Kentrostriaria ohara Shear & Marek, 2022

Shear, William A. & Marek, Paul E., 2022, The milliped family Striariidae Bollman, 1893. V. Stegostriaria dulcidormus, n. gen., n. sp., Kentrostriaria ohara, n. gen., n. sp., and the convergent evolution of exaggerated metazonital crests (Diplopoda, Chordeumatida, Striarioidea), Zootaxa 5094 (3), pp. 461-472 : 467-469

Kentrostriaria ohara Shear & Marek , new species

Figs 19–26

Types: Male holotype and female paratype from the O’Hara Bar Campground on the Selway River, Nez Percé National Forest, Idaho Co., Idaho, USA, 46.08521°N, - 115. 51761°W, 1600’ asl, collected 14 October 2006 by C. Richart, W. Leonard and A. Fusek. The male holotype and female paratype are mounted on SEM stub WS36-18. An additional female paratype is from the same locality, but collected 2 April 2003 by W. Leonard, J. Bough and J. Degenhardt. All types including SEM stubs deposited in the California Academy of Sciences , San Francisco, California, USA .

Etymology: The species epithet is a noun in apposition, after the type locality.

Diagnosis: See the diagnosis of the genus, above. This is the only known species.

Description: Male holotype. Length, ca. 4.5–5.0 mm, width ca. 0.4–0.5 mm. Twenty-nine thoracic rings, including telson.

Head densely setose, with minimal pebbled sculpture. Antennae as usual for family. Two black ommatidia on either side of head. Labrum without lateral processes. Mandibular stipes with slight serrate distal edge, lacking acute posteriodistal corner.

Collum with distinct pebbled sculpture throughout, crests low, inconspicuous, restricted to posterior half; collum with distinct anteriolateral notches on each side, from which originate lateralmost segmental setae ( Fig. 24 ). Collum with long, acute segmental setae, but such setae not detectable on more posterior trunk rings. Rings 2 and 3 with subequal but prominent crests. Rings 4–6 with both second and third crests exaggerated; second crests the highest, divergent ( Fig. 25 ). From ring 7 posterior, third crest returns to normal size while sixth crest becomes slightly larger ( Figs 26, 27 ).

Telson with lobes not separated by deep incisions, without crests ( Figs 25, 26 ).

First, second and third legpairs subequal in size, first legpair with long setae, third coxae with moderately developed coxal flasks. Second leg prefemor (tr2, Fig. 19 ) with prominent setose process (ptr, Fig. 19 ), coxa with vas deferens opening at tip of short process, membranous but with small, scale-like setae ( Fig. 20 ). Fourth to seventh legpairs encrassate. Seventh legpair without coxal lobes.

Gonopods ( Figs 21, 22 ) very small. Sternum (s, Figs 21, 22 ) prominent, with deep medial embayment. Coxae (cx, Fig. 21 ) with array of about 6 stout setae. Anterior angiocoxite (aac, Figs 21, 22 ) not divided, tipped with array of fine cuticular projections. Posterior angiocoxite reduced, sheathing at least two flagellocoxites (fc, Fig. 21 ). Colpocoxite apparently reduced, posterior part with fimbriate branches (cc?, Fig. 22 ). Ninth legs with all elements free, telopodite (t9, Fig. 23 ) flattened, heavily pebbled.

Female paratype. Similar to male, but second crests much lower on posterior segments than in male ( Fig. 28 ).

Figures

FIGURES 16–23. New species of striariid millipeds. Figs 16–18. Stegostriaria dulcidormus n. gen., n. sp., male paratype. 16. Right gonopod, lateral view, anterior to the left. 17. Left gonopod, mesal view, anterior to the left. 18. Legpair 9, anterior view. Figs 19–23. Kentrostriaria ohara n. gen., n. sp., male holotype. 19. Left leg 2, posterior view. 20. Gonophore, anterior view. 21. Right gonopod, anterior view. 22. Left gonopod, anteriomesal view.

FIGURES 24–29. Striariid millipedes. Figs 24–27. Kentrostriaria ohara n. gen., n. sp. male holotype. 24. Head, collum and rings 2–4, oblique view. 25. Rings 3–5, dorsal view. 26. Rings 12–14, dorsal view. 27. Rings 22–28 and telson, oblique view. 28. Kentrostriaria ohara n. gen., n. sp. female paratype, rings 22–28 and telson, lateral view. 29. Midbody segment of undescribed Striaria species from Waterrock Knob, North Carolina, dorsal view.