First data on the mites (Mesostigmata, Oribatida) from sea debris of the Caspian Sea (Dagestan coast, Russia)

Mites in seaweeds from two distant sites of the Dagestan State Nature Reserve, namely from the Kizlyar Bay and Samoor Forest, were studied. Total of 31 species of mesostigmatic mites (Acari: Mesostigmata) and 31 species of oribatid mites (Acari: Oribatida) were collected and identified. The other mites (Astigmata, Prostigmata, and Endeostigmata) belong to 19 families. One species of gamasid mites [Gamasellodes vulgatior (Athias-Henriot, 1961)] and two species of oribatids [Austrophthiracarus cf. duplex (Mahunka & Mahunka-Papp, 2010); Xenillus moyae Pérez-Íñigo & Peña, 1994] are recorded from Russia for the first time. Among 62 identified species, 28 (including the majority of Mesostigmata) were not previously recorded in Dagestan. The faunistic similarity of species lists from two sites was only 13.1% (Jaccard's coefficient). The input of broadly hydrophilic mite species (15% of the total list) is noticeable. However, no characteristic halophilic (littoral) species were found. Most likely, this is due to the absence of marine macrophytes (and their emissions) in studied soft-ground coastal areas. It is during their decay that a specialized saprophilic complex of invertebrates is commonly formed.