Doliolum Nationalis Family Doliolidae Borgert, 1893

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Phylum Chordata Order Doliolida Doliolum nationalis Family Doliolidae Borgert, 1893 Synonoyms None M4 Size M3 M5 Gonozooid length up to 4 mm M2 M6 M7 Genus notes M1 • Dextral arched intestine M8 Species notes Gonozooid (Blastozooid) • 8 muscle bands in parallel transverse rings • Gill slits arched from M2 dorsally to M5 and turn slightly forward to finish just in front of M5 • Endostyle short, from M2 to M4 • Testis is variable in length, it extends horizontally, behind M4, on the left dextral arched intestine side of the animal • Differentiated from D. denticulatum which has longer testes in front of M3. testes gill slits stretch from M2 to M5 The form of the gill slits and gill location is also diagnostic. Distribution • Distribution in North and Central Atlantic Ocean, Mediterranean Sea, Red Sea, subtropical SW Atlantic Ocean, tropical Indian and W Pacific Oceans Ecology Godeaux (1998); Boltovskoy (2005) endostyle gills dextral arched gills intestine end here Live specimen North Stradbroke Island, Queensland Compiled: C. H. Davies & A. S. Slotwinski 2012 Verified: Phylum Chordata Doliolum nationalis Order Doliolida Borgert, 1893 Family Doliolidae Synonyms None Size Nurse length up to 2 mm No other sizes available Example of Doliolum larvae Genus notes No ampulla These stages of D. denticulatum and D. nationalis cannot be separated Larvae • Body fusiform • With tail • No ampulla Nurses • Barrel shaped, without visceral mass, except for heart Example of Doliolum nurse • M2-M8 fused in continuous sheet • Budding on the dorso-ventral process Dorso ventral process Oozooids • Endostyle from M2 to M5 • 9 muscle bands in parallel transverse rings • Dorso-ventral process at M7 • Intestinal tube stretched sagittally Example of Doliolum oozoid Source Boltovskoy (2005) endostyle Intestinal tube Couwelaar (2003) Godeaux (1998) Godeaux (1998) (Full reference available at http://www.imas.utas.edu.au/zooplankton/references Compiled: C. H. Davies & A. S. Slotwinski 2012 Verified:.

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