Smithsonian Miscellaneous Collections

SMITHSONIAN MISCELLANEOUS COLLECTIONS PART OF VOLUME LI THE TAXONOMY OF THE MUSCOIDEAN FLIES, INCLUDING DESCRIPTIONS OF NEW GENERA AND SPECIES CHARLES H. T. TOWNSEND, B. Sc. In Charge of Collections of Muscoidean Flies, U. S. National Museum «ti^ WA'% fc No. 1803 CITY OF WASHINGTON PUBLISHED BY THE SMITHSONIAN INSTITUTION 1908 f \\evrhinoton' J THE TAXONOMY OF THE MUSCOIDEAN FLIES, IN- CLUDING DESCRIPTIONS OF NEW GENERA AXD SPECIKS By CHARLES II. T. TOWNSEND, B. Sc. History When we review the history of the classification of any highly specialized group of insects, provided it has attained a considerable degree of popularity among systematists, we find it to exhibit a well-marked series of oscillations between the two extreme- com- monly known as bunching" and splitting. This is especially true of the dipterous superfamily Muscoidea. 1 The systematists of the eighteenth and nineteenth centuries, ac- cording to the work they did on this superfamily. mark alternate periods of action and reaction which fall conveniently into five his- torical epochs. Linne, Fabricins, and Latreille must be considered the pioneers. The system they established was followed by their immediate' contemporaries. Very few others concern us here, but Geoffroy erected the genus Stomoxys. and Scopoli, Rossi, and Panzer did some work on the superfamily. As a natural result of approaching a quite new subject, these early workers did not always grasp the real value of characters. Largely because of the comparative dearth of material in those initial days of systematic work, they did not clearly discern anatomical values, and hence did not recognize many characters whose worth has since been well established. Meigen introduced a new epoch in 1804, and considerably increased the number of genera by splitting up the original ones established by his predecessors. Collections had become richer in mate- 1 It is to be noted that the superfamily Muscoidea, as herein restricted, includes but a portion of the forms to which the name was applied by it- author, Mr. D. W. Coquillett. As now restricted, it includes practically the old calyptrate Muscidae minus the Anthomyiidse, or the same group as that treated by Brauer and von Bergenstamm— Muscaria Schizometopa, exclusive Antho- myiicke. The Muscoidea is here divided into live families a- follows: (1) CEstridse, (2) Macronychiida? (being a part of the old Dexiidae), (3) Tachi (including the old Gymnosomatidae, Phaniidae, Ocypteridae, Sarcophagidae. and most of Dexiidae as subfamilies). (4) Muscidae, and (5) Phasiidae (including Rutilia and its allies). 1 1 2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 5 rial by this time, and Meigen's attention was naturally drawn to the discovery of further characters that could be used in classification. He was indorsed and followed by his contemporaries, Olivier, Fallen, Say, Wiedemann, who adopted his genera without proposing new ones, except that the last-named author erected the single genus Glossina for the tse-tse flies. Dumeril erected the genus Bchiiwmyia, and Le Peletier de Saint-Fargeau the single genus Prosena. Mei- gen's best work was in genera. His descriptions of species were in many cases faulty. On the whole, however, he is clearly to be looked upon as an epoch-maker. The first really intuitive student of the superfamily was Robineau- Desvoidy who. in 1830. introduced the third epoch and very greatly increased the number of genera, besides defining more or less natural taxonomic divisions for their reception. It must be understood that very considerable accumulations of material from the Americas, both North and South, had reached Europe during the early part of the nineteenth century, besides much material from the African, Ori- ental, and Australasian regions. To most of this Robineau-Desvoidy had access. Notable among the accumulations were the rich collec- tion of the Count Dejean, which had been added to constantly by Latreille, and the quite extensive material secured from all parts by the Museum of the Jardin du Roi in Paris. Palisot de Beauvois, Saint-Hilaire, Bosc, and many others collected in the Americas, and various representatives of the Jardin du Roi in other parts of the world. Besides these, many European entomologists sprang up who began to do much more thorough collecting at home. Thus a comparatively great wealth of material in the Muscoidea was brought together from all parts of the world, both at home and abroad, which stimulated Robineau-Desvoidy to a detailed study of characters in this superfamily. His "Essai sur les Myodaires" remains to this day a monument to his very considerable grasp of Muscoidean relationships. His posthumous work (1863) can not be considered as affecting in any way the status of the "Essai." Macquart, almost contemporaneous with Robineau-Desvoidy, but possessed of less discernment, bunched the latter's genera to a very considerable extent. However, it must be pointed out in defense of Macquart that he was eminently a general dipterist, while Robineau- Desvoidy was preeminently a specialist in the Myodaria. Zetterstedt erected only two genera in the superfamily, and practically employed Meigen's genera for all of his work. Perty, Bouche, Guerin, and Bremi each erected a single genus in the superfamily. Robineau-Desvoidy's system, founded largely on habits, was in a degree faulty and insecure. Attention should be called to the fact, TAXONOMY OF MUSCOIDEAN FLIES—TOWNSEND 3 apparently long- since lost sight of, that Robineau-Desvoidy origi- nated the idea of including the CEstridae with his Calypterata (al- though renounced in his posthumous work), and the Conopidse with the Myodaria (Conopidae not included at all in posthumous work). The founding of the now obsolete division Calypterata is also to be accredited to him, though it is to be noted that he did not include the Anthomyiidas therewith. The latter family was included in that division by subsequent authors. In this connection, see Osten- Sacken for statement that the term "Acalypterata" was interpolated in Robineau-Desvoidy 's posthumous work by the editors (Berl. Ent. Zeit, 1896, pp. 329, 335-6). Rondani marked a fourth epoch beginning about 1850. He re- vised in large part the work of Robineau-Desvoidy,' still further increased the number of genera, was altogether a very close student of relationships, and possessed a remarkably clear insight into the affin- ities of the Muscoidea, in which he was essentially a specialist. His system was followed to some extent by his more immediate contemporaries, but Schiner, with a fine grasp of dipterous characters in general and little conception of the needs of the Muscoidea, was especially active in bunching his genera. Schiner was a splendid general dipterist, but the method of treatment adapted to other groups of Diptera fails when the attempt is made to apply it to the Muscoidea. That is where Schiner, Mac- quart, and all the other conservatists fell. And it is to be noted that these conservatists were always general dipterists. They tried to apply the same system throughout the Diptera, but the Muscoidea need a distinct method of treatment, as will appear further on in this paper under that heading. Even such conscientious students as van der Wulp, Loew, Osten-Sacken, Williston, and others, who followed Schiner largely, but were somewhat less conservative than he, nevertheless fell far short of reaching a requisite degree of radicalism in their views as to a proper treatment of this superfamily. Others who entered the ranks during this fourth epoch, Walker, Bigot, Bellardi, Jaennicke, Thomson, Meade, von Roeder, Kowarz, Mik, followed Schiner more or less, adopting Rondani and Rob- ineau-Desvoidy at times on certain points, and gradually increased the stock of genera as seemed warranted along more or less conservative lines. Robineau-Desvoidy had divided the Muscoidea into many smaller groups which he called stirpes, corresponding more or less in value to our present subfamilies. These were not recognized by Rondani, who grouped all into six stirpes. Neither Robineau-Desvoidy nor Rondani were really adopted by Schiner, who recognized eight 1 4 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 5 stirpes, mainly founded, however, on certain of Robineau-Desvoidy's. Schiner thus largely adopted Robineau-Desvoidy's stirpes in those divisions which he did recognize, but bunched his genera along with those of Rondani, Robineau-Desvoidy's reviser. The eight taxonomic divisions adopted by Schiner generally obtained throughout the epoch. Rondani's system, unlike Robineau-Desvoidy's, took little note of habits, and, while less detailed, was more secure from being founded primarily on external anatomical characters. But these characters were liable to misinterpretation in certain cases. Brauer and von Bergertetarnm inaugurated the present and fifth epoch in [889, which is destined to hold out for a greater degree of radicalism than its predecessors. They approached the subject largely in a new way, greatl) lessening the difficulties of classification in the superfamily by recognizing a large number of sections which correspond to the subfamilies and tribes of the present paper. At the same time, they greatly multiplied the number of genera, whereby they were able to present comparatively concise diagnoses of these, as well as of their sections. They adopted Robineau-Desvoidy's plan of grouping the forms into many small divisions, hut they did not feel hound, as did he, to adhere to any definite scheme

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