![Sample our Environment & Agriculture journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5934/TOC-Subject-Sample-2021-Environment-Agriculture.jpg"})
Abstract
Contribution Number 000 of the Great Lakes Research Division
Light microscopical observations were made on material from Lake Baikal containing Gomphoneis quadripunctata (Østr.) Dawson ex Ross & Sims. The material had originally been used by Skvortzow to describe many subspecific taxa of this species. The many forms present all have multiple stigmoids positioned around the central area, septa at both poles, and undifferentiated apical pore fields. From the large number of taxa identified by Skvortzow, three species are recognized: G. hastata (Wisl.) Kociolek & Stoermer, comb, nov., G. tumida (Skv. in Skv. & Meyer) Kociolek & Stoermer, comb, nov., and G. quadripunctata. Species were segregated by differences in initial valve length and corresponding variation in valve shape and morphology. Of the three species recognized, G. hastata and G. tumida possess longitudinal lines in girdle view, while in G. quadripunctata such lines are absent. Relationships of these three species to G. olivaceoides (Hust.) Carter & Bailey-Watts and other Gomphoneis species are discussed.