Bactria ovczinnikovii (Czukavina, 1962) Yurtseva & Mavrodiev

Yurtseva, Olga V. & Kostina, Marina V., 2024, Flower arrangement and plant architecture in Atraphaxis, Bactria, and Persepolium (Polygonaceae, Polygonoideae, Polygoneae) and their systematic implications, Phytotaxa 671 (1), pp. 12-58 : 46

Bactria ovczinnikovii —early flowering

Bactria ovczinnikovii is endemic to Southern Tajikistan (specifically, the Khatlon region, Shuroabad district, village Bag). This area has a semi-arid (Mediterranean) climate with hot, dry, rainless summer ( Kasirov 2006, Yurtseva et al. 2019). In Köppen climate classification, it is Bsk, or cold steppe-desert climate ( Kottek et al. 2006, Arnfield 2016). The annual precipitation is ca 500 mm.

The plants have a Type I shoot system formed by orthotropic reproductive shoots with a rather long innovation zone and a short frondo-bracteose thyrse, which stops the growth after the formation of few cymes. Perianths are rather inconspicuous. Due to acro- and mesosympodial growth of innovation shoots, the plants are dwarf shrubs ( Yurtseva et al. 2016a: Supplementum 10). The early flowering from April to June, before the summer drought, is the only adaptation to arid conditions, which suggests that this species originated in a milder variant of Mediterranean climate.