Expanded concept and revised taxonomy of the milliped family Xystodesmidae Cook, 1895 (Polydesmida: Leptodesmidea: Xystodesmoidea): incorporations of Euryuridae Pocock, 1909 and Eurymerodesmidae Causey, 1951, taxon revivals / proposals / transferrals, and a distributional update Author Shelley, Rowland M. Author Smith, Jamie M. text Insecta Mundi 2018 2018-09-28 660 1 41 journal article 10.5281/zenodo.3709976 b412f1c4-28b9-4786-9aec-f930c9c00373 1942-1354 3709976 015EC5C3-65C6-4418-BC6D-C36D58C4DCDD Subtribe Nannariina Hoffman 1964 , New Status Diagnosis. Flexible and pliable Eurymerodesmini; mandibular stipes smooth, without ridges or projec- tions; postgonopodal sterna of males and all sterna of females essentially glabrous, caudal margins with acuminate, subtriangular spines subtending leg coxae; ambulatory prefemora with ventrodistal spines; pregonopodal tarsal claws of males twisted, broad, and spatulate. Gonopodal aperture glabrous, rounded or ovoid, margins not modified. Gonopods in situ medially oriented, cannulae mediad and telopodites extending anteriad over anterior margins of apertures; telopodites usually with variable prefemoral processes, acropodital hairs moderately long, usually discontinuous with light apical tufts on “inner” margins not obscuring “distal zones.” Cyphopodal valves of normal sizes and proportions for family, completely hidden in apertures, distal corners without extensions and projections. Components. Nannaria and Mimuloria , both by Chamberlin; Oenomaea Hoffman ( Hoffman 1964a , 1980 , 1999 ; Hennen and Shelley 2015 ). Distribution ( Fig. 1 , green; Fig. 16 , red). East-Nearctic; endemic to the central and eastcentral US . The distribution extends, north/south, from Lake Ontario New York , northern Ohio , central Illinois , and Missouri south of the Missouri River to northeastern/eastcentral North Carolina , northernmost South Carolina , northern Georgia and Alabama, and northeastern Arkansas; east/west, it ranges from Virginia and Maryland west of Chesapeake Bay, eastcentral Pennsylvania, and adjacent New York to western Missouri and adjacent northern Arkansas. Remarks. Because of their clearly shared ancestry, we transfer this taxon from Xystodesminae to Eurymerodesmini, which holds priority by 13 years for the tribal name. Nannariinan acropodital hairs are longer than in any xystodesmine taxon, and they extend (dis)continuously along primarily the “inner” surface rather than the “outer,” as shown by Chamberlin (1949 , Fig 1 ) and Hoffman (1964a , Fig. 11 ) in the in situ gonopods of Nannaria minor Chamberlin. Additionally , eurymerodesminans and nannariinans are similar in overall body sizes and convexities of the dorsums. Divergence entailed development of a prefemoral process by Nannariina, which retained plain, ovoid apertures and traditional cyphopods, while Eurymerodesmina developed extreme elaborations of both, and their overlapping ranges in Arkansas and Missouri , west of the Mississippi River, and Illinois , Kentucky and Tennessee to the east, support our shared ancestry hypothesis. Molecular investigations are also in order.