Bifurcatella pacifica, Shear & Richart & Wong, 2020

Shear, William A., Richart, Casey H. & Wong, Victoria L., 2020, The millipede family Conotylidae in northwestern North America, with a complete bibliography of the family (Diplopoda, Chordeumatida, Heterochordeumatidea, Conotyloidea), Zootaxa 4753 (1), pp. 1-78 : 58-59

Bifurcatella pacifica , new species

Figs. 218, 219 , 222, 223

Types: Male holotype and male and female paratypes from WASHINGTON: Pacific Co., Ellsworth Creek Preserve , elev. 50 m., 46.3981°N, - 123.8898°W, collected 23 November 2003 by W. Leonard et al. in old growth forest .

Diagnosis: Like the following species, B. pacifica has the pseudoflagellar branch of the posterior gonopod coxite tightly doubled on itself, and the fimbriate branch is large. However, the anterior gonopods are quite different; in B. pacifica the lateral branch has a distinct shoulder distal of which the branch narrows to a simple tip, while in B. germania n. sp. (see below) the anterior gonopod lateral branch tapers more or less evenly and has three triangular teeth subtending the tip.

Etymology: The species is named for Pacific County, Washington.

Description: Male holotype: Length, 10.00 mm. Eighteen to 20 ocelli in triangular group. Metazonites with well-developed shoulders, segmental setae curved, acute. Color pale tan to chestnut, marked purplish brown on metazonites and prozonites such that dorsally two parallel rows of dark spots appear, additional rows on both lateral surfaces of rings. Legpairs one and two reduced, three through seven enlarged, fourth pair with low femoral knobs, fifth pair with large, acute, distal femoral knobs. Anterior gonopods ( Figs. 218 , 222 ) with mesal branches, blunt, cylindrical, approximately one-third length of lateral branches; lateral branches thickest at midlength with distinct constriction distal to posterior shelf, distal part curved, acute at tip, with subdistal ridged region. Posterior gonopod coxites ( Figs. 219 , 223 ) with main branch narrow, ending bluntly, two strong fimbriate branches embrace tightly folded, rapidly tapering pseudoflagellar branch. Tenth coxae conspicuously enlarged, glandular; eleventh prefemora with usual process.

Female 10.00 mm long, nonsexual characters as in male.

Distribution: WASHINGTON: Pacific Co., Walberg Road 1.0 mi N of Chinook Valley Rd, or 0.4 mi W of Ilwaco Water Park, elev. 30 m., 46.3235°N, - 123.9417°W, 2 January 2005, W. Leonard, C. Richart, from the litter and woody debris of a mixed forest including Alnus rubra , Tsuga heterophylla , Polystichum munitum , and Rubus spectabilus , mm.

Figures

FIGS. 218–221. Bifurcatella spp. Figs. 217, 218. Bifurcatella pacifica. Fig. 218. Anterior gonopods, posteriolateral view. Fig. 219. Left posterior gonopod coxite, posterior view. Figs. 220, 221. Bifurcatella germania. Fig. 220.Anterior gonopods, posterior view. Fig. 221. Right posterior gonopod coxite, posterior view.

FIGS. 222–227. Bifurcatella spp. Figs. 222, 223. Bifurcatella pacifica. Fig. 222. Right anterior gonopod, posterior view. Fig. 223. Left posterior gonopod coxite, posterior view. Figs. 224, 225. Bifurcatella germania. Fig. 224. Right anterior gonopod, posterior view. Fig. 225. Left posterior gonopod coxite, posterior view. Figs. 226, 227. Bifurcatella uniclada. Fig. 226. Right anterior gonopod, posterior view. Fig. 227. Left posterior gonopod coxite, posterior view.