Family MASTIGIIDAE Stiasny, 1921

Museums

Regional Maps

Introduction

The family Mastigiidae comprises three genera, Mastigias L. Agassiz, 1862, Mastigietta Stiasny, 1921 and Phyllorhiza L. Agassiz, 1862. Species of all three genera are common in Australian waters. In particular, Phyllorhiza punctata is one of the most dominant rhizostomes in Australian waters (especially near Perth); species of Mastigias and Mastigietta are well represented across the tropical north.

The family is characterised by having broad subgenital ostia, annular subumbrellar muscles; short, pyramidal, three-winged oral arms; and, filaments on the arm disk. Most species in the family have a brownish colouration with conspicuous white spots.

The genera are easily confused, and indeed, there is much morphological overlap. Debate exists as to whether the genera represent real divisions in the group, or whether the group is much more homogeneous than currently estimated. The differences between the genera Phyllorhiza and Mastigias have been questioned; it seems plausible that the two may be synomynised one day, with the name Mastigias having nomenclatural priority. According to Kramp (1961b), the last to provide any sort of meaningful taxonomic guidance on the group, the genera can be identified as follows (see generic sections for more complete diagnoses):

Mastigias: oral arms terminate in a naked, club-shaped extremity; numerous small clubs and filaments between the frilled mouths present; mouths not only along the three edges of the oral arms, but also on their flat, expanded sides.

Mastigietta: oral arms lack appendages.

Phyllorhiza: lower parts of the oral arms with numerous filaments; lateral membranes of the oral arms with large window-like openings.

Diagnosis

Kolpophorae with annular subumbrellar muscles. With eight rhopalar radial canals. With ring canal. With a continuous genital porticus. Subgenital ostia very broad. Arm-disk quadratic, with four primary canals. With short, pyramidal, three-winged mouth-arms; with filaments on the arm-disk.

Diagnosis References

Kramp, P.L. 1961. Synopsis of the medusae of the world. Journal of the Marine Biological Association of the United Kingdom 40: 1-469 [357]

General References

Kramp, P.L. 1961. Synopsis of the medusae of the world. Journal of the Marine Biological Association of the United Kingdom 40: 1-469

History of changes