Three new genera and eighteen new species of miniature polydesmid millipedes from the northwestern United States (Diplopoda, Polydesmida, Polydesmidae) Author Shear, William A. Professor Emeritus, Department of Biology, Hampden-Sydney College, Hampden-Sydney VA 23943; present address 1950 Price Drive, Farmville VA 23901. Author Marek, Paul E. 0000-0002-7048-2514 Associate Professor, Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061. pmarek @ vt. edu; https: // orcid. org / 0000 - 0002 - 7048 - 2514 pmarek@vt.edu text Zootaxa 2021 2021-05-24 4975 1 81 126 journal article 6194 10.11646/zootaxa.4975.1.3 529d48db-4299-4e2d-9aaf-6c4178c08b18 1175-5326 4804909 DB7C9028-3EDF-454F-88D0-336624AD1DC4 Rowlandesmus Shear & Marek , new genus Type species : Rowlandesmus millicoma Shear & Marek , new species . Species included : Rowlandesmus millicoma n. sp. and R. dentogonopus , n. sp. Diagnosis. In their somatic characters, the two species of this genus are similar in nonsexual traits to the others described here, except that the metzonital tubercles carrying setae are generally lower and the surface of the metazonites of the midbody rings nearly smooth. The distinction lies in the gonopods Figs 88–90 , 93, 94 , 131, 132 ), in which the acropodite is sharply bent and reflexed in its distal third to half. Just distal or just proximal to this "kink" in the gonopod ( k, Fig. 88 ) is a short process. The pulvillus is basal to the “kink” and in R. millicoma , much expanded. Etymology. The genus is named for our late and much respected colleague, Rowland M. Shelley (1942–2018), one of the most productive millipede taxonomists of 20th and 21st centuries. He initiated the modern study of the small polydesmids of western North America with careful redescriptions of known genera and species and the description of Retrorsia Shelley, 2003 . Distribution. Douglas and Coos Cos., Oregon . Notes. We are placing both of these species in Rowlandesmus due to the similarity of the gonopods, with a sharp bend or “kink” in the acropodite causing the distal third to be reflexed at a right or lesser angle in relation to the basal part. Nevertheless there are some differences, and subsequent species discoveries may result in the two species being separated.