The milliped family Nearctodesmidae in northwestern North America, with accounts of Sakophallus and S. simplex Chamberlin (Polydesmida)

Abstract

In northwestern North America, the milliped family Nearctodesmidae is comprised of four genera, Nearctodesmus Silvestri, Kepolydesmus Chamberlin, Ergodesmus Chamberlin, and Bistolodesmus, new genus, and six species, N. insulans (Chamberlin), N. cerasinus (Wood), N. salix Chamberlin, K. anderisus Chamberlin, E. compactus Chamberlin, and B. bonikus (Chamberlin). These species occur along the Pacific coast from San Francisco Bay to Prince Rupert, British Columbia, including all offshore island groups, with an eastward extension into Lewis and Clark County, Montana, east of the Continental Divide. An allopatric population of N. insulanus occurs in the Shuswap Highlands of British Columbia, and an allopatric species, E. remingtoni (Hoffman), inhabits caves in western and southern Illinois. The principal taxonomic characters are the number of secondary projections from the gonopodal telopodite, the configuration of the longer of these, and the length and configuration of the distal zone of the acropodite. Polydesmus bonikus is a nearctodesmid and is assigned to the new genus, Bistolodesmus. The following new synonymies are proposed: Jaliscodesmus Hoffman under Sakophallus Chamberlin; J. alticola Hoffman under S. simplex Chamberlin; N. brunnior, N. campicolens, and N. malkini, all by Chamberlin, under N. cerasinus; N. amissus, N. pseustes, N. renigens, N. carli, and N. boydi, all by Chamberlin, and N. olympus and N. cochlearius, both by Causey, under N. insulanus; K. mimus, K. hesperus, and K. pungo, all by Chamberlin, under K. anderisus; and Ectopodesmus cristatus and E. c. dentatus, both by Loomis and Schmitt, under Ergodesmus compactus. Modern diagnoses and illustrations are presented for the family and all northwestern taxa, along with keys to the genera and species of Nearctodesmus. Accounts and gonopod drawings are also presented of Sakophallus and S. simplex Chamberlin in Michoacan and Jalisco, Mexico.

The milliped genus Tidesmus Chamberlin, 1943 (Polydesmida: Macrosternodesmidae)

“…In placing Tidesmus under "Trichopolydesmoidea of uncertain family position," Hoffman (1980) indicated that he did not consider it a polydesmoid, but he could not decide among the three New World trichopolydesmoid taxa (sensu Shelley (2003a), which are difficult to distinguish: Macrosternodesmidae, Nearctodesmidae, and Fuhrmannodesmidae (= Vanhoeffeniidae). Of these taxa, only Nearctodesmidae has been revised (Shelley 1994) and rediagnosed (Shelley & Shear 2006); Fuhrmannodesmidae, a "dumping ground" for small Neotropical trichopolydesmideans, is not known north of Mexico and is irrelevant to our considerations even though Golovatch (1994) thought three southwestern US genera-Harpogonopus, Oodedesmus, and Phreatodesmus, all by Loomis (1960)-belong here. Harpogonopus, often misspelled as "Harpagonopus," really belongs to the Nearctodesmidae (Shelley 1994), and our research shows that Oodedesmus and Phreatodesmus are representatives of the Macrosternodesmidae and, moreover, synonyms of Tidesmus.…”

“…The southwestern United States (US) and northwestern Mexico harbor a surprising diversity of diplopods in, primarily, three families-Spirostreptidae (Spirostreptida), Atopetholidae (Spirobolida), and Schizopetalidae (Callipodida)-all of which have received initial alpha-taxonomic treatments (Hoffman & Orcutt 1960, Causey 1975, Shelley 1996a. Herein and in planned future contributions, we address a fourth component of the North American desert milliped fauna, the minute representatives of the order Polydesmida that have been labeled "micro-nearctodesmids" (Shelley 1994, Shelley & Shear 2006 and formally placed in the families Polydesmidae (Chamberlin 1943, Chamberlin & Hoffman 1958, Vanhoeffeniidae (Loomis 1960), Fuhrmannodesmidae (Hoffman 1999;Golovatch 1994), and "Trichopolydesmoidea of uncertain family position" (Hoffman 1980). They are active primarily in cooler seasons of the year in summit forests on inselberg mountains or in close proximity to springs and other water sources.…”

A reclassification of the millipede superfamily Trichopolydesmoidea, with descriptions of two new species from the Aegean region (Diplopoda, Polydesmida)

“…Shelley (1994) gave a detailed morphological description of nearctodesmids and revived their family status, contrary to Hoffman (1982) who had synonymized the Nearctodesmidae with Macrosternodesmidae. Later, however, apparently following Shelley (1994), Hoffman (1999) also considered the Nearctodesmidae as a distinct family.…”

“…Later, however, apparently following Shelley (1994), Hoffman (1999) also considered the Nearctodesmidae as a distinct family.…”

“…The diversity of gonopod structural plans in nearctodesmids+macrosternodesmids (Shelley 1994, Shear and Shelley 2007) appears to be quite modest and uniform, since all of their constituent genera such as Nearctodesmus Silvestri, 1910, Kepolydesmus Chamberlin, 1910, Bistolodesmus Shelley, 1994, Tidesmus Chamberlin, 1943 etc. show clearly transverse and elongated prefemoral portions which are set subrectangular to the subparallel, usually bi- or triramous, elaborate, normally clearly curved and well exposed acropodites.…”