J. Bequaert.
Notes on Hippoboscidæ. 2. The Subfamily Hippoboscinæ.
Psyche 37:303-326, 1930.

Full text (searchable PDF, 2224K)
Durable link: http://psyche.entclub.org/37/37-303.html

The following unprocessed text is extracted from the PDF file, and is likely to be both incomplete and full of errors. Please consult the PDF file for the complete article.

PSYCHE
VOL. XXXVII DECEMBER, 1930
No. 4
NOTES ON HIPPOBOSCIDAE
Department of Tropical Medicine,
Harvard University Medical School
Although much has been written concerning some of the common species of Hippobosca that infest equines and cat- tle, no comprehensive and critical account of the genus as a whole has been published thus far. The present attempt at filling this gap cannot be more than prelimi- nary, especially with regard to the synonymy adopted for the many names proposed in this group. In no case have I had access to the types on which these names were based. The genus Hippobosca occupies an isolated position in the family Hippoboscidse, forming a subfamily of its own, which was first defined by Speiser (1908, Zeitschr. Wiss. Insektenbiol., IV, p. 445).
Subfamily Hippoboscinae
Head rounded posteriorly, entirely free from the anterior margin of the thorax.
Antenna1 pits completely enclosed
by a continuous rim, containing the small, subglobular antennae, which have no dorsal prolongation. No ocelli.
Pronotum well developed dorsally, visible between the head and the mesonotum. Humeral angles rounded off, not projecting. Claws simple, but apparently bidentate, with- out supplementary tooth between the sharp apex and the 1,




================================================================================

304 Psyche [December
broad, flattened "heel" of the base.
Wings always well
developed and functional throughout adult life; six distinct longitudinal veins and a vestigial seventh vein between the fifth (M3+Cui) and sixth (An) ; two cross-veins, the an- terior (r-m) and the anterior basal (m-cu or M3) ; second basal cell very long; no closed anal cell; membrane bare, but rilled with numerous delicate, more or less parallel wrinkles, extending from the region of distinct veins toward the hind margin.
The subfamily contains only one genus.
Hippobosca Linnseus
Hippobosca Linnaeus, 1758, "Syst. Nat.," 10th Ed., I, p. 607 (type: Hippobosca equina Linnaeus, 1758, designated by Latreille, 1810, Consider. Gener. Crust. Arachn. Ins., pp. 407 and 444).
Hippobosca subgenus Nirmomyia Nitzsch, 1818, in Germar's Mag. d. Entom., 111, p. 309 (monotypic for Hippobosca equina Linnaeus, 1758).
Zoomyia Bigot, 1885, Ann. Soc. Ent. France, (6) V, pp. 227 and 234 (tentatively proposed as a substitute for Hippo bosca; type by present designation : Hippo bosca equina Linnseus, 1758).
Attention may be called to the remarkable structure of the pulvilli and empodium, which in this genus offer excel- lent specific characters.
The genus Hippobosca is indigenous throughout the con- tinental areas of the Old World.
All of the eight species,
which I recognize as valid, are found in Africa; four of them extend also into the Oriental Region and two have entered Europe. Much of the present distribution of H. equina, H. camelina, H. rnaculata, and H. capensis is un- doubtedly artificial and due to the spreading of their domes- tic hosts by man. I have tried to trace the probable original home of these species, but the conclusions I have reached



================================================================================

19301 Notes on Hippoboscidas 305
are far from satisfact0ry.l None of the species appear to have become naturalized in the New World, where their occurrence is very accidental.
With one exception, the species of Hippobosca are ecto- parasites of mammals, mainly of Ungulates and Carnivora. H. struthionis, however, is a normal parasite of the ostrich. Since the Ungulates and Carnivora were more numerous and more widely distributed in Mesozoic times than nowa- days, it is safe to assume that Hippobosca has had a long geological past and may have been at one time cosmopoli- tan. The few living species are perhaps only the rem- nants of a large group of parasitic flies, which may have been as numerous in species as the living Hippoboscidse of birds.
The Hippoboscse are fairly good fliers. The gravid female leaves the host and deposits the full-grown larva in cracks of walls, in holes of trees, or on the ground. Patton, for instance, observed a female of H. capensis leave a dog, fly onto a wall and, after running along it, rapidly disappear into a crack. The fly remained there a few minutes; as it emerged, it was caught, and, on examining the crack, a larva was found a little distance inside (Patton and Evans, 1929, "Insects, Ticks, etc., of Medical and Veterinary Im- portance," I, p. 404) .2
Host specificity is not very pronounced among the Hip- poboscidse which retain the wings throughout adult life, and this statement applies particularly to Hippobosca. Only the species of the ostrich seems to be restricted to a single host-species. H. fulva, H. hirsuta and H. camelina also have a narrow range of normal hosts. The other species have nowadays a variety of usual hosts; but in some cases this may be an artificial condition, due to the influence of man. Spreading of certain species by man beyond their There is a voluminous literature dealing with the ancestors of domestic animals. After consulting a number of publications, I have found what appears to be the most reliable information in Keller, Conrad, 1902. "Die Abstammung der altesten Haustierel," (Zurich), 232 pp.
1 have not found any evidence that the puparia of Hippobosca are ever placed among the fur or feathers of the host, as Theobald (1906, 2d Rept. Wellcome Res. Lab. Khartoum, p. 92) has claimed.



================================================================================

306 Psyche [December
original home may perhaps explain partly why more than one species of Hippobosca infest nowadays domestic equines and cattle. I have attempted to distinguish in a table between the "normal" and the "facultative" or "a~cidental'~ hosts, in so far as feasible.
Normal Hosts Facultative and
Accidental (Ace.)
Hosts
Hi fulva
H. maculata
H. rufipes
H. hirsuta
H. struthionis
H., camelina
domestic equines
domestic dog, lion,
leopard, h y e n a ,
cheetah, civet, fox,
serval
hartebeest
domestic equines
and cattle
domestic equines
waterbuck and al-
lied antelopes
ostrich
camel, dromedary
cattle
(Ace. : dog, rabbit,
camel, birds)
duiker, dik-dik
(Ace. : mule)
camel, dromedary
domestic c a t t 1 e ,
wildebeest, e 1 a n d ,
giraffe
(Ace. : ? ostrich)
horse ( ? Acc.)
The following alphabetical list of 36 names will serve as an index to the synonymy here adopted: albo-maculata Macquart=rufipes v. Olfers. albonotata Rondani=ru/wes v. Olfers.
bactriana Rondani=cameIina Leach.
bengalensis Ormerod=maculata Leach.
bipartita Macquart=macu~lata Leach.
calopsis Bigot=maculata Leach.
cameli Leach=camelina Leach.
8. camelina Leach. A valid species.
camelopardalis Roubaud=rufipes v. Olfers. canina Rondani=capensis v. Olfers.




================================================================================

19301 Notes on Hippoboscidas 307
2. capensis v. Olfers. A valid species.
chinensis Giglioli=capensis v. Olf ers.
cunicosa Thalhammer=capensis v. Olfers.
dromedarina Speiser=cam,elina Leach.
egyptiaca Macquart=macdata Leach.
equi Macquart=epina Linnaeus.
1. equina Linnaeus. A valid species.
f ossulata Macquart=maculatu Leach.
francilloni Leach=capensis v. Olfers.
3. fulva Austen. A valid species.
6. hirsuta Austen. A valid species.
laticornis Macquart=capensis v. Olfers.
longipennis Fabricius=probably capensis v. Olfers. 4. maculata Leach.
A valid species.
maculata Macquart=rujipes v. Olfers.
marginata v. d. Wulp=rufipes v. Olfers.
massaica Speiser==struthionis Janson.
neavei Austen=hirsuta Austen.
orientalis Macquart=capensis v. Olfers.
5. rufipes v. Olfers. A valid species.
sivas Bigot=macdata Leach.
7. struthionis Janson.
A valid species.
sudanica Bigot=maculata Leach.
taurina Rondani=equina Linnaeus.
variegata Wiedemann===waculata Leach.
wahlenbergiana Jaennicke=rufipes v. Olfers. I have studied specimens of the seven valid species sepa- rated by the subjoined key, which I have attempted to base mainly upon reliable structural characters. I have found that the coloration, although often helpful, is rather varia- ble in certain species, and I do not regard it as of specific value when no differences in structure can be discovered. Hippobosca fulva Austen appears to be distinct from the other seven. I have not seen it, and the characters given in the description do not allow of its being included in my key.




================================================================================

308 Psyche [December
1. Second longitudinal vein (R24) long, reaching the costa much beyond the tip of the first longitudinal (Ri) and apicad of the anterior cross-vein; the last section of the costa at most three times the length of the penulti- mate section. Base of third longitudinal vein (R4+5) bare. One pair of vertical bristles. Two pad-like pulvilli at the sides of the bristle-like empodium, one much larger than the ot.her .................................... 2
Second longitudinal vein short, reaching the costa to- gether with or close to the tip of the first longitudinal; the last section of the costa equal to at least five times the distance between the tip of the first and that of ..................................
the second longitudinal veins 3
2. Apical lobes of the fronto-clypeus regularly and sharply triangular, their inner margins nearly straight. Scu- tellum as a rule wholly ivory-white; wing veins mostly pale testaceous, with some darker stretches. Smaller, the wing 5 to 6 mm. long ............................... .H. capensis Apical lobes of the fronto-clypeus irregularly and broadly triangular, their inner margins curved. Scu-
tellum fuscous to ferruginous on the sides, yellowish white in center, rarely more extensively yellowish ; wing veins as a rule rufous to dark brown. Larger, the wing 6 to 8.5 mm. long ........................... .H. equina 3. Base of third longitudinal vein setulose over some length on the upper side. One pair of vertical bristles. Only one pulvillus well developed, the other rudimentary 4 Base of third longitudinal vein bare ........................ 6 4. Second longitudinal vein very short, forming an oblique cross-vein which ends in the first longitudinal and runs from opposite or apicad of the upper tip of the ante- rior basal cross-vein to basad of the anterior cross- vein. Scutellum as a rule with three ivory-white spots, the largest in the center; bristles of head and thorax pale. Large, the wing 7 to 8 mm. long ... H. maculata Second longitudinal vein much longer and more oblique, ending in the costa close to or at the tip of the first longitudinal and running from basad of the upper tip of the anterior basal cross-vein to opposite or basad of the anterior cross-vein ............................................ 5



================================================================================

19301 Notes on Hippoboscidse 309
5. Vertex distinctly narrower at the occiput than at the fronto-clypeus in both sexes. Scutellum very wide and nearly rectangular, with a median, rufous, and two lateral, ivory-white spots. Legs bright reddish ; bristles of head and thorax brownish black. Larger, the wing 7 to 9 mm. long .............................. H. rufipes Vertex about as wide at the occiput as at the fronto- clypeus. Scutellum narrower and less rectangular, with a median, ivory-white spot. Legs rufous-yellow ; bristles of head and thorax pale.
Smaller, the wing
6.5 to 8 mm. long ............................................ H. hirsute, 6. Two pairs of vertical bristles.
Sclerotized upper plate
of vertex (or vertical triangle) about as long as wide at the occiput, much shorter than the medio-vertex, the latter considerably narrowed in the middle by the very broad inner orbital plates. Apical lobes of fronto- clypeus broadly separated by a semi-elliptical notch. Second longitudinal vein ending in the tip of the first, opposite the anterior cross-vein. Anterior basal cross-vein very oblique and nearly its own length from the anterior cross-vein. Scutellum semi-elliptical in outline, its posterior margin distinctly convex and slightly projecting in the middle. No pad-like pulvilli ; the bristle-like empodium bare, except at the base. ............ Larger, the wing 9 to 10 mm. long H. camelina
One pair of vertical bristles.
Sclerotized upper plate
of vertex longer than wide at the occiput, as a rule longer than the medio-vertex, the latter moderately narrowed by the inner orbital plates. Apical lobes of the fronto-clypeus separated by a narrow notch. Second longitudinal vein reaching the costa close to the tip of the first and apicad of the anterior cross- vein. Anterior basal cross-vein short, almost vertical upon the fourth longitudinal and more than twice its own length from the anterior cross-vein. Scutellum subrectangular, broadly truncate at the apical margin, not projecting in the middle. Two pad-like pulvilli; the empodium feathered. Smaller, the wing 7 to 7.5 .................................................... mm. long H. struthionis




================================================================================

310 Psyche
[December
1. Hippobosca equina Linnaeus
Hippobosca equina Linnaeus, 1758, "Syst. Nat.," 10th Ed., I, p. 607 (no sex given; Europe and North America). Austen, 1906, "Illustr. Brit. Blood-Suck. Flies," p. 63, PI. XXXI. Newstead, Dutton and Todd, 1907, Ann. Trop. Med. Paras., I, p. 90, figs. 17 ( Q ) and 18 (pupa- rium) . Schuurmans-Stekhoven, 1926, Parasitology, XVIII, p. 49, PI. IV, figs. 3 and 4 ( Q 8 ). Hippobosca equi Macquart, 1835, "Hist. Nat. Ins. Dipt.," 11, p. 638, PI. XXIV, fig. 8 (error for H. eqzdna). Hippobosca taurina Rondani, 1879, Boll. Soc. Ent. Italiana, XI, pp. 24 and 25 (no sex given; off cattle in central Italy).
SPECIMENS EXAMINED.-SW~~~~ : (Ljungh) . Germany : Berlin. Spain : Montanegos (Cevera) ; Escurial ; Iviza, Baleares ; (W. M. Wheeler). France: Banyuls-sur-Mer, Pyr. Or., off a dog (G. Dimmock). Sardinia : (Krausse) . Turkey: Reshadie (H. R. Hagan). Egypt: (S. H. Scud- der). New Caledonia: Plum Farm (T. D. A. Cockerell). Belgian Congo : Kitobola, two males, 1913 (Rovere). Phil- ippines: Manila (M. J. Myers).
DISTRIBUTION.-T~~S common species is known in Eng- land as the "forest-fly," after the New Forest in Hamp- shire, where it is particularly abundant. It may have been at first restricted to southern Europe and western Central Asia; but nowadays it is found throughout Europe (as far north as Lapland, and also in the British Isles), North- ern Africa (as far south as Biskra), the Canary Islands, Madeira, the Azores, the Senegal, the Anglo-Egyptian Sudan, Egypt, Palestine, Asia Minor, India, the Sunda Islands, the Philippines, Celebes, Fiji, the New Hebrides and New Caledonia (introduced about 1890). It has been seen on freshly imported horses in Australia, but it does not seem to have become established there. Linnaeus (1758) mentioned North America as part of the habitat and Loew [1864, Amer. Jl. Sci. Arts, (2) XXXVII, p. 3181 included



================================================================================

19301 Notes on Hippoboscidse 311
it among the species of Diptera common to Europe and America. It is doubtful, however, whether either Lin- nseus or Loew actually saw American specimens. Loew's
record may have been based upon the earlier statement by W. Kirby (1837, Fauna Boreali-Americana, IV, p. 317; see Bethune, 1881, Canad. Entom., XIII, p. 169), who listed H. equina among the insects of Boreal America, with- out, however, mentioning a definite locality. Notwith- standing certain discrepancies, Kirby's description seems to have been based upon a specimen of true equina; but whether or not it came from North America is open to question. In any case, no other entomologist seems to have reported this fly from a New World locality, and I have never seen an authentic American specimen in any collection. Moreover, it is somewhat of a mystery why this fly has not become established in America, since it must have been brought over repeatedly from the Old World.
Newstead, Dutton and Todd (1907) {state that they saw a few examples of H. equina on cattle, shipped at Las Palmas, Canary Islands, while on board ship on their way to the Belgian Congo. But the two specimens which I have seen from Kitobola are the only ones actually taken in tropical Africa, where H. equina seems to be replaced by H. maculata. Walker (1849, "List Dipt. Brit. Mus.," IV, p, 1140) includes the Cape Colony in the range of the species, but no specimens have since been taken in South Africa.
HOSTS.-H. equina is usually found on equines (horses, mules and donkeys), sometimes also on cattle and more rarely on dogs, rabbits, or camels. Accidentally it may stray to birds. Massonat (1909, Ann. Universite Lyon, N. S., CXXVIII, p. 242) saw specimens from owls (Tyto flam- mea) and from a kite (Milvus regalis), and Schuurmans- Stekhoven captured one on a pigeon. It is of interest that this species has never been taken on the wild equines of Africa.
The predilection which H. equina shows for horses makes it very probable that this insect was originally a specific parasite of one of the wild horses from which the domestic



================================================================================

312 Psyche [December
races have been derived. According to C. Keller (1902), the ancestor of the heavy races of horses was a wild equine which lived in Europe during the Pleistocene (Equus cabal- lus Linnaeus) and even survived until historic times. The lighter races, on the other hand, had an Asiatic origin and were most probably derived from Equus przewalskii Poli- akoff, a wild equine of Central Asia, of which a few speci- mens may be living yet in a feral state in Dzungaria. I am inclined to the view that both these ancestral species were infested with H. equina, although, of course, this is a mere hypothesis. It may yet be possible to find the insect on the living E. przewalskii.
AFFINITIES.-H. equina and H. capensis appear to be very closely allied, although there can be no doubt that they are specifically distinct. After a very careful study, I have found that the only structural difference, which seems to be entirely reliable, is found in the shape of the fronto-clypeus. I had thought at first that the wing vena- tion afforded some additional distinctive features. The relative distance from the tip of the second longitudinal vein to that of the first and third longitudinals appears to be highly variable. The length of the anterior basal cross-vein (or second basal cross-vein; m-cu or &) is per- haps more reliable: in H. capensis this cross-vein is fairly . straight and, as a rule, about as long as the distance from its tip to the anterior cross-vein (r-m) ; in H. equina it is more curved and generally much longer than the dis- tance from its tip to the anterior cross-vein. In one male of H. eqzdna, from Sardinia, the left wing has a double anterior cross-vein, enclosing a small super- numerary cell ; the right wing is normal. A further specific character may perhaps be found in the size and shape of the sclerotized upper plate of the vertex (vertical triangle). In all the 29 specimens of H. equina examined, this plate occupies about the upper third of the vertex, being at most half the length of the medio-vertex (or frontalia) ; it is almost semi-circular in outline and much wider at the occiput than long on the middle line. In most of the specimens of H. capensis seen,



================================================================================

19301 Notes on Hippoboscidse 313
this upper vertical plate is much more extensive, being over half the length of the medio-vertex, sometimes occu- pying nearly half of the vertex; it is rather semi-elliptical and only a little wider at the occiput than long on the middle line. Unfortunately I have seen several specimens of H. capensis which in the shape of the vertex do not appreciably differ from H. equina. Nevertheless, this char- acter may be of specific value, even though its variability prevents its being used in a key.
The color peculiarities of the scutellum and of the vena- tion, which have been generally used as specific characters, I have found to be extremely variable and wholly unreliable in these two species. I have seen specimens of H. equina colored almost exactly like H. capensis, and I am certain that the two have often been confused in collections. 2. Hippobosca capensis v. Olfers
Hippobosca capensis v. Olfers, 1816, "De Vegetativis et Animatis Corporibus in Corpor. Anim. Reper. Comm.," I, p. 101 (not seen).
Hippobosca francilloni Leach, 1817, "Gen. Spec. Eprobosci. Ins.," p. 8, PI. XXVI, figs. 8-10 (no sex given; with- out locality). Theobald, 1906, 2d Rept. Wellcome Res. Lab. Khartoum, p. 92, figs. 51 and 53C; PI. X, fig.