The millipede family Striariidae Bollman, 1893. II. New records and species of the genus Amplaria Chamberlin, 1941 (Diplopoda, Chordeumatida, Striarioidea) Author Shear, William A. Professor Emeritus, Department of Biology, Hampden-Sydney College, Hampden-Sydney VA 23943 USA; current address: 1950 Price Drive, Farmville VA 23901 USA. text Zootaxa 2021 2021-01-14 4908 2 205 224 journal article 8837 10.11646/zootaxa.4908.2.3 65624457-9eba-46fa-93dc-dfadc60cb618 1175-5326 4438304 BEE08FC0-68C2-469D-BDEA-4F1D9843012E Amplaria arcata , n. sp. Figs. 15–26 Types : Male holotype and male paratype from Prairie Creek Redwoods State Park , 41.3729833°, 124.0138833°, 252’ asl, Humboldt Co. , California , collected 21 December 2006 by C. H. Richart , A. Fusek (Richart collection number CHR 1041). Parts of these specimens are mounted on SEM stubs: WAS33-18, WAS34-1, WAS34-2 and WAS34-3 . Diagnosis : Distinct from A. rykkenae , the other species in the group, in having the femora of the second pair of legs of the males much enlarged, nearly as wide as long ( Fig. 15 ). Etymology : The species name is a noun in apposition and refers to the nearby town of Arcata, where the species was also collected FIGS. 11–13. Amplaria rykkenae . Fig. 11. Gonopods, anterior view. Fig. 12. Gonopod tips, anterior view. Fig. 13. Legpair 9, anterior view. Description : Male paratype . Length about 10.5 mm , width about 1.0 mm. Seven or eight black ommatidia in triangular patch. Labrum with long, sinuate hooks; mandible not modified ( Fig. 15 ). Legpairs 1 and 2 subequal, legs 1 without long setae, tarsi ventrally with twisted, spatulate setae ( Figs. 15–17 ). Trochanters of second legs with short ventral process with patch of specialized setae, femora enlarged, oval, inflated. Coxal flasks of third legs ( Figs. 18 , 21 ) evenly curved, tapering, pleurotergal bars of third ring narrow, not meeting in midline ( Fig. 18 ). Legpairs 4–7 enlarged, with flattened podomeres, coxae unmodified except for lobes on coxae 7. Metazonital crests prominent, more so posteriorly, posterior part of crests raised on rings 21–27 ( Fig. 20 ). Pygidium elongate ( Fig. 19 , 20 ), divisions between lobes deep, narrow. Color medium tan, crests darker, posterior edge of each crest outlined in purplish brown. Gonopods ( Figs. 25, 26 ) similar to those of A. rykkeni , but with fewer spiculate processes on posteriodistal part of anterior angiocoxites, which bear large, blunt lateral lobes. Ninth legs ( Fig. 24 ) also similar to those of A. rykkeni , articulating loosely with depressions in pleurotergal margins of ring 7. Female similar to males in nonsexual characters. Distribution : In addition to type locality known from CALIFORNIA : Humboldt Co.: Arcata, Community Forest east of Humboldt State University, 40.8699°, -124.0725°, collected 31 March 2011 by C. H. Richart et al. mmff.