Chordeumatida, Striariidea, Striarioidea

Shear, William A., 2021, Additions to the millipede family Caseyidae. II. Martenseya, a new genus of miniature, blind millipedes from California (Diplopoda, Chordeumatida Striariidea, Striarioidea, Caseyidae), Zootaxa 4984 (1), pp. 108-113 : 109

Key to families of Chordeumatida in the Pacific Coastal States of the USA

1a. Head partially covered by collum........................................................................ 2

1b. Head not covered by collum............................................................................ 5

2a. Metazonites with strong longitudinal crests extending their full length; pygidium 3-lobed; southern California to British Columbia (also in Idaho and northern Virginia to northern Alabama)....................................... Striariidae

2b. Metazonites without long crests; pygidium not 3-lobed....................................................... 3

3a. Metazonites ornamented with scattered, closely set, short ridges; male ninth legs with 2 telopodite podomeres; northern California to Alaska (also in Idaho, Arizona, Utah, Illinois and Missouri).................................... Tingupidae

3b. Metazonite ornamentation granular, male ninth legs with a single telopodite podomere, or lacking telopodites........... 4

4a. Male ninth legs with a single, enlarged telopodite podomere; San Francisco Bay area to Alaska .......... Rhiscosomididae

4b. Male ninth legs much reduced, lacking telopodites, concealed by gonopods; southern California ............. Apterouridae

5a. Mature males with 26 postcephalic segments; northwestern Washington ........................ Anthroleucosomatidae

5b. Mature males with 28 or 30 postcephalic segments.......................................................... 6

6a. Mature males with 28 postcephalic segments; with ninth legs lacking telopodites, distinctly U-shaped, male tenth legs with enlarged coxosternum; western Washington .................................................... Microlympiidae

6b. Mature males with 28 or 30 (usually 30) postcephalic segments; ninth legs with prominent telopodites of one or two podomeres, tenth legs with coxae and sternum distinct................................................................. 7

7a. Metazonites with neither prominent projecting shoulders nor paranota, metazonital setae short; ninth leg telopodites of mature males with single enlarged podomeres; central California to Alaska ..................................... Caseyidae

7b. Metazonites with prominent projecting shoulders or paranota.................................................. 8

8a. Metazonites sparsely granular, with strong, flattened, rimmed paranota; metazonital setae short; pygidium with 3 lobes; ninth leg telopodites of males with single, swollen, button-like podomere; northwestern Washington ........ Urochordeumatidae

8b. Metazonites smooth, with prominently projecting shoulders sometimes paranota-like but never rimmed; metazonital setae long, curved; pygidium not lobed; ninth leg telopodites of males with two podomeres, the distal one cylindrical and turned dorsally; central California to Alaska (also Rocky Mountains from Alberta to Arizona, Mississippi Valley and Appalachian Mountains from New York to North Carolina).............................................................. Conotylidae