Family DIAZONIDAE


Compiler and date details

P. Kott, Queensland Museum, Brisbane, Queensland, Australia

Introduction

Members of the family Diazonidae Seeliger, 1906, are characterised by their large pharynx with numerous stigmata and longitudinal branchial vessels, vertical gut loop posterior to the pharynx, oviparous habit, and gonads usually enclosed by, but sometimes behind, the gut loop.

Rhopalaea Philippi, 1843 is a solitary genus, but others form colonies with zooids either partially or completely embedded. Replication occurs by transverse division of the abdomen, and is initiated by constriction of the ectoderm in a process similar to that of most other aplousobranch families. The regenerative tissue is the endodermal epicardium. Larvae, like those of Ciona Fleming, 1822 (family Cionidae), are small and primitive with three simple, sessile, triradially arranged adhesive organs.

The family is not especially diverse, nor are its members generally recorded in particularly dense populations. Apart from two species of Rhopalaea (one of which, R. crassa, is particularly abundant in tropical waters), the genus is represented in Australian waters only by Pseudodiazona claviformis (Kott, 1963), although Syndiazona Oka occurs in the western Pacific and in due course may be found to occur in tropical waters off this continent. The Antarctic genera Tylobranchion Herdman, 1886 and Pseudodiazona Millar, 1963 have a posterior abdomen, suggesting an affinity with the family Protopolyclinidae Kott, 1990.

 

General References

Fleming, J. 1822. Philosophy of Zoology; or a general view of the structure, functions, and classifications of animals. Edinburgh : Hurst Vol. 2 618 pp.

Herdman, W.A. 1886. Report on the Tunicata collected during the voyage of H.M.S. Challenger during the years 1873–1876. Pt II, Ascidiae compositae. Report on the Scientific Results of the Voyage of H.M.S. Challenger 1873–1876, Zoology 14(38): 1-425

Kott, P. 1963. The ascidians of Australia IV. Aplousobranchiata Lahille; Polyclinidae Verrill (continued). Australian Journal of Marine and Freshwater Research 14(1): 70-118

Kott, P. 1990. The Australian Ascidiacea Pt 2, Aplousobranchia (1). Memoirs of the Queensland Museum 29(1): 1-266

Millar, R.H. 1963. Australian ascidians in the British Museum (Natural History). Proceedings of the Zoological Society of London 141(4): 689-746

Philippi 1843. Rhopalaea eine neues genus der einfachen Ascidien. Archiv für Anatomie und Physiologie, Leipzig 1: 45-47

Seeliger, O. 1906. Appendicularien und Ascidien, Tunicata. Manteltiere. pp. 1041-1168 in Bronn, H.G. (ed.). Klassen und Ordnungen des Tier-Reichs. Leipzig : C.F. Winter Vol. 3 Suppl.

 

History of changes

Note that this list may be incomplete for dates prior to September 2013.
Published As part of group Action Date Action Type Compiler(s)
14-Dec-2012 14-Dec-2012 MODIFIED
12-Feb-2010 (import)

Genus Pseudodiazona Millar, 1963

 

Taxonomic Decision for Synonymy

 

Distribution

States

New South Wales, South Australia, Victoria, Western Australia


Extra Distribution Information

Abyssal east Atlantic Ocean.


Note that conversion of the original AFD map of states, drainage basins and coastal and oceanic zones to IBRA and IMCRA regions may have produced errors. The new maps will be reviewed and corrected as updates occur. The maps may not indicate the entire distribution. See further details below.

IMCRA

Great Australian Bight Shelf Transition (32), Spencer Gulf Shelf Province (33), Western Bass Strait Shelf Transition (34), Bass Strait Shelf Province (35), Southeast Shelf Transition (37), Central Eastern Shelf Province (38), Southern Province (8)

Original AFD Distribution Data

Australian Region

Distribution References

History of changes

Note that this list may be incomplete for dates prior to September 2013.
Published As part of group Action Date Action Type Compiler(s)
14-Dec-2012 14-Dec-2012 MODIFIED
12-Feb-2010 (import)

Species Pseudodiazona claviformis (Kott, 1963)

 

Taxonomic Decision for Synonymy

 

Distribution

States

New South Wales, South Australia, Victoria


Note that conversion of the original AFD map of states, drainage basins and coastal and oceanic zones to IBRA and IMCRA regions may have produced errors. The new maps will be reviewed and corrected as updates occur. The maps may not indicate the entire distribution. See further details below.

IMCRA

Great Australian Bight Shelf Transition (32), Spencer Gulf Shelf Province (33), Western Bass Strait Shelf Transition (34), Bass Strait Shelf Province (35), Southeast Shelf Transition (37), Central Eastern Shelf Province (38)

Original AFD Distribution Data

Australian Region

Ecological Descriptors

Benthic, marine, rock bottom.

Extra Ecological Information

10–100 m.

 

History of changes

Note that this list may be incomplete for dates prior to September 2013.
Published As part of group Action Date Action Type Compiler(s)
14-Dec-2012 14-Dec-2012 MODIFIED
12-Feb-2010 (import)

Species Pseudodiazona longigona Kott, 2008

 

Distribution

States

Western Australia


IMCRA

Southern Province (8)

History of changes

Note that this list may be incomplete for dates prior to September 2013.
Published As part of group Action Date Action Type Compiler(s)
11-Dec-2012 ADDED

Genus Rhopalaea Philippi, 1843

 

Taxonomic Decision for Synonymy

 

Distribution

States

Queensland, Western Australia


Extra Distribution Information

Mediterranean Sea, tropical Indo-West Pacific Ocean, west Atlantic Ocean.


Note that conversion of the original AFD map of states, drainage basins and coastal and oceanic zones to IBRA and IMCRA regions may have produced errors. The new maps will be reviewed and corrected as updates occur. The maps may not indicate the entire distribution. See further details below.

IMCRA

Central Western Shelf Province (29), Southwest Shelf Transition (30), Southwest Shelf Province (31), Central Eastern Shelf Transition (39), Northeast Shelf Province (40), Northeast Shelf Transition (41)

Original AFD Distribution Data

Afrotropical Region

Australian Region

Oriental Region

Palaearctic Region

Distribution References

History of changes

Note that this list may be incomplete for dates prior to September 2013.
Published As part of group Action Date Action Type Compiler(s)
14-Dec-2012 28-Aug-2014 MODIFIED
12-Feb-2010 (import)

Species Rhopalaea crassa (Herdman, 1880)

 

Taxonomic Decision for Synonymy

 

Distribution

States

Queensland, Western Australia


Note that conversion of the original AFD map of states, drainage basins and coastal and oceanic zones to IBRA and IMCRA regions may have produced errors. The new maps will be reviewed and corrected as updates occur. The maps may not indicate the entire distribution. See further details below.

IMCRA

Central Western Shelf Province (29), Southwest Shelf Transition (30), Southwest Shelf Province (31), Central Eastern Shelf Transition (39), Northeast Shelf Province (40), Northeast Shelf Transition (41)

Original AFD Distribution Data

Afrotropical Region

Australian Region

Oriental Region

Palaearctic Region

Ecological Descriptors

Benthic, marine.

Extra Ecological Information

Common in coral reef habitats.

 

General References

Kott, P. 2003. New syntheses and new species in the Australian Ascidiacea. Journal of Natural History 37: 1611-1653 [1613]

 

History of changes

Note that this list may be incomplete for dates prior to September 2013.
Published As part of group Action Date Action Type Compiler(s)
14-Dec-2012 14-Dec-2012 MODIFIED
12-Feb-2010 (import)

Species Rhopalaea tenuis (Sluiter, 1904)

 

Distribution

States

Queensland


Note that conversion of the original AFD map of states, drainage basins and coastal and oceanic zones to IBRA and IMCRA regions may have produced errors. The new maps will be reviewed and corrected as updates occur. The maps may not indicate the entire distribution. See further details below.

IMCRA

Central Eastern Shelf Transition (39), Northeast Shelf Province (40), Northeast Shelf Transition (41)

Original AFD Distribution Data

Australian Region

Oriental Region

Ecological Descriptors

Benthic, marine.

 

General References

Kott, P. 1990. The Australian Ascidiacea Pt 2, Aplousobranchia (1). Memoirs of the Queensland Museum 29(1): 1-266

 

History of changes

Note that this list may be incomplete for dates prior to September 2013.
Published As part of group Action Date Action Type Compiler(s)
14-Dec-2012 14-Dec-2012 MODIFIED
12-Feb-2010 (import)