Notoplana longiducta Hyman, 1959

Rodríguez, Jorge, Hutchings, Pat A. & Williamson, Jane E., 2021, Biodiversity of intertidal marine flatworms (Polycladida, Platyhelminthes) in southeastern Australia, Zootaxa 5024 (1), pp. 1-63 : 43-44

Notoplana longiducta Hyman, 1959

( Fig. 16 )

Notoplana longiducta Hyman, 1959: 10 , figs 12, 13.

Notoplana longicrumena Prudhoe, 1982: 369–370 , fig. 4.

Notocomplana longiducta Faubel, 1983: 114 .

Material examined: One specimen sagittally sectioned. AM W.53210 (4 slides). A specimen was collected at low tide under rocks from Australia, New South Wales, Bottle & Glass, 33°50’53.9”S, 151°16’12.3”E. Coll. Jorge Rodriguez and Justin McNab, October 25 th, 2019. Additional material from Australia, New South Wales, Long Reef from the collections of the Australian Museum : AM W.3693 (holotype), W.3694 .

Notoplana longicrumena Prudhoe, 1982 . One specimen from the collections of the Australian Museum, sagittally sectioned. AM W.53211 (8 slides). The specimen was collected from Australia, Tasmania, Pirates Bay Reef , March 7 th, 1958. Additional material from Australia, South Australia, Point Brown from the collections of the South Australian Museum : AHC.42652–42668 (holotype) .

Remarks: Externally, Notoplana longiducta Hyman, 1959 possesses an elongated body shape with a pale brown dorsal colouration, a transparent body margin and an anteriorly positioned pharynx ( Fig. 16A–D ). Internally, N. longiducta is characterised by the presence of a seminal vesicle, interpolated prostatic vesicle lined with tubularly chambered glandular epithelium, a very elongated penis stylet and a simple female system with a vertically oriented Lang’s vesicle ( Fig. 16E–I ).

Hyman (1959) mentions the poor state of the male copulatory system in the histological sections and the difficulties it caused in reconstructing its anatomy. In the original description Hyman (1959) describes Notoplana longiducta as having an elongated and pointed penis papilla; however, a revision of the type material made clear that what was described as a penis papilla was in fact a fold of the male atrium ( Fig. 16I ). Hyman (1959) mentions not only that the histological sections are in poor condition but that the cuts were not performed in an exact sagittal plane, which explains the misidentification of this trait. It was also apparent in both the holotype and the specimen from Bottle & Glass that this species presents a stylet in its male copulatory organ, although it was overlooked in the original description due to the poor condition of the type material ( Fig. 16I ).

Faubel (1983) transferred Notoplana longiducta to the new genus Notocomplana created for Notoplana species not bearing a stylet. However, a re-examination of the holotype and new material revealed the presence of such trait in the male copulatory organ. As such, the present species was transferred back to Notoplana under the original combination Notoplana longiducta .

Prudhoe (1982) described the new species Notoplana longicrumena from Point Brown, South Australia based on the presence of a long and slender penis stylet. Re-examination of the type material showed that the internal anatomy was identical to that of N. longiducta in light of the new description ( Fig. 16G ). As such, the primary authority belongs to Hyman (1959) and N. longicrumena was synonymised with N. longiducta .

Distribution: Australia: New South Wales, Long Reef ( Hyman 1959), South Australia, Point Brown ( Prudhoe, 1982).

New record: Australia, Tasmania, Pirates Bay Reef.

Figures

FIGURE 16. Notoplana longiducta Hyman, 1959. A. Dorsal view of live specimen. B. Details of the pharynx. C. Details of the reproductive systems. D. Arrangement of the eyes. E. Sagittal reconstruction of the reproductive system. F. Histological sections of the reproductive system of the specimen from Bottle & Glass. G. Histological sections of the holotype of Notoplana longicrumena Prudhoe, 1982. H. Histological sections of the specimen from Tasmania I. Histological sections of the holotype of Notoplana longiducta Hyman, 1959.