- D. willana growing on Taieri Island, showing the distinctive branched stipe and dark colouration
- D. willana surrounded by other Durvillaea on Taieri Island, Otago
- Many D. willana growing at Watsons Beach, Otago
- Prepared specimen of D. willana
Durvillaea willana | |
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D. willana at Watsons Beach, Otago, with the epiphyte Pyrophyllon subtumens growing on the middle plant . | |
Scientific classification | |
Domain: | Eukaryota |
Clade: | Diaphoretickes |
Clade: | SAR |
Clade: | Stramenopiles |
Phylum: | Gyrista |
Subphylum: | Ochrophytina |
Class: | Phaeophyceae |
Order: | Fucales |
Family: | Durvillaeaceae |
Genus: | Durvillaea |
Species: | D. willana |
Binomial name | |
Durvillaea willana | |
Durvillaea willana is a large species of southern bull kelp endemic to New Zealand. [1] [2] [3] [4]
The species epithet, willana, honours Eileen Alice Willa who collected many algal species for Lindauer. [1]
This species is chocolate brown in colour and is darker than all other bull kelp species. [4] [5] It has a branched stipe. [3] The species is non-buoyant and does not have 'honeycomb' in its fronds. [3] [4] The holdfast becomes large and spreads like a plate on rocky substrates. [6]
This species is superficially similar in appearance to Durvillaea antarctica . [6] However, D. willana has smaller blades than D. antarctica and is usually found lower on the shoreline because its lower tolerance of wave action compared to D. antarctica. [6] It also has a branched stipe and does not have buoyant fronds, unlike D. antarctica. [3]
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. [1] [2] [3] [4] [7] [8]
Gaps in the geographic range of the species may have been caused by earthquake uplift events such as the 1855 Wairarapa earthquake. [4] 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. [8] This result suggests that the subtidal D. willana may not die-off completely due to earthquake uplift events. [8]
Kelps are large brown algae or seaweeds that make up the order Laminariales. There are about 30 different genera. Despite its appearance, kelp is not a plant but a stramenopile, a group containing many protists.
Nereocystis is a monotypic genus of subtidal kelp containing the species Nereocystis luetkeana. Some English names include edible kelp, bull kelp, bullwhip kelp, ribbon kelp, bladder wrack, and variations of these names. Due to the English name, bull kelp can be confused with southern bull kelps, which are found in the Southern Hemisphere. Nereocystis luetkeana forms thick beds on subtidal rocks, and is an important part of kelp forests.
The biodiversity of New Zealand, a large island country located in the south-western Pacific Ocean, is varied and distinctive. The species of New Zealand accumulated over many millions of years as lineages evolved in the local circumstances. New Zealand's pre-human biodiversity exhibited high levels of species endemism, but has experienced episodes of biological turnover. Global extinction approximately 65 Ma resulted in the loss of fauna such as non-avian dinosaurs, pterosaurs and marine reptiles e.g. mosasaurs, elasmosaurs and plesiosaurs. The ancient fauna is not well known, but at least one species of terrestrial mammal existed in New Zealand around 19 Ma. For at least several million years before the arrival of human and commensal species, the islands had no terrestrial mammals except for bats and seals, the main component of the terrestrial fauna being insects and birds. As recently as the 14th century a component has been introduced by humans, including many terrestrial mammals.
Alaria esculenta is an edible seaweed, also known as dabberlocks or badderlocks, or winged kelp, and occasionally as Atlantic Wakame. It is a traditional food along the coasts of the far north Atlantic Ocean. It may be eaten fresh or cooked in Greenland, Iceland, Scotland and Ireland. It is the only one of twelve species of Alaria to occur in both Ireland and in Great Britain.
Macrocystis is a monospecific genus of kelp with all species now synonymous with Macrocystis pyrifera. It is commonly known as giant kelp or bladder kelp. This genus contains the largest of all the Phaeophyceae or brown algae. Macrocystis has pneumatocysts at the base of its blades. Sporophytes are perennial and the individual may live for up to three years; stipes/fronds within a whole individual undergo senescence, where each frond may persist for approximately 100 days. The genus is found widely in subtropical, temperate, and sub-Antarctic oceans of the Southern Hemisphere and in the northeast Pacific from Baja California to Sitka, Alaska. Macrocystis is often a major component of temperate kelp forests.
Durvillaea is a genus of large brown algae in the monotypic family Durvillaeaceae. All members of the genus are found in the southern hemisphere, including Australia, New Zealand, South America, and various subantarctic islands. Durvillaea, commonly known as southern bull kelps, occur on rocky, wave-exposed shorelines and provide a habitat for numerous intertidal organisms. Many species exhibit a honeycomb-like structure in their fronds that provides buoyancy, which allows individuals detached from substrates to raft alive at sea, permitting dispersal for hundreds of days over thousands of kilometres. Durvillaea species have been used for clothing, tools and as a food source by many indigenous cultures throughout the South Pacific, and they continue to play a prominent role in Chilean cuisine.
Durvillaea antarctica, also known as cochayuyo and rimurapa, is a large, robust species of southern bull kelp found on the coasts of Chile, southern New Zealand, and Macquarie Island. D. antarctica, an alga, does not have air bladders, but floats due to a unique honeycomb structure within the alga's blades, which also helps the kelp avoid being damaged by the strong waves.
Onithochiton neglectus neglectus is a subspecies of chiton in the family Chitonidae.
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 to the epicentre, shaking lasted for at least 50 seconds. The moment magnitude of the earthquake has been estimated as 8.2, the most powerful recorded in New Zealand since systematic European colonisation began in 1840. This earthquake was associated with the largest directly observed movement on a strike-slip fault, maximum 18 metres (59 ft). This was later revised upward to about 20 m (66 ft) slip, with a local peak of 8 m (26 ft) vertical displacement on lidar studies. It has been suggested that the surface rupture formed by this event helped influence Charles Lyell to link earthquakes with rapid movement on faults.
The Founder Takes All (FTA) hypothesis refers to the evolutionary advantages conferred to first-arriving lineages in an ecosystem.
Ceridwen Fraser is a biogeographer, currently serving as a Professor in the Department of Marine Science at the University of Otago in Dunedin, New Zealand. She focuses her studies on ecology, evolution, climate change, and how they are all significant to the southern hemisphere, specifically at higher latitudes such as Antarctica.
Durvillaea poha is a large, robust species of southern bull kelp found in New Zealand.
Durvillaea amatheiae is a large, robust species of southern bull kelp found in Australia.
Durvillaea fenestrata is a large, robust species of southern bull kelp endemic to the subantarctic Antipodes Islands of New Zealand.
Durvillaea incurvata is a large, robust species of southern bull kelp endemic to Chile.
Durvillaea chathamensis is a large, robust species of southern bull kelp endemic to the Chatham Islands of New Zealand.
Durvillaea potatorum is a large, robust species of southern bull kelp found in Australia.
Pōhā are traditional Māori bags made from southern bull kelp, which are used to carry and store food and fresh water, to propagate live shellfish, and to make clothing and equipment for sports. Pōhā are especially associated with Ngāi Tahu, who have legally recognised rights for harvesting source species of kelp.
Pyrophyllon subtumens is an obligate red algal epiphyte of Durvillaea southern bull-kelp, and is endemic to New Zealand.
Maullinia is a genus of intracellular, phytomyxid parasites found across the Southern Hemisphere though primarily in Chile, The Prince Edward Islands, South Africa, Australia, and New Zealand. These parasites infiltrate the cells of their brown algal hosts via cytoplasmic extensions called plasmodia that divide synchronously, becoming increasingly multi-nucleate and engulfing the host cell organelles as they grow. Eventually, as the plasmodia fill the entire cell volume, the host cells become hypertrophied and grow to 3- 4x their original size, showing up as swollen appendages or galls on the host tissue at a macroscopic level. These swollen regions will burst alongside the mature Maullinia plasmodia, releasing biflagellated zoospores to the inter- and extracellular space to disperse the infection further. Zoospores can come from sporangial plasmodia, as in M. ectocarpii, or from resting spores, as in M. braseltonii.