Interpopulation Variation of Leaf Polyphenol Content in Spiraea aquilegifolia (Rosaceae) from the Republic of Buryatia.

The composition and content of polyphenols in leaves was studied in Spiraea aquilegifolia Pall. plants from nine natural populations of the Republic of Buryatia (Western Transbaikalia) by high-performance liquid chromatography (HPLC). At least 24 compounds were detected in hydroethanolic extracts of S. aquilegifolia leaves by HPLC. Of these, three phenol carboxylic acids (chlorogenic, p-hydroxybenzoic, and p-coumaric acids) and six flavonols (hyperoside, isoquercitrin, avicularin, astragalin, quercetin, and kaempferol) were identified. Hyperoside (2.9-8.2 mg/g), avicularin (3.0-5.8 mg/g), and isoquercitrin (0.8-2.5 mg/g) were the main flavonols found in leaf hydroethanolic extracts. Plants from populations located at the northern distribution limit in Western Transbaikalia were found to have higher contents of phenol carboxylic acids (near the village Koma) and flavonols (near the village Klyuchi). Plants from populations located at the eastern limit (near the villages Kusoty and Zagan) showed the lowest concentration of the identified phenolic compounds. The contents of the identified free phenolic acids and flavonols were moderate or high in S. aquilegifolia leaves as compared to other Spiraea species examined, rendering it important to further study the composition of phenolic compounds in S. aquilegifolia.

New Materials on the Morphology of the Teeth of the Three-Toed Horse (Hipparion houfenense) from the Pliocene of Western Transbaikalia (Russia).

This article is devoted to the morphological features of the teeth of the three-toed horse (Hipparion houfenense) from the Early Pliocene of Western Transbaikalia (Russia). It contains a number of diagnostic features that are unique to this taxon and distinguish it from other Hipparion species, which allows us to speak about their true diversity at the final stage of their existence in the northeast of Inner Asia.

New Data on Dental Morphology of Hipparion tchicoicum Ivanjev, 1966 from Western Transbaikalia, Russia.

Morphological features of the teeth were studied in the three-toed horse Hipparion tchicoicum from the Pliocene of Western Transbaikalia (Russia). Several diagnostic signs of the Chicoi hipparion were described for the first time to provide criteria for distinguishing the taxon among other fossils of three-toed horses and estimating their real diversity at the final stage of their distribution in Inner Asia.

A Find of Early Pliocene Fossils of Three-toed Horse (Hipparion tchicoicum Ivanjev, 1966) in Western Transbaikalia.

This report analyzes a find of fossils of Pliocene three-toed horse (Hipparion tchicoicum) in western Transbaikalia. The age of the mammalian fauna from red-brown clay in the Udunga locality indicates that Chikoi hipparion lived in the south of Eastern Siberia as early as the second half of the Early Pliocene; its remains in this area were known only from the red beds of the Upper Pliocene. This find made it possible to fill the existing hiatus (Early Pliocene) in its stratigraphic distribution: Late Miocene-Late Pliocene. The range of this three-toed horse species did not go beyond the borders of northern China, northern Mongolia, and the south of Eastern Siberia, which suggests its evolution within Inner Asia.