Taxonomic review of the genera Micridium Motschulsky, 1869 and Micridina Johnson, 1969 (Coleoptera: Ptiliidae) with eleven new species including the first records from South America and Madagascar Author Darby, Michael text Zootaxa 2017 4242 2 233 254 journal article 36307 10.11646/zootaxa.4242.2.2 c4e5d710-edf2-4928-b53d-22c211fcad53 1175-5326 376374 0DD1868D-4EF5-4FB7-AEE9-372644800A79 Micridium groehni Polilov & Perkovsky 2004 Described on the basis of a single specimen from Baltic amber ( Polilov & Perkovsky 2004 ). The photographs and line drawings included in the paper do not show the mesoventral carinae defining the genus Micridium as described here and the two depressions on the pronotum are rounded and not linear.