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 Retrorsia benedictae Shelley Figs 29–39 , 122 Retrorsia benedictae Shelley, 2003:7 Type locality. Along Oregon Rt. 202, 3 mi ( 4.8 km ) SE of Olney , Clatsop County , Oregon . FIGURES 29–31 . Retrorsia benedictae Shelley. 29 . Male, lateral view. 30 . Head and anterior rings, dorsal view. 31 . Pygidium, lateral view. SEM stub WS32-14. FIGURES 32–36 . Retrorsia benedictae Shelley. 32 . Midbody ring, dorsal view. 33 . Limbus. 34 . Accessory sensory area on sixth segment of antenna, lateral view. 35 . Gonopods in situ , posterior view. 36 . Left gonopod, lateral view. SEM stub WS32-14. Abbreviations: ac , acropodite; cx , coxa; p , pulvillus; pf , prefemorite; rn , rounded notch distal to pulvillus; rp , retrorse process; tz , terminal zone. Diagnosis. The semicircular notch in the gonopod is prominent ( rn, Fig. 36 ) but separated from the pulvillus ( p, Fig. 35 ) by half the length of the terminal zone (see also Fig. 121 ). There are 16 or 18 setae in the anterior marginal row of the collum ( Fig. 30 ). A detailed description is available in Shelley (2003) . Notes. The male specimen we used for SEM examination ( Figs 29–39 ) had some interesting commensals/parasites, including a fungal capilliconidia (amphoromorph) of the genus Basidiobolus ( Enghoff & Reboleira 2017 ) on an antenna ( Fig. 38 ) and the hypopis of an unidentified mite attached to the fifth ring ( Fig. 39 ). Distribution. Clatsop Co., Oregon ( Shelley 2003 ), and Pacific Co., Washington (new records below). FIGURES 37–39 . Retrorsia benedictae Shelley. 37 . Pulvillus of gonopod, posterior view. 38 . Suspected fungal theca on antenna. 39 . Hypopis of unidentified mite on fifth body ring. SEM stub 32-14. New records. WASHINGTON : Pacific Co . : 1.0 mi on Walberg Road , 0.4 mi west of Icwaco Water Park , 46.3236°, -123.9417°, 2 January 2005 , W. Leonard , C. Richart , m f; 1.1 mi south of SR6 on Trap Creek Road , Bline , 46.5432°-123.6152°, 19 November 2005 , W. Leonard , C. Richart , m; 2 mi west of Astoria Bridge on US 101, 10 ft asl, 46.2569 , -123.9250 °, 2 January 2005 , W. Leonard , C. Richart , mm ff; 3.5 mi south of Naselle on SR401 at Cement Creek , 46.3341°, -123.8003°, 15 January 2006 , W. Leonard , C. Richart , mm; 4.5 mi north of SR4 on US 101, at Middle Nemah River , 46.4874°, -123.8865°, 15 January 2006 , W. Leonard , C. Richart , mm ff; 5.9 mi south of SR6 on Trap Creek Road , Alder Creek drainage of Naselle River , 46.4973°, -123.6439°, 19 November 2005 , W. Leonard , C. Richart , m; east side of Ellsworth Creek , The Nature Conservency Preserve , 100 ft asl , 46.3838°, -123.8679°, 12 January 2004 , W. Leonard , mm ff; Long Beach , 30th St. , 0.2 mi from US 101, 50 ft asl, 46.3239°, -124.0598°, 15 January 2006 , W. Leonard , C. Richart , mm ff; Long Beach , Willows Road , 0.6 mi from 30th St. , 46.3229°, -124.0575°, 16 January 2006 , W. Leonard , C. Richart , mm ff; SR401 8 mi south of SR4, 40 ft asl, 46.2752°, -123.8158°, 2 January 2005 , W. Leonard , mm ff .