Ochrogramma skamania Shear and Marek, 2024

Ochrogramma skamania Shear and Marek , new species

( Fig. 38–47 View Figures 38–41 View Figures 42–45 View Figures 46–49 )

Types. Male holotype (VMNH11244), five male paratypes (VMNH11245.1–5) and 11 female paratypes (VMNH11246.1–11) from Spring Creek Hatchery on State Route 14, 45°43.680′, −121°32.672′, 50′ asl, Skamania Co., Washington, collected 30 November 2003 by W. Leonard, deposited in VMNH.

Etymology. This species has been collected only in Skamania Co., Washington, and the species epithet is a noun in apposition after the name of the county.

Diagnosis. Ochrogramma skamania , new species, is distinct from the other species of the genus in that the anterior angiocoxite (aac, Fig. 40 View Figures 38–41 ) of the gonopod is not twisted, while arborescent processes are present on the anterior surface ( Fig. 41 View Figures 38–41 , 45 View Figures 42–45 ); the ninth leg coxal processes are not divided as in the other species but instead are entire and squared off distally (cp, Fig. 46 View Figures 46–49 ).

Description. Male paratype from Spring Creek Hatchery. Length, ca. 10 mm, width 0.85 mm. Eyepatch of 17–19 ommatidia. Mandibular stipes with strongly developed distal lobe. Thirty rings. Rings cylindrical, smooth dorsally, laterally with 10-12 prominent horizontal striations. Segmental setae acute, short. Color purplish to brownish gray, with yellow-tan spots around sockets of segmental setae and dorsal yellow-tan stripe more prominent posteriorly. Sides of rings yellowish with striations darker purplish gray. First legpair ( Fig. 38 View Figures 38–41 ) short, arising from a coxosternum (cxs1, Fig. 38 View Figures 38–41 ), postfemora, tibiae and tarsi with long, flattened, spirally curved setae. Second legpair ( Fig. 39 View Figures 38–41 ) with coxal gonapophyses (ga, Fig. 39 View Figures 38–41 ) longer than telopodites (pf2 et seq., Fig. 39 View Figures 38–41 ). Third legpair ( Fig. 39 View Figures 38–41 ) with coxae (cx3, Fig. 39 View Figures 38–41 ) not fused with sternum (s3, Fig. 39 View Figures 38–41 ), elongated into rounded lobes (cl, Fig. 39 View Figures 38–41 ), distally with specialized setae as in O. haigi ( Fig. 35 View Figures 32–37 ); telopodites (t3, Fig. 39 View Figures 38–41 ) articulating about two-thirds distal on coxae. Seventh legpair with short coxal lobes. Gonopods ( Fig. 40–45 View Figures 38–41 View Figures 42–45 , 49 View Figures 46–49 ) with coxae and sternum (s, Fig. 40, 41 View Figures 38–41 ) clearly separate, coxae (c, Fig. 40, 41 View Figures 38–41 ) rounded, cupulate. Anterior angiocoxites (aac, Fig. 40–45 View Figures 38–41 View Figures 42–45 ) slender, curved, slightly expanded and rugose at tips, with arborescent processes on anterior distal surface. Flagellocoxites (f, Fig. 42, 43 View Figures 42–45 ) three, long, branched, almost feathery, appressed to posterior surface of anterior angiocoxite. Telopodites absent. Posterior angiocoxite (pac, Fig. 42–44 View Figures 42–45 ) rodlike, apically divided into several fine filaments. Colpocoxites (cc, Fig. 40–43 View Figures 38–41 View Figures 42–45 ) weakly sclerotized, arising from coxal sockets, directed mesally. Ninth legpair ( Fig. 46 View Figures 46–49 ) with coxae (cx9, Fig. 46 View Figures 46–49 ) free from sternum, each bearing long, unbranched mesal process (cp, Fig. 46 View Figures 46–49 ), curved and truncate at tip; prominent pore (p, Fig. 46 View Figures 46–49 ) at anterior base of each coxal process. Tenth legpair coxae (cx10, Fig. 48 View Figures 46–49 ) much enlarged, with large, anterior gland openings (cxg, Fig. 48 View Figures 46–49 ); trochanters (tr10, Fig. 48 View Figures 46–49 ) partly fused to coxae, distally with bifid, blunt process bearing many small teeth (trp, Fig. 48 View Figures 46–49 ).

Female paratype from Spring Creek Hatchery. Length, ca. 15 mm, width 1.2 mm. Nonsexual characters as in male, but dorsal yellow stripe more prominent, extending further anterior. Female genitalia ( Fig. 47 View Figures 46–49 ) with widely separated outer (ov) and inner (iv) lobes, outer lobes shorter, both lobes with strong distal processes. Receptacles not observed, postgenital plate absent.

Records

WASHINGTON: Skamania Co.: Cape Horn , 45°34.29′, −122°11.86′, 400′ asl, 19 November 2004, W. Leonard, m, ff ( VMNH) ; Cook-Underwood Road, 1.4 mi northeast of Cook , 45°434′, −121°38.859′, 450′ asl, 30 November 2003, W. Leonard, f ( VMNH) .

Note. This is the first new species of Ochrogramma from north of the Columbia River.

Spermatophores and Spermatozoa

Millipede spermatocytes and spermatozoa were reviewed by Minelli and Michalik (2015), among others. Millipede spermatozoa are highly variable in form from order to order, but all are evidently nonmotile. According to Minelli and Michalik (2015), no anatomical or ultrastructural studies have been carried out on any nematophoran taxa, so our observations here, however sketchy, are the first data on spermatozoa of this large taxon which includes the orders Callipodida and Chordeumatida . Our SEM pictures only show spermatozoa embedded in a matrix, evidently comprising a spermatophore ( Fig. 28 View Figures 25–28 ). They appear to be subglobular or slightly flattened (most closely resembling the spermatozoa of the order Julida , based on the illustrations in Bacetti et al. [1979]) and 14–14.5 µm in diameter. There is no indication of any organ of motility.

Minelli and Michalik (2015) make no reference to spermatophores, nor do they in a discussion of mating behavior immediately following. This is curious, as the paper by Mathews and Bultman (1993) clearly discusses a spermatophore in the mating of the parajulid ( Julida ) Aniulus bollmani Causey, 1952 (= Aniulus garius (Chamberlin, 1912) . This is not the place for a review of either the evidence for, or speculation about, spermatophores in chordeumatidan millipedes, aside from positing the idea that sperm from the vas deferens, opening on the second coxae, are first transferred to the large coxal glands on the tenth legs where they are formed into spermatophores by a secretion. The spermatophores would then be picked up by the gonopods and by them inserted into the female vulvae during mating. Supposed spermatophores have already been illustrated in, for example, Trichopetalum dux (Chamberlin, 1940) on both the gonopods and attached to the female vulvae ( Shear 2003). In that case the spermatophores seemed to have a characteristic shape.

In the course of our SEM studies of Ochrogramma species, we found what we consider to be amorphous spermatophores or spermatophore material located in the tenth legpair coxal glands of males (sp, Fig. 48 View Figures 46–49 ) on the gonopods (sp, Fig. 30 View Figures 29–31 , 49 View Figures 46–49 ) and attached to the vulval valves of females (sp, Fig. 31 View Figures 29–31 , 47 View Figures 46–49 ). This is strong evidence that the theoretical sequence described in the paragraph above accurately describes what happens in the mating of chordeumatid species. The secretion forming the spermatophores is extremely sticky, or may have been hardened by preservation in alcohol. As can be seen from the illustrations, it could not be removed by ultrasonic cleaning.