Tatiana M. Tiunova

Biodiversity and distribution of mayflies (Ephemeroptera) in the Russian Far East

Twenty-five years of investigations on the distribution and taxonomy of the mayflies in the Russian Far East has resulted in the records of 170 species belonging to 39 genera and 16 families. Original findings of mayflies in tributaries of the Sea of Japan, the basin of Ussuri, and Amur Rivers are presented. Most of the recorded species inhabit East Palaearctic and Palearchearctic areas. A list of all species found in the Russian Far East is given.

A new species of Torleya Lestage, 1917 (Ephemeroptera: Ephemerellidae) from the Far East of Russia

A new species Torleya mikhaili is described from the larvae and a reared male imago. The male and female imagines of Torleya padunica Kazlauskas are described.

A NEW SPECIES OF SYMBIOCLADIUS KIEFFER, 1925 (DIPTERA: CHIRONOMIDAE: ORTHOCLADIINAE) FROM THE EASTERN PALAEARCTIC

The adult male, pupa, and fourth instar larva of Symbiocladius (s. s.) villosus Makarchenko et Makarchenko, sp. n. from the Russian Far East and Japan are described and figured. Adult male of a new species separated from all known species of subgenus by presence of a pair rodshaped chitinized structures which situated above apical parts of phallapodemes, and is closely related to the Palaearctic species S. (s. s.) rhithrogenae and the Nearctic S. (s. s.) chattahoocheensis. S. (s. s.) villosus sp. n. can be distinguished from the first species by shape of gonostylus which expands from the base to the middle and with longer and more numerous setae. From S. (s. s.) chattahoocheensis a new species can be separated by roundish-triangular dorsal part of inferior volsellae and presence of 2 megasetae on gonostylus.

New species of Ameletus Eaton, 1885 from the Russian Far East with notes on Ameletus camtschaticus Ulmer 1927 (Ephemeroptera: Ameletidae)

The male imagoes, larvae, and eggs of Ameletus allengaensis sp. nov. and Ameletus sirotskii sp. nov. from the Russian Far East are described. Based on the structure of the male genitalia, the imago and larvae of A. allengaensis sp. nov. and A. sirotskii sp. nov. are similar to those of A. camtschaticus, but the discovery of these new species and separation from A. camtschaticus were confirmed by studies of the morphology of the larvae and male imago, as well as molecular analysis. Identity of various developmental stages of the new species were confirmed by analysis of the mitochondrial gene cytochrome oxidase 1 (COI) DNA barcode, which was also used to reconstruct the phylogenetic relationships within the genus Ameletus. The intraspecific sequence divergence based on the Kimura-2-parameter (K2P) distance ranged from 0.0-2.5%, whereas the interspecific sequence divergence based on the K2P distance ranged from 6.2-7.9% within A. sirotskii sp. nov., A. allengaensis sp. nov. and A. camtschaticus. Male imagoes of A. allengaensis sp. nov., A. sirotskii sp. nov., and A. camtschaticus can be distinguished by the size and location of small denticles on the ventral plate of the penis. The larvae of A. allengaensis sp. nov. differ from those of A. sirotskii sp. nov. by the size of gills I and II. In A. allengaensis sp. nov., gill I is almost twice as small as gill II; in A. sirotskii sp. nov., gill I is only slightly smaller than gill II. Both new species differ from A. camtschaticus by gill II, which does not have an anal rib on the anal margin.

A new species of Paraleptophlebia Lestage, 1917 (Ephemeroptera: Leptophlebiidae) and a re-description of adults for Paraleptophlebia westoni Imanishi, 1937 with the first description of the larva, from the Russian Far East

Male, female imagoes and eggs of Paraleptophlebia kunashirica sp. nov. and the larva, male and female imagoes of Paraleptophlebia westoni are described based on material from the Russian Far East. Comparison of the male imago of Paraleptophlebia kunashirica sp. nov. and the larva and male imago of Paraleptophlebia westoni with other known larvae and imagoes of Paraleptophlebia are given. Paraleptophlebia westoni larvae may be distinguished from congeners by characters associated with the mouthparts, such as the ratio of the length of the maxillary and labial palp segments, shape of hypopharynx, and structure of the claw. Male imagoes of Paraleptophlebia kunashirica sp. nov. and Paraleptophlebia westoni сan be distinguished between themselves and other representatives close to them in the form of the ventral appendages and the apex of the penis lobes.