callan); Maraval, female (Imper. Coll. Trop. Agric. ) .
7. Lepiselaga crassipes ( Fabricius ) .
Pt. Fortia, female (R. C. Shannon).
Widely distributed in the Greater Antilles, Central and South America.




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16 Psyche
[March- June
8. Selasoma tibiale ( Wiedemann) .
9. Stibasoma fulvohirtum (Wiedemann) .
Balandra Bay, female (W. Cook) ; Brasso, female, biting man (E. McC. Callan); Cumato, female (R. C. Shannon); Point Gourde, female, biting man (E. McC. Callan); Rio Claro, female (R. C. Shannon).
10. Stibasoma mallophoroides (Walker) ( = Stibasoma dyrido- phorum Knab) .
Balandra, female (E. McC. Callan).
Hine, who examined the type of Walker's species at the Brit- ish Museum, wrote in his manuscript notes: "Type ? very much like S. dyridophorum Knab; wings almost exactly the same; the discal spot is hyaline in mallophoroides and extends into second basal cell, as is the case in Knab's species. It would seem that the variation known to exist in this genus would bring the two together." This synonymy was accepted by me in 1940 (Rev. de Entomologia, 11, p. 272). S. mallophoroides was described from the Amazon region, Brazil. 1 1. Dichelacera ochracea Hine.
Valencia, 2 females, biting man (E. McC. Callan). 1 2. Tabanus (Chelotabanus) discifer Walker , 1 8 5 0 ( = Ta banus albomaculatus Walker, 1854).
Arima, female (E. McC. Callan) ; Rio Claro, female (E. McC. Callan) ; Tamano, female (R. C. Shannon). The species is known also from Brazil (Para; San Alberto on the Rio Branco in the State of Amazonas), Dutch Guiana and Venezuela. T. discifer was based on the female, T. albomacu- latus on the male. Krober (1931, Zool. Anzeig., 96, p. 53) re- ported it from Trinidad and recognized that discifer and albo- maculatus were the two sexes of one species. I was inclined at one time to regard Tabanus guttigaster Krober (1934) (= T. guttiventris Krober, 1929) as the same species and used that name in my paper on Antillean Tabanidae (1940, Rev. de Entomologia, 11, p. 272) ; but this synonymy is uncertain and T. discifer is, in any case, the older valid name. 1 3. Tabanus (Chelotabanus) ferrifer Walker . St. Augustine, many females and males (J. T. Gonzalves; A. C. Salazar; E. McC. Callan; A. M. Adamson; Ruth O'Con- nor ; M. D. French-Mullen ; D. K. Kevan) ; also one female



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19441 Further Studies of the Tabanidce 17 as prey of the bembecid wasp, Rubrics su~inamensis (Degeer). El Dorado Village, female (M. V. Beattie; named T. ferrijer by the late Major E. E. Austen) ; Nariva Swamp, female (R. C. Shannon) ; Mundo Nuevo, female (R. C. Shannon) ; Tamano, female (R. C. Shannon) ; Siparia, female (R. C. Shannon). According to Dr. McC. Callan, this is one of the commonest horseflies at St. Augustine, the males being found in ones and twos sitting in sunny places from about 8 A.M. to 4 P.M. 14. Tabanus (Bellardia) xipe Krober.
St. Augustine, male, October 22, 1937 (A. M. Adamson); Tamano, female (R. C. Shannon).
Male (undescribed). - Differs from the male of T. ferrijer in size, extent of the velvety-black spot of the scutellum, mark- ings of abdomen, color of wings, presence of a long appendix at the fork of the third longitudinal vein, and shape of antennae In all these characters it agrees with the female of xipe. The eyes are entirely bare and divided into an upper zone of en- larged and a lower zone of small facets. Dr. Shannon sketched the eye of the female as purple with three green cross-bands, the upper one rather broad but short, the lower one very broad and somewhat narrowed outwardly, the middle one much narrower than the others and somewhat wavy.
According to G. B. Fairchild (1942, Psyche, 49, p. 8) Lopho- tabanus Szilhdy ( 192 6) is not subgenerically separable from BeZZardia Rondani (1863), an opinion with which I concur. 1 5. Tabanus (Phaeotabanus) serniflavus Krober. Princes Town, female (R. C. Shannon).
This specimen agrees with two females I have seen from Brazil (Curralinho, State of Para).
The species was first de-
scribed from Venezuela.
1 6. Tabanus (Chlorotabanus) mexicanus Linnaeus. Tamano, female (R. C. Shannon).
1 7. Tabanus (Cryptotylus) unicolor Wiedemann. Mayaro, female (D. K. Kevan) ; Tamano, 2 females (R. C. Shannon).
18. Tabanus (Cryptotylus) limonus Townsend ( = OmmaZZia viridis Enderlein) .
G. B. Fairchild (1940, Rev. de Entomologia, 11, pp. 720-



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18 Psyche [March- June
722) established what appears to be the correct synonymy of this species. It is known at present from Mexico, Guatemala, Honduras, Panama, Colombia, Trinidad and northern Brazil. At one time I referred the Trinidad specimens to Tabanus luteoflavus Bellardi (see J. Beqaert, 1940, Rev. de Entomolo- gia, 11, p. 272) ; but this was erroneous. As for the green male from Paraguay which I mentioned at the close of the discussion of T. viridis, it has now been recognized as that of Tabanus (Cryptotylus) p~inceps Brkthes.
1 9. Tabanus (Leucotabanus) leucaspis Wiedemann. Princes Town, female (R. C. Shannon) ; Saut d7Eau Bay, female, biting man (E. McC. Callan) ; St. Augustine, 2 females (Ruth O'Connor) ; Tacarigua, several females (T. H. Khan) ; Tamano, female (A. M. Adamson) ; Maracas Valley, female (M. V. Beattie). Other females merely labeled Trinidad (Stan- ton Crawford).
A common species in Trinidad. I have also seen one female from Speyside, Tobago (biting man) (E. McC. Callan). 20. Tabanus (Macrocormus) sorbillans Wiedemann. St. Augustine, 4 females (A. M. Adamson; E. McC. Callan) and 2 males (Ruth O'Connor) ; Tamano, female (R. C. Shan- non).
According to a sketch by Dr. Shannon, the eye of the female is purple with 2 rather narrow green cross-bands in life. 2 1. Tabanus (Stenotabanus) maculifrons Hine. Blanchisseuse, female (R. C. Shannon).
This remarkable little horsefly was originally described from Guatemala (1907, Ohio Naturalist, 8, p. 2 2 2 ; 9 ) . I have taken a female in Colombia (Caney River near Restrepo, Int. Meta) and G. B. Fairchild found it in Panama. The eye, which I ob- served in life and which was also sketched by Dr. Shannon, is pale purplish with two moderately broad, unconnected bluish- green cross-bands: one shorter, starting from the frontal callus; the other in the lower third, curved upward at the outer end. 2 2. Tabanus (Neotabanus) hookeri Knab.
St. Augustine, several females (D. J. Billes; E. McC. Callan; D. K. Kevan) ; also one female as prey of Rubrica shamensis (Degeer) and one male as prey of Stictia signata (Linnseus) (E. McC. Callan) ; El Dorado Village, female (M. V. Beattie).



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19441 Further Studies of the Tabanidce 19 2 3. Tabanus (Neotabanus) johannesi Fairchild ( 1942, Ann. Ent. Soc. America, 35, p. 164, pi. 1, fig. 6 ; ? 8 ) .
Nariva Swamp, female (R. C. Shannon).
This specimen was compared with a paratype from Brazil The species is known also from Paraguay. 2 4. Tabanus (Neotabanus) amplifrons Krober ( = Tabanus tri- lineatus J. Bequaert, 1940; not of Latreille). St. Augustine, several females and males, one male taken at light (E. McC. Callan; A. M. Adamson; P. C. Atteck). Ta- mano, female (R. C. Shannon); Toco, 2 males (R. C. Shan- non) ; El Dorado Village, 2 males (M. V. Beattie) ; San Fernando, male (C. B. Williams).
It is the species which I called T. trilmeatus in my 1940 paper. As shown by G. B. Fairchild (1942, Ann. Ent. Soc. America, 35, p. 178), Latreille's T. trilineatus appears to be un- recognizable. T. amplijrons is known also from Texas, Guate- mala, Panama, Colombia, Venezuela and the Amazon Basin of Brazil. In Trinidad it is one of the most common horseflies. According to Dr. E. McC. Callan, the males are often observed in numbers, sometimes even in hundreds, flying and hovering over roadways from about 6 A.M. to 9 A.M. 2 5. Tabanus (Neotabanus) vittiger var. guatemalanus Hine ( = Tabanus carneus J. Bequaert, 1940; not of Bellardi). Moruga, female (R. C. Shannon). The females from Trin- idad and Siparia, Trinidad, referred to T. carneus in my 1940 paper were guatemalanus; but the Trinidad male of carneus was that of T. lineola var. carneus.
The var. guaternalanus is widely distributed in Central and northern South America.
In a former paper (1940, Rev. de Entomologia, 11, pp. 2 72 and 352), I identified T. vittiger Thomson (1868) with Tabanus truquii Bellardi (1859) ; but Dr. G. B. Fairchild does not agree with this. He regards Bellardi's species as unrecognizable, al- though possibly the same as Tabanus amplifrons Krober. He also treats the Antillean specimens of T. vittiger as a distinct race, which he calls subsp. caymanicus (1942, Ann. Ent. Soc. America, 35, p. 180) ; but the distinction between guatemalanus and caymanicus seems to be too finely drawn and based mainly on distributional data, not on reliable characters.



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20 Psyche [March- June
26. Tabanus (Neotabanus) angustivitta Krober. Nariva Swamp, female (R. C. Shannon).
G. B. Fairchild saw this species from Mexico, Guatemala, Panama, Colombia, Venezuela, British Guiana, Brazil, Ecuador, Peru, Paraguay and northern Argentina.
2 7. Tabanus (Neotabanus) fumatipennis Krober. G. B. Fairchild, who discusses this species at some length ( 1942, Ann. Ent. Soc. America, 35, p. l62), saw specimens from Trinidad, as well as from Costa Rica, Panama, Brazil and British Guiana.
2 8. Tabanus (Neotabanus) lineola var. carneus Bellardi ( = Ta- bonus appendiculatus Hine) .
Yarra River, male (R. C. Shannon) ; Rio Claro, female, bit- ing mule (E. McC. Callan); St. Augustine, female, prey of Rubrica surimmensis (Degeer) (E. McC. Callan) ; Maracas Bay, female (P. C. Atteck) ; Mayaro, female (D. K. Kevan) . The specimens from Port of Spain and St. Augustine, listed as T. appendiculatus in my 1940 paper, were also T. lineola var. carneus.
The var. carneus is a common horsefly in Trinidad. It occurs over most of the Neotropical Region, from Mexico to Paraguay and southern Brazil.
No other form of T. lineola is known thus far from Trinidad.
Tabanus ochrophilus of my 1940 paper is omitted here. It is extremely doubtful that the specimen I saw from Trinidad (not now available for study) was Ad. Lutz's species, which was perhaps only a variant of T. lineola var. carneus, as sug- gested by G. B. Fairchild (1942, Ann. Ent. Soc. America, 35, p. 175).
The difficult group of trivittate American species, grouped under Neotabanus, has recently been revised by G. B. Fairchild and his conclusions are here accepted. The following key of the seven forms definitely known from Trinidad will replace what I wrote in 1940 (Bull. Ent. Res., 30, pp. 452-453). ..............................
1. Subcallus bare and shiny in both sexes 2. Subcallus pollinose and dull in both sexes ............................ 3.
2. Subcallus honey-yellow. Wing hyaline. Mid-dorsal stripe of a series of tri- angles; lateral stripes broken up into oblique spots. Female: frons about three times as high as wide, slightly narrowed below. Male: upper two- thirds of eye hairy and with the facets much larger than those of lower ...............................
third. Length, 9 to 12 mm.
T. hookeri.
Subcallus dark drown to black.
Wing slightly smoky. Mid-dorsal stripe of narrow truncate triangles; lateral stripes of a series of short streaks in line.



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19441 Further Studies of the Tabanidce 21. Female: frons at least five times as high as greatest width, slightly narrowed ........
below. Length, 9 to 12 mm. (Male unknown) T. fumatipennis. 3. Female: frons less than three times as high as wide and nearly parallel-sided; frontal callus at least as wide as high and nearly as wide as frons. Lateral ...........................
stripes decidedly step-like. Wing, hyaline 4. Female: frons at least three times as high as wide (usually much higher) ; in doubtful cases narrowed below; frontal callus as high as wide or higher and narrower than frons. Lateral stripes usually regular. Fore cox= and most
femora largely pale or yellowish .................................. 5. 4. Fore cox= and most femora largely black. Scutellum black, Mid-dorsal stripe a slender even line. Female: frontal callus dark brown to black. Male: upper half of eye hairy, but with the facets only slightly larger than those of lower half (the line of demarkation between the two types not clearly defined). Length, 11 mm. ............................. T. johannesi. Female: fore cox= and most femora pale; scutellum reddish; mid-dorsal stripe a series of contiguous triangles; frontal callus yellowish-brown. Length, 11 to 14 mm. (Male unknown) ............... T. angustivitta. 5. Grayish; abdominal stripes broad and quite even, covered with chalky-white hair. Wing hyaline. Female : f rons nearly parallel-sided ; frontal callus grownish, only slightly higher than wide. Male: upper half of eye hairy, but with the facets only slightly larger than those of lower half (the two areas not clearly defined). Length, 12 to IS mm. ........ T. amplifrons. Grayish to yellowish-brown; abdominal stripes covered with grayish-white or yellowish hair. Female: frons narrowed below; frontal callus usually decidedly higher than wide ...................................... 6. 6. Wing hyaline. Female: frons somewhat less than four times as high as great- est width; frontal callus large, yellowish-brown. Male: upper two-thirds of eye hairy and with the facets much larger than those of lower third. Length, 12 to 14 mm. ................... T. vittiger var. guatemalanus. Wing somewhat clouded, at least along the veins. Female: frons at least four times as high as greatest width; frontal callus rather small, dark brown to black. Male: upper two-thirds of eye bare, but with the facets much larger than those of lower third. Length, 12 to 14 mm. ................ ...................................... T.lineola var.carneus. 2 9. Diachlorus scutellatus Macquart.
Trinidad, without more definite locality, female (W. Urich) . This insect was sent to the U. S. Nat. Mus. and determined by Dr. Alan Stone, who sent it to me for study. The species is known also from French Guiana, British Guiana and Brazil. 30. Diachlorus curvipes ( Fabricius ) .
Nariva Swamp, female (R. C. Shannon). The species is known with certainty from Panama, Colombia (Muzo, Dept. Boyaca), British Guiana, French Guiana, Venezuela, and Brazil. Surcouf's citation of "Uruguay" was an error for Para- guay; but the occurrence in paraguay is doubtful. 3 1. Acanthocera marginalis Walker.
Diego Martin, female (D. J. Billes) ; Morne Bleu, 2,700 ft. female, biting man (E. McC. Callan) ; Talparo, female, biting man (E. McC. Callan).




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