Euryuridae, Pocock, 1909

Shelley, Rowland M. & Smith, Jamie M., 2018, 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, Insecta Mundi 660, pp. 1-41 : 6

Euryuridae , Melaphini, and Devilleini.

The family-group taxon based on Euryurus has been repeatedly reconceptualized, and its tangled history is summarized by Hoffman (1954, 1998a) and Jorgensen (2009). Most recently, Hoffman (1998a, 1999) considered it a full family with close affinity to the Mediterranean xystodesmid tribe Melaphini because of somatic and gonopodal similarities between Euryurus and Melaphe . Obviously, Euryurus and Melaphe , and hence Euryuridae and Melaphinae , are related. Their paranota possess marginal anteriolateral teeth, and their gonopodal acropodites curve/bend around midlengths and possess complete “prefemoral elongations” that extend for equivalent distances with similar pilosities along their “inner” surfaces ( Fig. 2–7 ). Indeed, the gonopodal configurations of M. corrupta Attems , E. maculatus (Koch) , and E. l. leachii (Gray) ( Fig. 2–5 ) are closely similar as are those of M. vestita (Koch) and E. mississippiensis (Causey) ( Fig. 6–7 ). Thus, since Euryuridae is closely related to Melaphini , a xystodesmid component, it must also be such or together they comprise a separate family. The evolutionary hypothesis of Shelley and Golovatch (2011) provides a basis for interpreting how confamilial statuses developed and a reasonable explanation for the evolution of Euryurus , Melaphe , and traditional Xystodesminae from common ancestral stock (see Evolution section). Confirmation or disproval with molecular data is desirable, but this is beyond our present scope.

Relevant illustrations of Melaphe spp. showing long hairs extending distad along the inner surfaces of the prefemoral elongations and acropodites are available in Hoffman (1962a, 1998a) and Hoffman and Lohmander (1968). Published illustrations of Devillea spp. gonopods ( Brölemann 1902, 1916; Verhoeff 1931; Attems 1938, 1940; Strasser 1960) differ from those of Melaphe and Ochridaphe in possessing looped acropodites, “prefemoral processes,” and acropodital hairs on the “outer” surfaces. Hoffman (1980) accepted Devillea in the monotypic tribe Devilleini (Xystodesminae) and Marek et al (2014) reiterated this assignment. Melaphe and Ochridaphe are properly contribal, as they share gently curved acropodites, “prefemoral extensions,” “distal zones,” and moderately long hairs along the “inner” surfaces of the extensions and acropodites to near the “distal bends.” This positional marker is sharp and subapical in Devillea , the distal zone is bifurcate, and short, scattered hairs extend about halfway along the “outer” acropodital surfaces ( Brölemann 1902; Attems 1938; Strasser 1960, 1974a). Both Devillea and Melaphe have highly disparate distributions ( Fig. 17 , 21 ) that seem somewhat relictual, and both logically derive from xystodesmoidean radiations onto Baltica after it merged with the Avalonia terrane in the early Silurian Paleogeological Period, some 450 million years ago (mya) ( Shelley and Golovatch 2011).

Figures

Figure 17. Global distribution of Xystodesmidae.

Figure 21. Distribution of the polydesmidan suborder Leptodesmidea in the Mediterranean Region of Europe, Africa, and Middle Eastern Asia. Black lines and dots, West-Palearctic Region of Xystodesmidae. Red line, area of Spain/Iberian Peninsula occupied by Macellolophus excavatus (Chelodesmidae). Red stars, localities in the same of Cantabrodesmus lorioli (Chelodesmidae). Green triangles, denoted by green arrow in eastern Mediterranean Sea, localities of Libanaphe spp. (Oxydesmidae) in Lebanon and Israel.

Figures 2–7. Euryurini gonopodal telopodites; 2–4 and 7, Euryurina, 5–6, Melaphina. 2) Euryurus carolinensis (Saussure), Orange Co., NC. 3) E. l. leachi (Gray), Hamilton Co., OH. 4) E. maculatus Koch, Wilkinson Co., GA. 5) Melaphe corrupta Attems, locality unknown. 6) M. vestita (Koch), locality unknown. 7) E. mississippiensis (Causey), Jackson Co., MS. Figures 2–4 reprinted from Hoffman (1978b) with permission from the American Entomological Society. Figure 5 reprinted from Hoffman (1962a) with permission from the Bavarian State Collection of Zoology, Munich. Figure 6 reprinted from Hoffman (1998a) with permission from the Virginia Museum of Natural History. Figure 7 adapted from Causey (1955a) with permission from the Biological Society of Washington.