Bifurcatella uniclada, 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 : 60

Bifurcatella uniclada , new species

Figs. 226–229

Types: Male holotype and male and female paratypes from WASHINGTON: Lewis Co., Slide Creek , Weyerhaeuser 4000 Road 0.8 mi SW of Pe-Ell-McDonald Road , elev. 200 m, 46.5241°N, - 123.1934°W, collected 3 January 2005, by W. Leonard .

Diagnosis: Similar to the foregoing two species but distinct in that the anterior gonopods lack mesal branches and terminate in a series of finger-like projections from a flattened, palm-like tip. Also, the posterior gonopod coxite pseudoflagellar branch is greatly thickened about midway in its length and then tapers rapidly to a very thin tip.

Etymology: The species epithet, an adjective, refers to the lack of a mesal branch on the anterior gonopod.

Description: Male holotype: Length, 12.0 mm. Twenty to 22 ocelli in triangular group.

Segmental shoulders well-developed, setae long, curved, acute. Color mostly dark purplish brown in continuous bands across metazonites but with conspicuous white to pale tan spots on shoulders. Legpairs one and two reduced, pairs three to seven encrassate, femoral knobs on pairs four and five. Anterior gonopods ( Figs. 226 , 228 ) long, thin, curved at tip, with three to five finger-like projections. Posterior gonopod coxites ( Figs. 227 , 229 ) robust, broad-tipped, with large basal flange that presses against projection from gonopod prefemur; pseudoflagellar branch strongly sinuate, greatly thickened midlength, abruptly tapering, conspicuously fimbriate near tip; fimbriate branches not as large as in preceding two species. Gonopod femur narrow. Tenth coxae and eleventh prefemora as usual.

Female 11.00 mm long, nonsexual characters as in male.

Distribution: WASHINGTON: Pacific Co., Trap Creek Road 5.9 mi S of SR-6, Alder Creek drainage of Naselle River, elev. 230 m., 46.4972°N, - 123.6439°W, 19 November 2005, W. Leonard, C. Richart, m; Cement Creek, SR-401 2.5 mi S of Parpala Road in Naselle, elev. 30 m., 46.3341°N, - 123.8002°W, 15 January 2006, W. Leonard, C. Richart, from the litter of a riparian forest including Alnus rubra , Picea sitchensis , Sambucus cf. caerulea , and Polystichum munitum , m; 3 horiz mi S, 2 horiz mi W of Menlo, estimated coordinates and elevation taken from headwater stream adjacent Ehmer Road, elev. ca. 255 m., 46.5769°N, - 123.6892°W, 20 December 2003, W. Leonard et al., m f. Lewis Co., in Lewis County only known from the type locality.

Notes: Despite lacking mesal branches on the anterior gonopods, the posterior gonopod coxites clearly mark this species as a Bifurcatella . The basal, posterior flanges and the basal projection from the posterior gonopod prefemur are also distinctive.

Figures

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.

FIGS. 228–231. Bifurcatella spp. Figs. 228, 229. Bifurcatella uniclada. Fig. 228. Right anterior gonopod, posterior view. Fig. 229. Right posterior gonopod coxite, posterior view. Figs. 230, 231. Bifurcatella inflata. Fig. 230. Left anterior gonopod, posterior view. Fig. 231. Right posterior gonopod coxite, posterior view.