Gordionus lokaaus Begay, Schmidt-Rhaesa, Bolek & Hanelt, 2012, n. sp.

Gordionus lokaaus n. sp.

(Figs. 1, 2)

Holotype. Deposited at the Museum of Southwestern Biology-Parasitology Division (MSB: PARA): 101. Male collected from a tributary of the North Fork Tesuque Creek (35.7699, -105.7954).

Paratypes. Allotype. MSB: PARA 102. Female collected from a tributary of the North Fork Tesuque Creek (35.7699, -105.7954). Other paratypes. MSB: PARA: 103–110.

Etymology. The species epithet is derived from the Navajo word for bamboo, lókaa’tsoh, which describes the hollow tube-shape formed by the spines surrounding the male’s cloaca (Fig. 1 C).

Distribution. Rocky Mountains, Santa Fe National Forest, New Mexico. Found at two sites (sites 1 and 2) consisting of unnamed first order streams crossing Aspen Vista road, off of NM State route 475 (Hyde Park road) near the Santa Fe ski area: Site 1 (35.7699, -105.7954) at an elevation between 3,200‒3,290m, and site 2 (35.7788, -105.7953) at an elevation of 3,127m.

Type locality. Site 1 (35.7699, -105.7954) at an elevation between 3,200‒3,290m.

Bionomics. The worms were collected in the free-living, post-parasitic, adult stage, and the paratenic and definitive hosts remain unknown. Most individuals of this species were collected from August to September (n = 51), and a few were collected in late June (n = 3).

Material examined. Of 54 worms (27 males; 27 females) collected, DNA was amplified for all individuals. For each of these worms, partial cox 1 was amplified and sequenced. The anterior, posterior, and midsection of seven individuals were used for SEM studies.

Description of male. Ađult males were 73‒22O (x = I4 I•2)mm lοng anđ white in cοlοr• Areοles οf οne type, mostly flat; ranging in shape from polygonal to round (Figs. 1 D and E). In some areas areoles have serrated edges (Fig. 1 D), while in others the margins appear much smoother (Fig. 1 E). Interareolar furrows are distinct.

On ventral side, areoles in some areas are much less defined and the surface appears grooved perpendicular to the longitudinal axis (Fig. 1 H). Tubercles are present but not abundant between areoles (megareolar pattern, Fig. 1 D, E); more abundant in anterior end. Precloacal bristles are long, conical and arranged into thin rows (Fig. 1 A); bristles branch apically (Fig. 1 G). Cloacal opening is surrounded by broad spines of irregular shape (Fig. 1 C), which together appear to form a tube; some spines appear to be branched slightly (Fig. 1 C). Postcloacal spines start immediately posterior to the cloacal opening and extend onto the inner side of the tail lobes (Figs. 1 A, B). Postcloacal spines appear thin and triangular; some with serrated edges (Fig. 1 B). Canoe-shaped adhesive warts are present anterior to the precloacal rows of bristles (Fig. 1 F), and are relatively narrow (8‒10µm).

Description of female. Ađult females were white anđ 52‒2OO (x = I42 •8) mm lοng• Areοles οf οne type mostly flat; range in shape from polygonal to round (Figs. 2 A and B). In some areas areoles have serrated edges (Fig. 2 B), while in others the margins appear smooth (Fig. 2 A). Round areoles predominate in the anterior end. Megareolar pattern present (Figs. 2 A and B) moderately throughout, but more abundant in anterior end. Most tubercles situated in hollows formed on the edges of areoles (Fig. 2 C).