Abstract
Two new otoplanid species, from the interstitial habitats of the North-Western Mediterranenan sea coast, are described. The specimens show the typical morphological peculiarities of the subfamily Otoplaninae ("Turbellaria", Otoplanidae), but clearly differ from other species described in this group. Otoplana labronica sp. nov. is characterized by a body length of 1.2–1.5 mm, different features of the testes and vitellaries, the male sclerotic apparatus composed of a median aculeus (52–53 μm long) and 16 peculiar spines (19–44 μm long). This new species has the smallest number of spines (17) and the smaller body length, in comparison to all the species of the genus. Otoplana falcataspina sp. nov. is characterized by a body length of 2.3–2.4 mm, distinctive dimensions and arrangement of the vitellaries, the male sclerotic apparatus composed of a median aculeus (50–51 μm long) and 20–21 spines (22–44 μm long). This new species has a limited body length, and only the sexually mature specimens of the new species O. labronica exhibit a smaller size. They were collected below the low water mark on the sandy beaches at Calambrone and Marina di Vecchiano (Pisa, Ligurian Sea, Italy), respectively.
References
Ax, P. (1956) Monographie der Otoplanidae (Turbellaria): Morphologie und Systematik. Akademie der Wissenschaften und der Literatur, Abhandlungen der Mathematisch-Naturwissenschaftlichen Klasse, 13, 159–278.
Ax, P. (1959) Zur Systematik, Ökologie und Tiergeographie der Turbellarienfauna in den Ponto-kaspischen Brackwassermeeren. Zoologische Jahrbücher Abteilung für Systematik, Ökologie und Geographie der Tiere, 87, 71–89.
Claus, C. (1887) Lehrbuch der Zoologie. Bd. 4. Auflage, N. G. Elwertsche Verlagsbuchhandlung, Marburg u.Leipzig. Cited from Ehlers & Sopott-Ehlers, 1995.
Du Plessis, G. (1889) Note sur l’Otoplana intermedia. Zoologischer Anzeiger, 12, 339–342.
Ehlers, U. (1984) Phylogenetisches System der Plathelminthes. Verhandlungen des Naturwissenschaftlichen Vereins in Hamburg (NF), 27, 291–294.
Ehlers, U. & Sopott-Ehlers, B. (1995) Plathelminthes or Platyhelminthes? Hydrobiologia, 305, 1–2. http://dx.doi.org/10.1007/BF00036354
Hallez, P. (1892) Classification des Triclades. Bulletin de la Société Zoologique de France, 17, 106–109.
Hallez, P. (1910) Un nouveau type d’Alloiocoele (Bothriomolus constrictus n. g. n. sp.). Archive de Zoologie Expérimentale et Générale, 3, 611–664.
Lanfranchi, A. (1969) Nuovi Otoplanidi (Turbellaria, Proseriata) delle coste della Liguria e della Toscana. Bollettino di Zoologia, 36, 167–188. http://dx.doi.org/10.1080/11250006909436914
Lanfranchi, A. (1978) Morphology and taxonomy of two new Otoplanids (Turbellaria, Proseriata) from the Ligurian Sea. Zoologica Scripta, 7, 249–254. http://dx.doi.org/10.1111/j.1463-6409.1978.tb00606.x
Lanfranchi, A. & Melai, M. (2007) Morphology and taxonomy of a new species of Otoplanid (Plathelminthes, Rhabditophora, Proseriata) from the Ligurian Sea. Italian Journal of Zoology, 74, 209–214. http://dx.doi.org/10.1080/11250000701286787
Lanfranchi, A. & Melai, M. (2010) A new marine flatworm (Plathelminthes: Rhabditophora: Otoplanidae) from the Ligurian coast. Journal of the Marine Biological Association of the United Kingdom, 90(2), 423–427. http://dx.doi.org/10.1017/S0025315409990427
Remane, A. (1933) Verteilung und Organisation der benthonischen Mikrofauna der Kieler Bucht. Wissenschaftliche Meeresuntersuchungen (N.F.), Abteilung Kiel, 21, 161–221.
Schneider, A. (1873) Untersuchungen über Plathelminthen. Separatabdruck aus d. 14. Jahresbericht Oberhessen Gesellschaft für Natur- und Heilkunde Giessen, 14, 1–78, Tables 3–7.
Tyler, S., Schilling, S., Hooge, M. & Bush, L.F. (comp.) (2006–2012) Turbellarian taxonomic database. Version 1.7 http://turbellaria.umaine.edu