Type Specimens of the Small-Headed Flies (Diptera, Acroceridae) in the Collection of the Zoological Institute of the Russian Academy of Sciences, St. Petersburg

A catalogue of the types (holotypes, paratypes, and a lectotype) of the species of the family Acroceridae described by L.F. Hildebrandt, F.D. Pleske, and E.P. Nartshuk, deposited in the collection of the Zoological Institute, Russian Academy of Sciences, St. Petersburg, Russia, is presented. Photographs of the specimens and labels of the holotypes and lectotype are given.

In the present paper, the type specimens of the dipterans belonging to the family Acroceridae, deposited in the collection of the Zoological Institute of the Russian Academy of Sciences in St. Petersburg (ZIN), are considered.
The representatives of the family are medium-sized or large (2.5-20 mm) fl ies with tiny head and usually large spherical abdomen. In some fl ies (Oligoneura Bigot), the body is bent at a nearly right angle. The coloration is black, frequently with a white or yellow pattern against the black background. The family is distributed worldwide, except for the oceanic islands, and includes about 500 species in 48 genera. Approximately 40 species inhabit the Palaearctic Region, and 20 species mainly belonging to the genera Acrocera Meigen and Ogcodes Latreille are distributed in Russia (Nartshuk, 1988). The fl ies are rather rare in nature and, thus, are not numerous in the collections. Fossil representatives of the family are known since the Upper Jurassic. Four fossil genera and four species were described from Baltic amber. The adult fl ies are either nectarophagous with a long proboscis or do not feed. The larvae are endoparasites of spiders (Araneae) of the families Lycos idae, Theridiidae, and Gnaphosidae. Their de velopment lasts from several months to several years.
The lists given below include all the type specimens of the species from the ZIN collection. The species names are listed in alphabetic order and followed by the quoted labels of the type specimens, their inventory numbers, and current names of the species.
Most of the original labels are written in Russian. The labels cited below are transliterated and translated in English for the holotypes, and only translated for the other specimens.
The photographs were taken with a Canon EOS 800D camera with a MP-E 65 mm objective and clamped and processed by Helicon Focus 6 software.

FUNDING
The study was based on the collection of the Zoological Institute, Russian Academy of Sciences (project no. AAAA-A19-119020690082-8).

COMPLIANCE WITH ETHICAL STANDARDS
The authors declare that they have no confl ict of interest. All the applicable international, national, and institutional guidelines for the care and use of animals were followed. All the procedures performed in studies involving animals were in accordance with the ethical standards of the institution or practice at which the studies were conducted.

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