Stegostriaria 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 : 463

Genus Stegostriaria Shear & Marek , new genus

Type species: Stegostriaria dulcidormus Shear & Marek , new species

Etymology: The name of the genus is a feminine Latin neologism based on the name of the dinosaur genus Stegosaurus Marsh, 1877 and the type genus of the Striariidae , Striaria . Species of Stegosaurus are unusual in having a double row of crest-like plates down the back; the enlarged second crests of Stegostriaria n. gen. recall this character.

Diagnosis: A genus of the subfamily Trisariinae , distinct from Trisaria Shear, 2020 in having the second metazonital crests on each side exaggerated and in the presence of intercalary crests between the median sulcus and the first crests ( Figs 2–4 ). The ninth legs of males ( Fig. 18 ) are elaborately modified, unlike those in any other striariids.

Description: See the description of the type and only species, below.

Distribution: Presently known only from Linn and Tillamook Counties, Oregon, USA.

Notes: The discovery of a second genus requires some modifications to the description of the subfamily Trisariinae . The suppression in Trisaria species of the fourth crests is not seen in Stegostriaria , where the third to sixth crests are subequal ( Figs 2, 3 ). Likewise, the gonopod colpocoxite in Stegostriaria n. gen. is not a poorly sclerotized posterior lobe but modified into a long, many-branched structure (cc, Figs 14, 15 , 17 ). While the ninth legs of males show a considerable degree of fusion, both the coxal and telopodite regions show elaborate modifications ( Fig. 18 )

Figures

FIGURES 1–6. Stegostriaria dulcidormus n. gen., n. sp., male paratype. 1. Head and leg 1, ventral view. 2. Midbody rings, lateral view. 3. Midbody rings, oblique dorsal view. 4. Rings 25–29 and telson, dorsal view. 5. Limbus, dorsal view. 6. Sculpture of telson, dorsal view.

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 12–15. Stegostriaria dulcidormus n. gen., n. sp., male paratype. 12. Tarsal setae of legpair 34, lateral view. 13. Gonopods, anterior view. 14. Gonopods, ventral view. 15. Gonopods, posterioventral view.