''Durvillaea willana'' is a large species of southern bull kelp

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Etymology

The species epithet, ''willana'', honours

Eileen Alice Willa Eileen Alice Willa (1905–1999) was a New Zealand botanical collector, museum curator and writer. She was born Eileen Harrison on Stewart Island, and grew up with a love of botany. In 1928, she married Percy Willa and they settled at Halfmoon ...

who collected many algal species for Lindauer.

Description

This species is chocolate brown in colour and is darker than all other bull kelp species. It has a branched stipe. The species is non-buoyant and does not have 'honeycomb' in its fronds. The holdfast becomes large and spreads like a plate on rocky substrates. This species is superficially similar in appearance to ''

Durvillaea antarctica ''Durvillaea antarctica'', also known as ' and ', is a large, robust species of southern bull kelp found on the coasts of Chile, southern New Zealand, and Macquarie Island.Smith, J.M.B. and Bayliss-Smith, T.P. (1998). Kelp-plucking: coastal eros ...

''. However, ''D. willana'' has smaller blades than ''D. antarctica'' and is usually found lower on the shoreline because its lower tolerance of wave action comparded ''D. antarctica''. It also has a branched stipe and does not have buoyant fronds, unlike ''D. antarctica''.

Distribution

This species of kelp is endemic to New Zealand and is found on the southeastern shores of the North Island, although not in Cook Strait, as well as on the shores of the South Island and Stewart Island. Gaps in the geographic range of the species may have been caused by earthquake uplift events such as the

1855 Wairarapa earthquake The 1855 Wairarapa earthquake occurred on 23 January at about 9.17 p.m., affecting much of the Cook Strait area of New Zealand, including Marlborough in the South Island and Wellington and the Wairarapa in the North Island. In Wellington, close ...

. However, historic uplift (800 - 1400 years before present) in the Akatore fault zone does not seem to have caused any long term disruption in the genetic diversity of ''D. willana'', in that region. This result suggests that the subtidal ''D. willana'' may not die-off completely due to earthquake uplift events.

References

External links

Algaebase: ''Durvillaea'' Lindauer

Museum of New Zealand Te Papa Tongarewa: ''Durvillaea willana'' Lindauer (Species)
Fucales Flora of New Zealand {{Phaeophyceae-stub