Untersuchungen über baltoskandische Asaphiden III. Über die Gattungen Megistaspis n. nom. und Homalopyge n. gen.

The new generic name Megistaspis n. nom. is substituted for Megalaspis Aangelin June 1851 (non Megalaspis BLEEKER, May 1851). The three groups of species within the genus Megistaspis, recognized already by Fr. Schmidt (1906), are treated as separate subgenera. Besides the nominate subgenus Meg. (Megistaspis) (type: Trilobites limbatus Boeck, 1838) a new subgenus Meg. (Megistaspidella) (type: Entomostracites extenuatus Wahlenberg, 1821) is erected. For the third group of species (the Megistaspis planilimbata group) no subgeneric name is proposed as complementary studies are needed before this subgenus can be defined. Three new specific names are proposed for junior homonyms within the subgenus Meg. (Megistaspis), viz. Meg. (Megistaspis) lepikuensis n. nom., Meg. (Megistaspis) laine n. nom., and Meg. (Megistaspis) ingeriensisi n. nom. The examination of the lectotype of Trilobites limbatus Boeck, 1838, has proved it to be specifically distinct from the species hitherto determined as Megalaspis limbata. It is suggested that the genus Plesiomegalaspis Thoral, 1946, be regarded as a subgenus of Kayseraspis Harrington, 1938, or even as a junior synonym to the latter genus. Megalaspis (Paramegalaspis) immarginata Thoral, 1935, is designated as the type species of the genus Paramegalspis (nomen nudum in Thoral, 1935). A new genus Homalopyge n. gen. is erected with Asaphus stacyi Fr. Schmidt, 1898, as the type species.