Taxonomy of the Cape Verde endemic weevil genus Dinas (Coleoptera: Curculionidae: Entiminae). Part I: Description of a new subgenus, and two new species from Sao Nicolau Island

An extensive material of the Cape Verde endemic weevil genus Dinas Wollaston, 1867 (Curculionidae: Entiminae) is revised. Two subgenera are recognized based on the external morphology and biology of adults. Microspina subgen. nov. is established for the group with smaller-sized adults which are flower-eaters adapted to habitats with Macaronesian endemic flora; 10 species are transferred to the subgenus: D. (M) angusticeps Roudier, 1957, D. (M) angustula Wollaston, 1867, D. (M) elliptipennis Wollaston, 1867, D. (M) heckeli Geisthardt, 1995, D. (M) micans Roudier, 1957, D. (M) obsita Wollaston, 1867, D. (M) pallipes Roudier, 1957, D. (M) punctipennis Roudier, 1957, D. (M) sitonaeformis Wollaston, 1867, and D. (M) viridisquamea Roudier, 1957. Contrary, adults of Dinas s. str. were found on the ground and under stones only. The Dinas fauna of Sao Nicolau Island is studied in detail. Dinas (Microspina) afonsoi sp. nov. and D. (Dinas) strakai sp. nov. are described from the eastern part of the island. The types and new material of the remaining two species from the western part of the island, D. (Microspina) angusticeps and D. (Microspina) sitonaeformis, are reviewed, and lectotype for the latter is designated. An identification key to all species known from Sao Nicolau is provided. The origin of Dinas and its biogeographic affinities are discussed. Distributional pattern of the genus within the archipelago, particularly in Sao Nicolau are commented. An updated list of all known Dinas species is provided.