Placobdella kwetlumye, Oceguera-Figueroa & Kvist & Watson & Sankar & Overstreet & Siddall, 2010

Oceguera-Figueroa, Alejandro, Kvist, Sebastian, Watson, Sara C., Sankar, Dominic F., Overstreet, Robin M. & Siddall, Mark E., 2010, Leech Collections from Washington State, with the Description of Two New Species of Placobdella (Annelida: Glossiphoniidae), American Museum Novitates 2010 (3701), pp. 1-16 : 4-6

Placobdella kwetlumye , new species

Figures 2–6

MATERIAL EXAMINED: Two specimens collected in Squires Lake, Washington on September 30, 2009, by Alejandro Oceguera-Figueroa and Sebastian Kvist. Collected from the legs of AOF and on the underside of submerged rocks and wood.

DESCRIPTION: External morphology based on two specimens. Body dorsoventrally flattened, lanceolate, brownish tegument. Average body length 17.75 (14.60–20.90), average body width 4.70 (4.60–4.80). Complete somite triannulate, partially subdivided in somites at middle of body. Somites I and II uniannulate; III–IV biannulate; V–XXIV triannulate; XXV–XXVI biannulate; XXVII uniannulate. Two pair eyespots on III in “placobdellid” arrangement (i.e., in which the anterior most eyespots are coalesced medially to each other and posteriorly to the second pair). Oral sucker small, mouth pore on anterior border. Posterior sucker circular with papillae on dorsal surface. Anus located on dorsal surface of XXVII. Solid longitudinal stripe in midline of dorsal surface from V to XXIV, partially interrupted by large papillae and replaced by unpigmented medial stripe in most anterior somites. Dorsum with seven rows of papillae. Large papillae forming five longitudinal rows, prominent papillae on a2. Medial and lateral rows more conspicuous than marginal rows. Minor paramedial rows formed of medium-sized papillae bilaterally in the area between medial and lateral rows. From XXV–XXVII minor paramedial rows only are prominent. Dorsal surface not occupied by large and medium papillae, covered with punctiform, evenly distributed papillae (fig. 2). Ventral surface smooth and brownish, without metameric stripes, papillae or spots (figs. 3–4). Male gonopore between XI and XII. Female gonopore at XII a2/a3; two annuli between gonopores.

Internal morphology based on one dissected specimen. Proboscis large, in membranous sheath extending posteriorly to XI when retracted, unlooped. One pair well-developed anteromedial compact salivary glands extending from IXa3 to XI, discharging into base of proboscis. Posterolateral salivary glands absent. Esophagus short, folded, with one pair elongated mycetomes extending anteriorly from XI/XII to X a2 (fig. 5). Crop with seven pairs foliaceous caeca, last pair forming well-developed postcaeca (diverticula) extending posteriorly to XXV. Intestine with four pairs simple caeca in XX–XXIII. Male reproductive system with well-developed atrial cornua and highly coiled ejaculatory ducts. Six pairs intersegmental testisacs from XIII/XIV to XVIII/XIX. Ovisacs without common oviduct, anteriorly bilobed, extending posteriorly to XVII, anterior ovisac bifurcation at XIII/XIV. Anterior lobe extending anteriorly to XIII (fig. 6).

HOLOTYPE: Dissected, fixed in ethanol. 20.9 length, 5.0 maximum width. Collected by Alejandro Oceguera-Figueroa on September 30, 2009 ( AMNH 5527 ).

TYPE LOCALITY: Squires Lake , Whatcom County, Washington , 48°39′ 36.98″N; 122°20′ 02.76″W.

PARATYPE: One undissected specimen fixed in ethanol, collected by Sebastian Kvist, Squires Lake , Whatcom County, Washington, 48°39′ 36.98″N; 122°20′ 02.76″W, on September 30, 2009 ( AMNH 5528 ) .

ADDITIONAL MATERIAL: Thirteen specimens fixed in ethanol collected by Robin M. Overstreet. Some specimens found free living, some feeding from the cloaca of a gadwall ( Anas strepera ) in Summer Lake Wildlife Area, Lake County, Oregon, on August 14, 2002.

REMARKS: This species stands apart from all other species of Placobdella by its possessing a single pair of compact salivary glands. Siddall et al. (2005) and Siddall and Bowerman (2006) redefined the genus Placobdella to include species provided with two pairs of eyespots (with the anterior pair smaller and coalesced), with one pair of cecate mycetomes connected to the esophagus and with bilobate ovaries. The morphological characteristics found in P. kwetlumye , n. sp., are consistent with that definition. Placobdella kwetlumye , n. sp., resembles other papillated members of the genus described for North America: Placobdella burresonae Siddall and Bowerman, 2006 , Placobdella multilineata Moore, 1953 , Placobdella ali Hughes and Siddall, 2007 , Placobdella ornata (Verrill, 1872) , and Placobdella papillifera (Verrill, 1872) . However, the new species is easily distinguished from the last three of these owing, among other things, to the pattern of papillation. Placobdella ali , P. ornata , and P. papillifera present highly papillated dorsal surfaces, not forming well-structured rows like those present in P. burresonae , P. multilineata , and P. kwetlumye , n. sp. In addition, those highly papillated species exhibit two pairs of well-developed compact salivary glands connecting to the base of the proboscis; P. kwetlumye , n. sp., is the only species of the genus lacking the posterior pair. Furthermore, P. ali and P. papillifera present ventral pigmentation patterns, completely absent in P. kwetlumye , n. sp.

Placobdella burresonae and P. multilineata are superficially the most morphologically similar species to P. kwetlumye , n. sp. However, some differences in the external as well as in the internal morphology can be recognized. Medial and paramedial dorsal rows in P. burresonae and P. multilineata are formed by papillae of different size in every single annulus (see fig. 1 in Siddall and Bowerman, 2006), whereas in P. kwetlumye , n. sp., rows are formed by prominent papillae only on a2. Moreover, no marginal furrows are present in P. burresonae in contrast with P. kwetlumye , n. sp. (which has marginal papillae instead).

ETYMOLOGY: The specific epithet is based on the Nlaka’pamux (an Interior Salish “Thompson group” language) word for “leech” or “bloodsucker,” k’wétł’um’ye. The species name should be pronounced “kwaitle-oom-yay.” The type locality of P. kwetlumye , n. sp., corresponds to a region inhabited by the Coast Salish, but because no word for “leech” could be found in the Coast Salish lexicon, we opted for the lexicon of the geographically closest group.

Figures

FIGURES 2–6. Placobdella kwetlumye, n. sp. 2. Paratype, dorsal view. 3. Paratype, ventral view. 4. Eggs attached to the venter, ventral view. 5. Illustration of the proboscis (p), compact salivary glands (s), and mycetomes (m), in dorsal view. 6. Illustration of the male and female reproductive systems, dorsal view; testisacs not shown. Scale bars = 5 mm.