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 Tribe Eurymerodesmini Causey 1951 , New Status Diagnosis. Small to moderately long and broad, stiff and inflexible or flexible Euryurinae with apically narrow, subtriangular epiprocts, anteriolateral paranotal corners smoothly rounded, without teeth; postgonopodal sterna in males and all sterna in females nearly glabrous or variably hirsute; ambulatory prefemora with or without spines. Gonopodal aperture glabrous and rounded/ovoid or large, hirsute, and elaborately modified with anterior indentations, and triangular or clavate lobes on caudal margins or flared caudolateral corners. Gonopodal coxae connected by membrane only, without sclerotized sterna or remnant of same; telopodites with or without variably long prefemoral processes and partial prefemoral extensions; plesiomorphic acropodites long, slender, and “stick-like,” extending sublinearly from prefemur and curving/bending abruptly (90°) subapically, “distal zones” short, apically (sub)acuminate; “inner” surfaces of acropodital stems adorned (dis)continuously up to “distal bends” with moderately long to long, stiff or wavy and flexible hairs, with or without apical clusters/tufts and equivalent tufts on “outer” margins. Cyphopod valves normal for family or enlarged with modified, dactyliform distal corners. Components. Two subtribes, Eurymerodesmina and Nannariina, new statuses . Distribution. East-Nearctic/eastern, central, southcentral, and southeastern US . The combined ranges of the two components encompass much of the eastern 1/2–2/3 of the US and extend, north/south, from western New York , northern Ohio and Indiana , central Illinois , Missouri south of the Missouri River, and northeastern Nebraska to northern peninsular Florida , the Gulf Coasts of Florida through Texas , and the Rio Grande. East/west, Eurymerodesmini extends from westcentral New York , eastcentral Pennsylvania , Maryland and Virginia west of Chesapeake Bay, and the Atlantic Coast of southeastern North Carolina through northeastern Florida to northeastern Nebraska and central Kansas , then angling progressively southwestward to the Rio Grande in Texas west of the confluence with the Pecos River ( Fig. 1 , 7 ). A curious, slit-like hiatus curves from eastern North Carolina through central South Carolina and northcentral Georgia to northern Alabama. RMS has sampled intensively in this lacuna from North Carolina to Georgia without encountering either component, so students should be alert to potentially filling it in the future.