Notocomplana septentrionalis (Kato, 1937)

Oya, Yuki & Kajihara, Hiroshi, 2017, Description of a new Notocomplana species (Platyhelminthes: Acotylea), new combination and new records of Polycladida from the northeastern Sea of Japan, with a comparison of two different barcoding markers, Zootaxa 4282 (3), pp. 526-542 : 536-539

Notocomplana septentrionalis (Kato, 1937)

( FigS. 4 C, 6, 7)

Notoplana septentrionalis Kato, 1937b : pp. 127–129, text-figs. 5, 6, pl. 8, figs. 4–6 [Muroran, Hokkaido, Japan]. Notocomplana septentrionalis: Faubel (1983) , p. 115 [secondary literature].

Material examined. Fourteen SpecimenS: eleven from OShoro (43°12′36″N, 140°51′28″E), Hokkaido, Japan, of which four ( ICHUM 5287 , Sagittal SectionS, 4 SlideS; ICHUM 5288 , croSS SectionS, 11 SlideS; ICHUM 5289 , Sagittal SectionS, 9 SlideS; ICHUM 5290 , Sagittal SectionS, 6 SlideS) were collected on 25 May 2015, one ( ICHUM 5294 , Sagittal SectionS, 9 SlideS) on 30 May 2016, and Six ( ICHUM 5295 , croSS SectionS, 7 SlideS; ICHUM 5296 , Sagittal SectionS, 8 SlideS; ICHUM 5297 , Sagittal SectionS, 7 SlideS; ICHUM 5298 , Sagittal SectionS, 7 SlideS; ICHUM 5299 , Sagittal SectionS, 9 SlideS; ICHUM 5300 , Sagittal SectionS, 9 SlideS) on 6 June 2016 ; and three SpecimenS ( ICHUM 5291 , Sagittal SectionS, 7 SlideS; ICHUM 5292 , Sagittal SectionS, 6 SlideS; ICHUM 5293 , whole Specimen preServed in 70% ethanol) from Zenibako (43°09′07″N, 141°11′16″E), Hokkaido, Japan, on 28 May 2016 .

Description. Live SpecimenS 12–23 mm in length, 5–9 mm in width. Body elongate oval, narrow toward poSterior end. Ground body color whitiSh. General appearance of body varying from yellowiSh khaki mottled with dark ( Fig. 6 A), to milky white with black dotS above pharynx ( Fig. 7 A), to uniform chocolate color ( Fig. 7 B); in each form, dorSal Surface above pharynx appearing darker, with Scattered Small, brown granuleS. Body margin tranSlucent. Pharynx white, ruffled in Shape, occupying three-SeventhS to one-half of body length. InteStine highly branched and not anaStomoSing, Spreading throughout body except margin and brain region. Mature eggS whitiSh, within pair of oviductS viSible through ventral body Surface ( Fig. 6 B). Pair of whitiSh Sperm ductS alSo viSible in mature animalS. Male and female gonoporeS Separate; male gonopore opening at about one-fifth body length from poSterior end; female gonopore Situated poSterior to male gonopore ( Fig. 6 B).

Pair of Small tentacular knobS preSent at one-fifth of body length from anterior end but hardly viSible in aneSthetized State. Tentacular eye cluSterS conSiSting of 26–78 eyeSpotS ( Fig. 6 C). Cerebral eye cluSterS, arranged along median line and congregated anterior to tentacleS, conSiSting of 24–81 eyeSpotS ( Fig. 6 C).

Male copulatory apparatuS conSiSting of true Seminal veSicle, interpolated proStatic veSicle, and peniS papilla ( FigS. 4 C), 6D, located immediately poSterior to pharynx. Pair of Sperm ductS running anteriorly, turning medially at point of about one-fourth of pharynx length from poSterior end of pharynx, curving poSteriorly along both SideS of pharynx, and continuing beyond level of poSterior end of pharynx for Short diStance, before turning medially to enter Separately proximal end of bean-Shaped Seminal veSicle ( Fig. 4 C), latter having Strong muScular wall. IntraproStatic ejaculatory duct projecting deeply and diStally into pear-Shaped proStatic veSicle. CanalS of numerouS extra-veSicular glandS penetrating wall of proStatic veSicle. ProStatic veSicle with Strong muScular wall, and with 11 longitudinal tubular chamberS (n = 2; confirmed in tranSverSely Sectioned SpecimenS) Surrounding ejaculatory duct ( Fig. 6 E). PoSt-proStatic ejaculatory duct leading to peniS papilla, latter muScular, conical, without Stylet, projecting into narrow male atrium. Lining epithelium of male atrium ciliated and folded ( Fig. 6 F, G).

Pair of oviductS commencing from level of anterior end of pharynx, running poSteriorly ( Fig. 6 B), then extending beyond level of poSterior end of pharynx for Short diStance before curving medially and fuSing at midline to form common oviduct, which runS upward to enter vagina ( Fig. 6 H). From thiS point, Lang’S duct, lined with ciliated epithelium, leading poSteriorly to Lang’S veSicle, latter being elongate, lined with columnar cellS ( Fig. 6 H). Vagina lined with Smooth and ciliated epithelium, curving downward for Short diStance, then turning backward before curving ventrally to exit perpendicularly at female gonopore. Vagina and Lang’S duct Surrounded by circular muScle fiberS; vagina Surrounded by numerouS cement glandS.

Habitat. Kato (1937b) did not mention detailS about the habitat. Our SpecimenS were collected from bedS of Mytilus Spp. muSSelS ( M. galloprovincialis Lamarck, 1819 and/or M. trossulus Gould, 1850 ) in the intertidal zone and from concrete blockS forming a breakwater.

Remarks. Kato (1937b) originally deScribed thiS SpecieS from Muroran, Hokkaido, Japan. Our SpecimenS are conSiStent with the original deScription in that i) the Small tentacleS are preSent, ii) the Sperm ductS Separately enter the Seminal veSicle, iii) the intra-proStatic ejaculatory duct projectS deeply into the proStatic veSicle, iv) the vagina iS directed dorSo-anteriorly from the female gonopore, then curveS backward, v) the vaginal epithelium iS folded, and vi) the Lang’S veSicle iS poSteriorly elongate.

The male atrial epithelium varied among individualS from weakly ( Fig. 6 F) to extenSively ( Fig. 6 G) folded. The foldS in the type material illuStrated by Kato (1937b, text-fig. 6) fall within the range of variation we obServed. The variation of thiS Study doeS not correlate to the body Size and maturity in our SpecimenS.

Figures

FIGURE 4. Diagrams showing the copulatory complex. A. Notocomplana japonica (Kato, 1937) comb. nov. B. Notocomplana koreana (Kato, 1937). C. Notocomplana septentrionalis (Kato, 1937). All anterior to the right. Abbreviations: cov, common oviduct; csd, common sperm duct; fg, female gonopore; ied, intra-prostatic ejaculatory duct; ld, Lang’s duct; lv, Lang’s vesicle; ma, male atrium; mg, male gonopore; ov, oviduct; ped, post-prostatic ejaculatory duct; pp, penis papilla; pv, prostatic vesicle; sd, sperm duct; sv, seminal vesicle; v, vagina.

FIGURE 6. Notocomplana septentrionalis (Kato, 1937). A. Dorsal view in the living state, ICHUM 5292 (non-type). B. Ventral view in the living state, ICHUM 5292 (non-type). C. Eyespots in the living state, ICHUM 5292 (non-type). D. Sagittal section of the male copulatory apparatus, anterior to the right, ICHUM 5292 (non-type). E. Cross section of the male copulatory apparatus, ICHUM 5295 (non-type). F. Weakly folded epithelium of the male atrium, ICHUM 5291 (non-type). G. Extensively folded epithelium of the male atrium, ICHUM 5294 (non-type). H. Sagittal section of the female copulatory apparatus, anterior to the right, ICHUM 5292 (non-type). Abbreviations: cec, cerebral eye cluster; cg, cement glands; cov, common oviduct; exc, extra-vesicular gland’s canal, fg, female gonopore; ied, intra-prostatic ejaculatory duct; ld, Lang’s duct; lv, Lang’s vesicle; ma, male atrium; mg, male gonopore; ov, oviduct; ped, post-prostatic ejaculatory duct; ph, pharynx; pp, penis papilla; pv, prostatic vesicle; sv, seminal vesicle; tec, tentacular eye cluster; v, vagina.

FIGURE 7. Notocomplana septentrionalis (Kato, 1937) in the living state, showing two color varieties. A. ICHUM 5289 (nontype). B. ICHUM 5298 (non-type).