Alfred Manta, Manta alfredi Click to enlarge image
An Alfred Manta at a depth of 10 m, Lady Elliot Island, Queensland, December 2011. Image: Richard Vevers
© Richard Vevers

Fast Facts

  • Classification
    Genus
    Mobula
    Species
    alfredi
    Family
    Mobulidae
    Order
    Myliobatiformes
    Class
    Chondrichthyes
    Subphylum
    Vertebrata
    Phylum
    Chordata
    Kingdom
    Animalia
  • Size Range
    The largest recorded individual had a disc width of just over 5 m.

Introduction

The Manta Ray, Mobula alfredi was named after Queen Victoria's son Prince Alfred, who survived an assassination attempt in Clontarf, Sydney in 1868.



Identification

Two species of Manta are known from Australian waters. The 2009 paper of Marshall and colleagues (see below) resurrected Mobula alfredi, which was originally described by Australian Museum Director Gerard Krefft in 1868, after the attempt on Prince Alfred's life.

Long thought to have been a single wide-ranging species, Manta birostris, the genus is now known to comprise two species. The Alfred Manta and the Manta Ray can be distinguished by a number of measurements but also by size, dentition and spine morphology.

The easiest way to distinguish live fish is by the presence of dark spots on the ventral surface medially between the gill slits of the Alfred Manta. The Manta Ray has no spots between the gill slits. The shape of the whitish-coloured shoulder patches is also a good character - those of the Alfred Manta "eminate from spiracle before curving medially" but those of the Manta Ray are "very distinct and approximately triangular in shape".

Dr Mike Bennett (see Marshall et.al, 2009 in References, below) stated that "The dorsal views are much more difficult to resolve as there is pretty large variability….but look for the lump at the tail base and that can be your quick check…..if it is there = birostris, absent = alfredi."



Distribution

The map below shows the Australian distribution of the species based on public sightings and specimens in Australian Museums. Click on the map for detailed information. Source: Atlas of Living Australia.



References

  1. Hoese, D.F., Bray, D.J., Paxton, J.R. & G.R. Allen. 2006. Fishes. In Beesley, P.L. & A. Wells. (eds) Zoological Catalogue of Australia. Volume 35. ABRS & CSIRO Publishing: Australia. parts 1-3, pages 1-2178.
  2. Marshall, A., Compagno, L.J.V. and Bennett, M.B. 2009. Redescription of the genus Manta with resurrection of Manta alfredi (Krefft, 1868) (Chondrichthyes; Myliobatoidei; Mobulidae). Zootaxa. 2301: 1-28.
  3. Whitley, G.P. 1936. Devil Ray! The Australian Museum Magazine. Pp 1-12.