Cornelius B. Philip.
Notes on Nearctic Tabaninæ. Part III. The Tabanus lineola Complex.
Psyche 49:25-40, 1942.

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Nearctic Tabaninas
NOTES ON NEARCTIC TABANINE. PART 111.
THE TABANUS LINEOLA COMPLEX1
By Cornelius B. Philip
Hamilton, Montana.
Among the taxonomic problems needing review, antici- patory to preparation of a catalog of Nearctic species of Tabanidse, is the recurrent question of variation in the com- mon Tabanus lineola Fabr. Relatives of this species with pale abdominal stripes, lately have been referred to Neota- banus Lutz (not Ricardo) (synonym, Tsniotabanus Krober), although the group has not been considered of generic rank by Krober (1934), Stone (1938) or Bequaert (l94Ob). Osten Sacken early pointed out, and Bequaert (1940a) reiterated "the Tabanus with trivittate abdomens . . . are among the most difficult insects to deal with." Hine (1906) attempted analysis of North American spe- cies "with a uniform middorsal stripe . . ." Tinctorially, also included were such species as acutus Bigot and the nigro-vittatus relatives with unibanded, unextended eyes. There is little structurally to define Neotabanus, and nigro- vittatus was also keyed with lineola in this category by Bequaert (1940b). The name might have more taxonomic utility if restricted to the close lineola relatives having the characteristic, multiple eye-banding, and extended outer , angles of the eyes (most noticeable in the females) in ad- dition to the abdominal stripes. Such species as T. pro- ductus Hine and T. texanus Hine form troublesome inter- grades. The former has the characteristic eye-banding, laterally produced head, and a somewhat dorsiger-like ab- dominal pattern which belie the Stenotabanus-like antennas and wing spurs; texanus has a single, narrow purple eye band like nigrwittatus. Some T. sagax 0. S. and rubbed 1The studies on which this paper is based were completed at the Museum of Camparative Zoology, Harvard University, during tenure of a Fellowship from the John Simon Guggenheim Foundation. Psirhe 49:25-40 ( 1942). hup Ifpq~hc enlclub orgt49149-025 html



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26 Psyche [March- June
specimens of a few other species also complicate reliance on the abdominal stripes, so that maintenance of Neotu- banus even as a subgenus appears to be only a matter of arbitrary taxonomic convenience as discussed elsewhere (Philip, 1941). Those undertaking assignment of Neotdf- banus, furthermore, will be faced with clarification of the puzzling description of the head of tdinefttus Latr,, the genotype species.
The Neotropical fauna of this group shows more varia- tion than the Nearctic, as reflected in the numerous specific names proposed by various students particularly in Europe. Only a few of these names are recognizable at present. Bequaert (1940b) has provided useful copies of some of these scattered descriptions, while Krober reports personal study of many of the European types. Until all the per- tinent types can further be studied by a competent student, particularly those of Bellardi, any review such as the pres- ent will have to. rest on tentative opinions, interpretations, and comparison of available materials, using both sexes wherever possible.
The Nearctic T. lineola of authors is a variable complex, and material at hand appears to provide at least 5 forms and possibly more if sexes could be correctly associated. Were it not for evidence of differing males, these forms in part would justify Bequaert's opinion that neither the color of the femora and seutellum, nor the "appendix to the fork of the third vein offer reliable specific characters." An enumeration of these variants will show the necessity for some qualification of this opinion, however. The shapes of palpi and colors of areas of enlarged facets in identical series of males are too variable unfortunately, to be of much supplemental, diagnostic aid.
Independently, Fairchild (unpublished) has come to con- clusions regarding significant, diagnostic characters in the group very close to those of the author. Since a considera- tion of specific trends in both the Nearctic and Neotropical faunae is necessary for a rational treatment of either, it is a. pleasure to acknowledge personal collaboration with Fair- child in arriving at an agreement on the systematic arrange- ment in best accord with present, available information. An unfortunate paucity of information regarding the inter-



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mediate Mexican fauna hinders complete clarification of overlapping.
Until the question of specific and subspecific or varietal status of certain forms and groups can be more definitely established, and the doubt removed regarding the applica- tion of certain names, there is little to be gained in question- ing whether occidentalis L. should replace lineola Fabr. as here recognized or to what form this early name should apply
Tabanus lineola Fabr. s. sir. The original description is inadequate in certain crucial characters, and unfortunately, the probable type is represented at the Kiel Museum by only the thorax, wings, and first 2 abdominal segments. From among a series of forwarded specimens, Dr. 0. Schr~der selected one with a reddish margined scutellum as closest to what remains of the type. The legs were originally described as "pedes nigri tibiis ferrugineis", indicating black femora. If the type really had a red scutellum origi- nally, this would best fit schwardti below, and Maquart's (1838) reference to hairy eyes in the male suggests presence of this form among early material. But since Fabricius described the prescutal lobes as "ferrugineo" without men- tioning the scutellum, the brown now present may be due to a translucency sometimes seen in worn, and pest-destroyed specimens where only the integument remains. In the ab- sence of certainty, it seems best for the present not to change the figured conception of Stone and Bequaert, though the discussions of both were more inclusive than their figures indicate.
What I take to be the males of this form from Michigan and Arkansas (reared by Schwardt) have the areas of en- larged facets in the upper vl, pale buff grey, hairs very short and sparce ("ostensibly bare" for key purposes), the thorax and scutellum subshiny cinereous, the vestiture sparce, all 3 pairs of femora infuscated to the knees, the pale middorsal stripes narrow, the sublateral yellow ones, reduced and broken, the intervals extensive brown, not black, and giving a suggestion of the suffused, less contrasting pattern seen in scutellaris described below. The abdominal stripes of males from the Gulf Coast are more contrasting and regular. The female has a convergent, narrow front, its height



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28 Psyche [March- June
about 6 to 7 times its basal width (in the key the frontal index has been expanded to 1:5 to include the questioned group discussed later). The scutellum, fore and much of the hind femora are blackish or cinereous, the mid-pair are variable. The abdomen is usually reddish laterally, espe- cially in worn specimens, but in a considerable series from Michigan, Ontario and New York, a melanistic variation occurs which resembles the Neotropical plangens Walk. ( ? modestus Wied.) except that the wings of the latter are dis- tinctly fumose especially along the veins, the dorsum of the thorax has a more metallic sheen due to irridescent hairs, and the hairs on the entire fore femora are deep black. Stone informs me specimens of this form in the National Museum are from Mich., Ohio, Me., Conn., N. Y., Pa., Del., D. C., Md., Va., and N. C. I have seen it also from Ont., Mass., Ga., Fla., Tenn., and La.; a single but undoubted specimen bears an early label of Douglas Co., Kans., which may be a mislabel in the absence of any others in a large amount of recent material from that state. It appears to be most abundant along the Atlantic Coast. I also have seen a typical female in Bcequaert's collection from Cuba. Since T. bellardii Szil. from Cuba is described with "front three and a half times as broad as its lower breadth" and "brown antealar swelling and scutellum", Bequaert (1940b) must be mistaken in this synonomy. The description of T. cu- banus Szil. is inadequate for judgment but the "furca with a sharp appendix" and comparison with trilineatus suggest a Neotropical relationship. In all the Nearctic specimens of the various forms I have seen a short spur on one wing of only one specimen. The "carneis" scutellum and pos- terior legs preclude the synonomy of T. carneus Bell. On the other hand, the front of the type of T. commixtus Walk. . from Mexico in the British Museum is said by Oldroyd to agree exactly with Stone's figures of lineoh and, since the femora are blackish, the only difference in the description is the yellow rather than white middorsal stripe. The actual occurrence of the typical form in modern Mexico remains to be verified, however.
T. lineola subsp. scutellaris Wlk.
Possibly the most fa-
miliar to North American students is this form with red- dish scutellum and femora, frontal index ( $ ) 1 : 3 y2 -4u2,



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19421 Nearctic Tabank 29
eyes of the male with very fine, scattered hairs (also "os- tensibly bare"), the slightly enlarged facets confined to the upper half and not flattened on the disc, and the male ab- domen with a brownish suffusion, the stripes somewhat obscured. This is the male described by &ten Sacken (1876) and both sexes by Hine (1903) ; it also is the form reared by the author (1931) in Minnesota and later in Mon- tana, as well as probable by Hart (1896). The sublateral reddish or yellow, abdominal lines are usually irregular, composed of a series of trapezoidal or rhomboidal, connect- ing spots. In a series of pallid California specimens of both sexes, these lines are often obliterated, the lateral yellow being continuous onto the venter. In occasional Northern specimens irregular cinereous spurs or shadows may show basally on the femora while in others even the fore coxse are yellowish. The inner faces of the fore femora are custom- arily shining brown with black pile, but the outer surface is pale pollinose and pilose.
Though the characters of scutellaris would suggest spe- cific distinction from typical lineola and even its close Nearctic variants, intergradation of stenocephalus and cer- tain other Neotropical forms prevent more than subspecific separation at present, as will be discussed by Fairchild in a future communication.
The type of scutellaris is now not present in either the British or Hope Museums with other Saunders types. The described reddish scutellum and "tawny" legs are in agree- ment with this form which Stone (1938) recognized as a variety of lineola. The type data "Bolton, North America" probably refer to a person in part, not a locality according to Oldroyd as some other Saunders specimens carry the label "D. Bolton".
It occurs entirely across the continent in southern Canada and the northern states, the southern records including D. C., W. Va., Ohio, Ill., Iowa, Kan., Colo., Utah, Nev., and Calif. as far south as Los Angeles. I have seen a female each from Utah and Montana with femora somewhat in- fuscated approaching the following.
T. vittiger subsp. schwardti nov.
T.he writer originally intended to retain this provisionally



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30 Psyche [ March-June
under Zineola, but Fairchild has indicated the evident re- lationship of this and nippontucki below with Neotropical variants of which &tiger Thornsen appears to be the prior name, although no males yet are available from the Galapagos Islands.
Thia is the form chiefly reared by Schwardt (1931), and at once distinguished from scutellanS males by the large head with much enlarged upper eye facets occupying fully three quarters of the total eye area, and with more pro- nounced hairs. Furthermore, the palpi are often less blunt and abdominal pattern more contrasting like the females; the fore femora and to a less extent the hind and mid pairs are infuscated. Except for such infuscation of the femora, the females closely resemble those of scwtellaris. For this
reason, the male which is the most distinctive sex is used as type-
Holotype 3, 12.5 mm. Area of enlarered facets chocolate brown (yellow in some paratypes), flattened across disc, hairs distinct, and more dense than in typical Iweolu, ver- tical tubercle small, even with upper eye level, brownish pilose. Face white, palpi creamy with white and occasional black hairs, blunt apically (pointed in many paratypes). Antenna red, annuli black, first segment not unusually swol- len, plate obtuse angulate and very moderately excavated. Thorax quite hirsute, including some pale purplish, appres- sed hairs dorsally and the usual, rather indistinct lines ; pos- terior half of the mutellurn reddish.
Wings hyaline, no
stump. Fore femora, basal two thirds of hind, one fourth of mid-femora, and distal half of fore tibiae and tarsi ciner- ous to blackish. Abdominal stripes distinct and contrast- ing, the median even and white, the sub-lateral irregular and yellow, the 4 intervals dark brown rather than black. Venter yellowish with dusky spots in the middle of the first 2 sternites and edges of all ; black hairs only on last two. Allotype a, 13 mm. In essential agreement with the holotype except for the usual sexual characters. Eyes ex- tended laterally and the characteristic eye pattern (relaxed) usual for the group, front subparallel in upper third, con- vergent below, index 1: 4.8, the basal callosity very deep brown, quadrangular, a little taller than wide, the median callus small and hardly connected. The antenna1 plate nar-



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19421 Nearctic Tabaninas 31
rower and browner distally, the thoracic lines a little more distinct, the dark abdominal lines blacker posteriorly than in the holotype.
Knoxville, Tenn., Sept. 20 ( 8 ) and 25 ( s ) , 1934. In light trap. In the collection of the author through kindness of W. W. Stanley.
Paratypes.-16 8, 16 9, Fayetteville and Washington Co., Ark., (reared), H. H. Schwardt; 9, Drew Co., Ark., Aug. 20, 1928, "W. R. H." ; 9 , Ark. Co., Ark., July 18, 1928, D. Isley; 2 2, Wash. Co., Ark., May 31 and June 10, 1929, D. Isely ;
9 , Hunt, Ariz., Aug. 28, 1919 ; s , New Boston, Tex., May 15, 1906, C. R. Jones;
s , College Station, Texas,
Oct. 19,1919, H. J. Reinhard; 2 9, Brownsville, Texas, June and July, F. H. Snow; 8, 3 9, State College, Miss., Apr. 12, May 7,11, and 17,1939, Smith, Jackson, Macon, and Shivers ; 9, Everglades Exp. Sta., Fla., July 10, 1938, W. C. Stehr; 9, Atlanta, Ga., June 17, 1935, P. W. Fattig; 2 8, Falls Church and Great Falls, Va., June 8 and 30, 1917, C. T.
Greene; 9, Wash., D. C., June 25, 1913, R. C. Shannon; s , Beltsville, Md., Sept. 3,1916, W. L. McAtee; 8, Plummers Is., Md., Mar. 9, 1905, at light, H. S. Barber; 8, 9, Newark
and Dana Landing, Del., July 5, 1938 and June 13, 1935, Donald MacCreary ; s , Melrose Highlands, Mass., July 8, 1908, D. H. Clemons; 2 8, Wooster, and Marietta, Ohio, July 23 and Aug. 4,1938, C. H. Martin; 2 8 ,5 9 , Montgomery Co., Kan. 798', 1916, R. H. Beamer; 4 8, 3 9, Kiowa Co., Kans., July 1-5, 1923, R. H. Beamer and C. L. Woodruff. In the collections of the U. S. Nat'1. Mus., Calif. Acad. of Sciences, Mus. Comp. Zool., Ohio State Museum, Univer- sities of Arkansas, Mich., and Kan., L. L. Peckuman, G. B. Fairchild, H. H. Schwardt, T. H. G. Aitken and the author. In reared or fresh specimens, the vestiture of the scutel- lum sometimes obscures the reddish margin, but seldom completely.
Since Schwardt (1931, 1936 and fig. of egg mass) ob- served 2 generations in Arkansas, it may well be that there are biological differences in different species of the lineola group. Scutellaris and lineola s. sir. are the only other Nearctic forms which have been reared ; the data are too few for comparison, although the adults have a similar long seasonal occurrence in Calif. in contradistinction to the



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32 Psyche [March- June
following form (nippontu,cki) in that area. Pupal dif- ferences have not been discernable.
T. vittiger subsp. nippontucki subsp. ~ov.~ As indicated above, this is a southwestern variant which, in both sexes, resembles schwardti but is much more pallid and frosty appearing, the femora not usually infuscated basally, and the thoracic lines more obscure. Holotype, 8, 12.5 mm. Head large, eyes brown, upper area of enlarged facets extensive occupying % the total area, distinctly hairy, vertical tubercle narrow and reduced. Frontal triangle yellow pollinose extending onto the cheeks along the eye margins. Remainder of face and cheeks whit- ish pollinose and pilose. Palpi pale creamy, whitish pilose, the apical segments plump and with a decurved nipple. Antennae red, scapes not enlarged. Thorax frosty pollinose and pilose, a little darker above with only suggestions of 2 sublateral dorsal lines; prescutal lobes and apical half of scutellum pale reddish. Wings hyaline, venation normal ; halteres pale yellow darker on the stem. Front legs with inner faces of femora, apical half of fore tibiae, and all tarsi dark brown, remainder of legs pale yellowish, the hind tibia1 fringe predominantly whitish on the basal %. Abdomen pale yellowish above and below the dark mesa1 pair of lines faded brown, the sublateral ones obsolescent, with few black hairs in evidence. The mid-stripe broad, and widened on each hind border. The sublateral pale lines indistinctly step-like and irregular.
Westmoreland, Calif., July 20, 1933, M. Cazier. In the U. S. Nat71. Museum No. 56087.
Allotype, ? 12 mm. Head and its appendage shapes and eye pattern of the usual lineola type, frontal index 1:4.5, convergent below but parallel in the upper third. Callosity brown, narrowly separated from the eye margins, the me- dian callosity short and narrowly joined to the basal. Sub- callus yellow pollinose, face and cheeks whitish pilose and 2The unorthodox name was applied in manuscript on Dec. 8, 1941 (the day after "Pearl Harbor"), and is of barbaric derivation to com- memorate recent events associated with "Nippon", and a style of sneak air attack used even by horseflies.



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pollinose. Antennae red, scapes normal. Palpi pale yellow, attenuated, covered with pale hairs, and a few black ones on the apical segment. Thorax pale yellowish pilose and pol- linose above with 3 indistinct dark lines posteriorly, scutel- lum broadly pale reddish behind; pleurae, chest and cox= whitish pilose and pollinose. Wings hyaline, venation nor- mal. Halteres pale yellow. Legs pale reddish, fore pair brown on the inner faces of the femora and blackish beyond the middle of the tibiae, the hind-tibia1 fringe predominantly white on the basal two thirds. Abdomen very pale, incon- spicuously gray and reddish lined above, the pale middorsal line widened on each incisure, the sublateral gray lines ir- regular in a schwardti-like arrangement. Venter pale red- dish, with an indistinct, darker, mid-ventral band in certain lights ; black hairs only on terminal sternite. Westmoreland, Calif., 5-20-31, R. M. and G. E. Bohart. In the collection of the author through courtesy of Dr. T. H. G. Aitken.
Paratypes-3 8 , Westmoreland, Calif., July 20, 1933, M. Cazier ; 8, same data as allotype but May 15 ; 2 5, Coachella, Calif., May 13, 1917, E. P. Van Duzee;
8, Q, Brawley,
Imperial Co., Calif., Aug. 9, 1914, J. C. Bradley; Q , same data but Aug. 10; 3 8, same place May, 1911, June 1 and 6, 1912, J. C. Bridwell; 5, El Centro, Calif., June 25, 1917 (Bishopp No. 7392) ;
8, El. Centro, Calif., April; 4 5, $ ,
Sommerton, Ariz., June 2,
1938, C. C. Deonier (Bishopp
No. 27,815) ; 8 , Yuma, Ariz., April, 1937, R. M. and G. E. Bohart; 8, Ehrenberg, Ariz., Aug. 25, 1938, F. H. Parker. In the collections of the U. S. Nat'l Museum, Museum of Cornp. Zoology, T. H. G. Aitken, G. B. Fairchild, J. C. Bequaert, and the author. Part of these males were assigned to T. truquii Bell. by Stone (1938). There is some variation in size, and palpal shapes, while the upper eye facets in some males are contrasting yellow rather than brown. Four males from New Mexico and Texas appear to belong here because of the bleached body pattern, but approach schwardti in having darker shadows on the bases of the hind femora.
In south central California, where this intermingles with scutellaris, the latter also is somewhat pallid, and the fe- males are very close, but separated as given in the key. The



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34 Psyche [March- June
writer hesitated to describe this variant because of its like- ly extension into Mexico and the possible application of an earlier name. Lack of adequate Mexican material gives no assurance that this is not the case, but the form is distinct from any Neotropical material studied by me or by Fair- child.
Discovery of the correct male of vittiger is needed to jus- tify assignment of nippontucki as a subspecies. The fronts of the femalesand femoral colors are in agreement, but the wider, all reddish antennae, whitish hind tibia1 fringe, and different abdominal pattern with wide middorsal stripe (widened on the incisures somewhat as in maya Beq. and some other Neotropical species) may set this apart as more complete information is forthcoming. These remarks apply equally to differentiation from guatemalanus Hine which Fairchild also associates with vittiger. T. amplifrons Krober. The female from Brownsville, Texas, assigned to 7'. truquii Bell. by Stone (1938) has the parallel-sided front, small yellowish callosity, dark scutel- lum, reddish femora, and other characters of Krober's spe- cies, as well as of Hine's (1906) Guatemala truquii, and cer- tain other Neotropical specimens recognized by Fairchild. The associated males from Brownsville, Uvalde, and Gal- veston have hairy eyes with fairly uniform facets, but they show the peculiar contrast to the females of dark femora and somewhat enlarged scapes of Bequaert's (1940b) T. trilineatus and Hine's T. truquii. These sex differences are not in accord with other species of the lineola complex. I have also seen a confusing series of males from Gal- veston which differ only in having uniformly reddish legs and small antenna1 scapes. Whether these belong here or are a different variant is uncertain at present. There appears also a good possibility that an earlier name from among the now unplaced Neotropical ones eventually may be found to apply.
Separation of amplifrons, scutellaris, schwardti, and nippontucki still leaves a somewhat heterogeneous group of flies in lineola s. lat. which are susceptible of only unsatis- factory analysis in the absence (1) of unquestioned asso- ciation of males with divergent females, (2) of the real



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19421 Nearctic Tabaninz 35
identity in the restricted sense of Bellardi's3 and other per- tinent types, and (3) of definite information of what exten- sion from the Neotropical fauna has taken place through Mexico. In other words, while additional variants in the southern United Staates are still evident, any further res- triction of Nearctic "lineola" at the present time involves the danger of confusing, rather than clarifying the complex, except to point out such elements for reference for the future reviewer when adequate information is available. Among such observed elements divergent from lineola s. sir. may be mentioned the following.
Tabanus tr@ Bell. has been variously applied to hairy-