Wendy A Nelson

• PhD
• Professor at University of Auckland

Crustose coralline algae (CCA) are a highly diverse group of habitat‐forming, calcifying red macroalgae (Rhodophyta) with unique adaptations to diverse irradiance regimes. A distinctive CCA phenotype adaptation, which allows them to maximize photosynthetic performance in low light, is their content of a specific group of light‐harvesting pigments c...

Biogenic habitats are foundational habitats for species assemblages and drive a range of ecosystem functions. The Hauraki Gulf/Tiikapa Moana is the most intensively used coastal area in Aotearoa/New Zealand, and decades of commercial fishing, sedimentation and industrialization have degraded biogenic habitats in the Gulf. In response, the marine sp...

The giant kelp Macrocystis pyrifera is in global decline as a result of numerous stressors operating on both local and global scales. It is a species that holds significant value in terms of the ecosystem services that it provides and its application in aquaculture. In order to safeguard, restore and utilize this species, it is essential that a sou...

The waters of Aotearoa New Zealand span over 4.2 million km2 of the South Pacific Ocean and harbour a rich diversity of seafloor-associated taxa. Due to the immensity and remoteness of the area, there are significant gaps in the availability of data that can be used to quantify and map the distribution of seafloor and demersal biodiversity, limitin...

Global marine conservation remains fractured by an imbalance in research efforts and policy actions, limiting progression towards sustainability. Rhodolith beds represent a prime example, as they have ecological importance on a global scale, provide a wealth of ecosystem functions and services, including biodiversity provision and potential climate...

A new genus in the Dictyotales, Lindauera, is described based on the species Dictyota papenfussii Lindauer from Taranaki, North Island, New Zealand. Lindauera is distinguished from Dictyota by both molecular data and by the possession of primary, prostrate dichotomously branched axes that attach thalli to substrates. We present data extending the k...

Coralline algae are an essential element of benthic ecosystems throughout the ocean's photic zone. Yet, the role of light in shaping the physiology of coralline algae from cold-water, low-light habitats is poorly understood. Here, we assess the calcification physiology of five cool temperate coralline algae in response to different irradiance level...

Introduced seaweeds and undescribed species often remain undetected because marine regional floras are as yet poorly understood. DNA sequencing facilitates their detection, but databases are incomplete, so their improvement will continue to lead the discovery of these species. Here we aim to clarify the taxonomy of two turf-forming red algal Austra...

A molecular phylogeny of Tinocladia and Eudesme based on specimens covering a large proportion of the known species was done using mitochondrial cox1 and cox3, chloroplast atpB, psaA, psbA and rbcL genes and 5.8S rDNA and its ITS2 region sequences. The phylogeny revealed a close phylogenetic relationship between the two genera and the occurrence of...

The waters of Aotearoa New Zealand span over 4.2 million km2 of the South Pacific Ocean and harbour a rich diversity of seafloor associated taxa. Due to the immensity and remoteness of the area, there are significant gaps in the availability of data to quantify and map the distribution of seafloor and demersal biodiversity, limiting effective manag...

The carrageenophyte red alga Sarcothalia radula (Gigartinaceae), referred to under its earlier name Gigartina radula, is one of eight species considered a safe source of the refined hydrocolloid and food additive carrageenan and is also reported to be a source of compounds of interest in a variety of other commercial applications. While the latter...

Ocean warming (OW) and marine heatwaves (MHWs) rapidly transform marine ecosystems, especially when they impact keystone or foundation species. Foundation species such as kelps, fucoids and corals are highly sensitive to heat stress, which threatens the future of temperate seaweed forests and tropical reefs. However, functioning and resilience of t...

Phylogenetic analyses resolved that specimens from Manawatāwhi/Three Kings Islands in northern New Zealand, formerly identified as Sonderophycus coriaceus, belong to the genus Agissea (Peyssonneliales). This species is dark red, prostrate and robust, with leathery, fan-shaped lobes and is described here as Agissea teruruhau. It was found to serve a...

Coralline algae are ecologically important macroalgae providing settlement cues and habitat for a number of marine organisms. They are abundant in a wide range of habitats in tropical to polar systems and are at severe risk from a number of local and global anthropogenic stressors. Despite their ecological importance, there are large gaps in unders...

https://global-ecosystems.org/explore/groups/M1.10

Gracilaria chilensis is the main cultivated seaweed in Chile. The low genetic diversity observed in the Chilean population has been associated with the over‐exploitation of natural beds and/or the founder effect that occurred during the post‐glacial colonization from New Zealand. How these processes have affected its evolutionary trajectory before...

To support ongoing marine spatial planning in New Zealand, a numerical environmental classification using Gradient Forest models was developed using a broad suite of biotic and high-resolution environmental predictor variables. Gradient Forest modeling uses species distribution data to control the selection, weighting and transformation of environm...

Molecular techniques have become important tools to investigate cryptic diversity and phylogeographic patterns. Mitochondrial markers have revealed that the temperate red alga Asparagopsis armata contains two cryptic clades. The A. armata species complex is native to Australia and New Zealand and has been introduced around the world, particularly t...

2020. The biogeographical importance of buoyancy in macroalgae: A case study of the southern bull-kelp genus Durvillaea (Phaeophyceae), including descriptions of two new species. J. Phycol. 56:23-36.

A multi‐gene (psbA, rbcL, 18S rDNA) molecular phylogeny of the genus Phymatolithon showed a polyphyletic grouping of two monophyletic clades within the Hapalidiales. DNA sequence data integrated with morpho‐anatomical comparisons of type material and of recently collected specimens were used to establish Phymatolithopsis gen. nov. with three specie...

The recognition of non-indigenous marine macroalgae in New Zealand and the potential pathways and vectors contributing to their arrival were discussed by Nancy Adams in 1983 along with a list of 14 species she considered to be “possibly naturalised”. In the following 38 years many more species have been identified as non-indigenous, a few of which...

Manawatāwhi/Three Kings Islands lie to the north of the North Island of New Zealand. Manawatāwhi is part of the rohe (territory) of Ngāti Kuri, with the islands having spiritual, cultural, political and customary significance. This group of small islands has one of the most pristine coastlines in New Zealand, with no human-mediated impacts from cur...

Rhodoliths are recognised as providing critical ecosystem services in nearshore systems through habitat provision. We tested the influence of rhodolith hosts and habitat on the diversity and composition of sessile and motile invertebrates found associated with two species of rhodolith. Investigations of cryptofauna were undertaken at three beds wit...

A new genus in the order Sporolithales (Corallinophycidae, Rhodophyta), Roseapetra farriae gen. et sp. nov. is described, based on material from northern New Zealand. Previously placed in the genus Heydrichia on the basis of morpho-anatomical characters, phylogenetic analyses have shown that this northern New Zealand taxon is not resolved with eith...

Human activity is an important driver of ecological and evolutionary change on our planet. In particular, domestication and biological introductions have important and long-lasting effects on species’ genomic architecture and diversity. However, genome-wide analysis of independent domestication and introduction events within a single species has no...

The coralline algal genus Corallinapetra is currently monospecific, and was established on the species Corallinapetra novaezelandiae, known from a single collection from north‐eastern New Zealand. On the basis of multi‐gene phylogenetic analyses, Corallinapetra has been resolved apart from all currently recognized families and orders within the Cor...

Molecular studies have reported the co‐existence of two species of Agarophyton in New Zealand: the newly described A. transtasmanicum with an apparently restricted distribution to some sites in the North Island, and the more wide‐spread A. chilense. Here we compared the distribution, genetic diversity, and structure of both Agarophyton species thro...

The Gracilariaceae is a species-rich family, with a number of members having high commercial value as sources of agar. Members of this family are also known for their phenotypic plasticity and convergent morphologies, resulting in considerable taxonomic confusion. Over the past two decades, two species of Agarophyton (previously part of Gracilaria)...

Coralline algae (Corallinophycideae) are calcifying red algae that are foundation species in euphotic marine habitats globally. In recent years, corallines have received increasing attention due to their vulnerability to global climate change, in particular ocean acidification and warming, and because of the range of ecological functions that coral...

Gigartina species are very common and abundant on intertidal rocky shores in New Zealand but members of this genus and the family Gigartinaceae are still not fully documented. A well-known species, distributed as No. 164 of the Lindauer Nova-Zelandicae Exsiccatae, were labelled by Lindauer as Gigartina tuberculosa from material collected in Stewart...

Cryptic diversity is common in the red algae and is often discovered when comparing specimens from distant locations or different morphotypes of species with high phenotypic plasticity. The genus Lophurella includes seven species from the cold-temperate coasts of the southern hemisphere. L. periclados is the only species reported from Australia whe...

The tetrasporophytic ‘Trailliella’ stage of the red algal genus Bonnemaisonia is reported for the first time from the Southern Hemisphere. Here we describe a bloom of the tetrasporophyte of B. hamifera from the mouth of the Waikouaiti River, Karitāne, South Island, where it occurred as thousands of free-floating tufts up to 1 cm wide in shallow wat...

A new species of Dictyota (Dictyotales, Phaeophyceae), formerly identified as D. intermedia, is described from Manawatāwhi/Three Kings Islands. Morphological and anatomical features, in addition to molecular sequence data, of specimens collected from Manawatāwhi and Rangitāhua/Kermadec Islands were compared and enabled us to confirm that D. interme...

Macroalgae in mesophotic coral ecosystems are generally understudied compared to corals and fishes yet may be more abundant than coral-dominated reefs given their lower depth limits (> 200 m) and ability to grow over soft and hard bottom habitats. These assemblages are abundant and diverse globally, with changing species composition with increasing...

Despite recent evidence that has shown a close phylogenetic relationship between Callophycus (familia incertae sedis) and the monotypic genus Placentophora (previously regarded as a member of the family Solieriaceae), the phylogenetic relationships of these genera within the order Gigartinales have not been unequivocally established. Although the f...

Pleurostichidium falkenbergii is an obligate epiphyte on Xiphophora chondrophylla and is endemic to northern New Zealand. This monotypic genus is characterised by having dorsiventral and laterally compressed thalli with 20 pericentral cells and complete cortication, adventitious trichoblasts, spherical spermatangial branches formed from cortical ce...

Cryptic diversity has been often detected in the red algae when molecular assisted taxonomy has been applied. It is common in species with alleged wide distributions or high phenotypic plasticity. The red algal genus Lophurella includes seven species from the cold and temperate southern hemisphere. L. caespitosa is endemic to New Zealand. L. pericl...

The genus Streblocladia was described by early European collectors based on S. neglecta, a marine red alga from southern New Zealand currently treated as a taxonomic synonym of Streblocladia glomerulata. In New Zealand, Streblocladia includes two species and has always been considered distinct. To analyse the phylogenetic relationships of this genu...

Mitochondria and plastids are generally uniparentally inherited and have a conserved gene content over hundreds of millions of years, which makes them potentially useful phylogenetic markers. Organelle single gene-based trees have long been the basis for elucidating inter-species relationships that inform taxonomy. More recently, high-throughput ge...

Sarcothalia lanceata is a broad-bladed, New Zealand red alga. The tetrasporic life stage contains a lambda-carrageenan that has a strong potential for commercial utilisation. The male and female gametophytic life stages contain kappa-II carrageenan that also has commercial potential. However, fundamental information on the growth and variation in c...

A population of the kelp Ecklonia radiata (Laminariales) has been found in mesophotic conditions at c. 72–80 m depth on the shelf surrounding Macauley Island, Rangitahua, Kermadec Islands (30 13.3'S, 178 23.8'W), in northern New Zealand, c. 900 km northeast of New Zealand on the western margin of the South Pacific Subtropical Gyre. This species was...

The brown algal genus Zonaria (Dictyotales: Dictyotaceae) is widely distributed in temperate waters. Two species, Zonaria turneriana J.Agardh and Zonaria aureomarginata J.A. Phillips & W.A. Nelson have previously been recorded from mainland New Zealand, and a third species, Zonaria diesingiana, has been recorded from the Kermadec Islands. As part o...

A new epiphytic species, Jania sphaeroramosa sp. nov., is described from rocky reef intertidal zones around the coast of New Zealand and associated islands. This species forms round tufts on a range of hosts. Thalli display a unique three-dimensional growth form, built up with multiple layers of dichotomous fronds. The thalli are dichotomously bran...

A new species in the genus Prasionema (Prasiolales, Trebouxiophyceae) is described from Campbell Island, in the New Zealand subantarctic region, the first record of this genus in the southern hemisphere. Prasionema heeschiae sp. nov. is filamentous, uni- to predominantly biseriate, with disc-shaped cells, and an axial plastid with a central pyrenoi...

What is IPBES? IPBES—the Intergovernmental Platform on Biodiversity and Ecosystem Services—was established in 2012 to serve a role linking the science and knowledge about nature and nature’s benefits to people with policy and decision-making. IPBES has many expert groups, including one that focusses on Scenarios and Models of Biodiversity of Ecosy...

In the marine environment Species Distribution Models (SDMs) have been used in hundreds of papers for predicting the present and future geographic range and environmental niche of species. We have analyzed ways in which SDMs are being applied to marine species in order to recommend best practice in future studies. This systematic review was registe...

Rhodoliths of the South Pacific remain largely unstudied. Twenty two rhodolith-forming species from ten genera have been reported from the southern Pacific, although of these, only nine species in six genera have been confirmed as rhodolith records in the literature. There have been few ecological or distributional studies of rhodoliths in the sout...

Seaweed aquaculture beds (SABs) that support the production of seaweed and their diverse products, cover extensive coastal areas, especially in the Asian-Pacific region, and provide many ecosystem services such as nutrient removal and CO2 assimilation. The use of SABs in potential carbon dioxide (CO2) mitigation efforts has been proposed with comme...

The threat posed by ocean acidification (OA) to the diversity and productivity of New Zealand marine ecosystems is assessed in a synthesis of published trends and impacts. A 20-year time series in Subantarctic water, and a national coastal monitoring programme, provide insight into pH variability, and context for experimental design, modelling and...

The marine crustose brown algal genus Mesospora is poorly known despite its wide occurrence in tropical and warm temperate coastal areas. Taxonomic studies on Mesospora are largely dependent on the presence of reproductive structures due to its simple thallus morphology and vegetative anatomy. Increased sampling and the combination of molecular and...

Studies of New Zealand Kallymeniaceae have revealed a great deal of diversity, providing new perspectives on relationships within the family and necessitating the establishment of new genera. Based on rbcL, cytochrome c oxidase subunit 1 (COI), psbA sequence analyses and morphological observations, we reassessed the phylogenetic relationships of th...

Rhodophyta, or red algae, comprises a monophyletic lineage within Archaeplastida that includes glaucophyte algae and green algae plus land plants. Rhodophyta has a long fossil history with evidence of Bangia-like species in ca. 1.2 billion-year-old deposits. Red algal morphology varies from unicellular, filamentous, to multicellular thalloid forms,...

A new species of Predaea (Rhodophyta, Nemastomatales) was discovered from collections made in Fiordland, the southwestern region of the South Island, New Zealand (c. 458S). This is the southernmost record of the genus and the highest-latitude discovery of Predaea gametophytes in the world. Predaea rosa sp. nov. is described based on both anatomical...

Red algal parasites are diverse organisms that are unusual due to the fact that many are closely related to their hosts. Parasitism has developed many times within different red algal groups, but the full extent of parasite biodiversity is unknown, as parasites are easily overlooked due to their small size and often low abundance. Additionally, the...

Seascapes contain a mosaic of ecosystem types, including ‘small natural features’ that support a diverse fauna and flora, and provide ecosystem services disproportionate to their size. These include tropical coral reefs, seagrass meadows, rhodolith beds, kelp and mangrove forests as well as deep-sea coral reefs, sponge gardens and hydrothermal vent...

Several subspecies are defined within Codium fragile, including the invasive C. fragile ssp. fragile, first reported in New Zealand in 1973. An endemic subspecies, Codium fragile ssp. novae-zelandiae, is also found throughout New Zealand. The two subspecies exhibit morphological and molecular variation, although these have never been evaluated toge...

The red alga Chrysymenia saccata was first discussed by J.Agardh in 1876, and described in 1877. In subsequent publications there has been confusion about the type material, as well as the identity, and correct taxonomic placement of this species, currently referred to the genus Gloioderma. We consider the nomenclatural and taxonomic history of thi...

Rhodophyta, or red algae, comprises a monophyletic lineage within Archaeplastida that includes glaucophyte algae and green algae plus land plants. Rhodophyta has a long fossil history with evidence of Bangia-like species in ca. 1.2 billion-year-old deposits. Red algal morphology varies from unicellular, filamentous, to multicellular thalloid forms,...

Pterocladia lucida (Gelidiales), an important agar source in New Zealand, commonly occurs subtidally in Australia and New Zealand and is very variable in morphology. In the present study, the genetic diversity of P. lucida was investigated for 33 specimens collected in Australia and New Zealand. Phylogenetic analyses of mitochondrial cox1 and plast...

Recent collections from marine and freshwater locations have enabled the investigation of diversity of Prasiola in Japan. Sequence data from the rbc L and tuf A markers revealed the presence of three marine species and one freshwater species. Prasiola delicata was confirmed to occur on Daikokujima, Prasiola calophylla was found for the first time i...

Genetic diversity of native and introduced populations of Ulva pertusa (Ulvales, Chlorophyta) was examined using genetic markers of chloroplast, mitochondria and nuclear non-coding region sequences. In the preliminary investigations to genetically identify the species for further analyses, U. pertusa was found only from temperate coasts of the more...

In depth genetic comparisons of populations of Cutleria multifida (Tilopteridales, Phaeophyceae) collected from Europe, the northwestern Pacific Ocean, Australia and New Zealand using the DNA sequences of four gene regions (the mitochondrial cox2 and cox3 genes, the intergeneric spacer region adjacent to cox3, and the open reading frame) suggested...

is a New Zealand carrageenophyte with tetrasporophytic thalli that produce carrageenan very close to the idealised structure of lambda-carrageenan. As such there is interest in its potential for commercial utilisation. There is no information on the biology and ecology of natural populations of this species, but this knowledge is critical for deter...

When large volumes of macroalgae wash up on beaches, accumulate in coastal areas or within confined bays, there can be significant local impacts. Blooms of macroalgae are being reported throughout the world with increasing frequency in estuarine and coastal areas in both temperate and tropical regions. This review examines examples of nuisance accu...

Two red algal classes, the Florideophyceae (ca. 6,748 spp.) and Bangiophyceae (ca. 198 spp.) comprise 98% of red algal diversity in marine and freshwater habitats. These two classes form well-supported monophyletic groups in most phylogenetic analyses. Nonetheless, the inter-ordinal relationships remain largely unresolved, in particular in the larg...

Recent collections in northern New Zealand and New Caledonia revealed a single undescribed species of Platoma in each of these countries. Platoma novae-zealandiae sp. nov. is distinguished from its New Caledonian congener by its less foliose habit, subterete to flattened branches decreasing in width with increasing level of branching, distinctive p...

Nothogenia fastigiata has been reported to exhibit great morphological variability and has been considered to be widely distributed in the Southern Hemisphere. To test its current circumscription, sequences from type material of N. fastigiata and other species currently synonymized with it were compared to those from recent collections of this and...

The marine red algal family Liagoraceae sensu lato is shown to be polyphyletic based on analyses of a combined rbcL and psaA dataset and the pattern of carposporophyte development. Fifteen of eighteen genera analyzed formed a monophyletic lineage that included the genus Liagora. Nemalion did not cluster with Liagoraceae sensu stricto, and Nemaliace...

Coralline red algae from the New Zealand region were investigated in a study focused on documenting regional diversity. We present a multi-gene analysis using sequence data obtained for four genes (nSSU, psaA, psbA, rbcL) from 68 samples. The study revealed cryptic diversity at both genus and species levels, confirming and providing further evidenc...

The genus Hypnea has been known in New Zealand for a long time but identification to species level has been difficult as only fragmentary and sterile material has been available for study and thus the genus has remained poorly known. Recently large amounts of Hypnea were collected in northern New Zealand enabling DNA sequencing and the presence of...

Recent research voyages in the New Zealand region have resulted in new macroalgal specimens and underwater imagery from a range of deepwater habitats in coastal and offshore areas. In addition, targeted surveys have enabled the investigation of the biodiversity of specific island and shelf regions of New Zealand, and assemblages in biogenic habitat...

The Three Kings Islands are an uninhabited archipelago 57 km north of the North Island of New Zealand. Three new species of red algae were described from the Three Kings Islands: Perplexiramosus clintonii gen. et sp. nov., the first record of a member of the Furcellariaceae (Gigartinales) in the South Pacific Ocean, found growing exclusively on Sar...

An epiphytic bladed member of the Bangiales was found growing in Christchurch (South Island, New Zealand) Molecular sequence data and morphological comparisons revealed that the New Zealand specimens belong to the species Pyropia koreana (M. S. Hwang & I. K. Lee) M. S. Hwang, H. G. Choi, Y. S. Oh & I. K. Lee. This is the first record of Py. koreana...

An investigation of the red alga Grateloupia aucklandica from New Zealand subantarctic islands revealed that this species belongs in the genus Glaphyrosiphon. Phylogenetic analysis using rbcL data indicated that Grateloupia aucklandica, found on Auckland and Campbell Islands (50-52.5°S), was more closely related to Gl. chilensis, a species reported...

New Zealand foliose red algae belonging to the family Halymeniaceae were examined with a focus on species that have been placed in the genera Halymenia and Cryptonemia. Phylogenetic analyses of plastid-encoded rbcL and morphological observations were undertaken. Samples from northern New Zealand, referred to as Halymenia latifolia, were compared ge...

New Zealand foliose red algae belonging to the family Halymeniaceae were examined with a focus on species that have been placed in the genera Halymenia and Cryptonemia. Phylogenetic analyses of plastid-encoded rbcL and morphological observations were undertaken. Samples from northern New Zealand, referred to as Halymenia latifolia, were compared ge...

The nomenclatural history of the New Zealand members of the red algal order Gracilariales is summarized, including lectotypification of three species and the provision of a name, Curdiea furcata sp. nov., for an invalidly described species, currently known as Curdiea flabellata V.J. Chapm. This article is a contribution towards clarifying the taxon...

Rhodolith beds are recognised internationally as unique ecosystems, harbouring a high diversity and abundance of marine biota. Beds typically occur in environments of moderate exposure and coarse sandy sediments, in which individual rhodoliths are not moved away from the beds, and do not get buried by fine sediments. For the first time in New Zeala...

Colpomenia peregrina is an annual brown macroalga found in temperate waters worldwide. To understand population differentiation and to reconstruct pathways of colonization/introduction, we analyzed variation in two mitochondrial protein-coding genes, cytochrome c oxidase subunit III (cox3) and ATP synthase F0 subunit 6 (atp6), and cp RuBisCO spacer...

The macroalgal flora associated with rhodolith beds in the Bay of Islands, northeastern North Island, was investigated as part of the first detailed study of subtidal rhodoliths in New Zealand. The rhodolith beds differed in their physical characteristics and in the dominant rhodolith-forming species present, one bed with clear water and predominan...

A finely pinnately branched species of Grateloupia not seen previously in New Zealand was collected in Tauranga, New Zealand, growing on a tug boat. Molecular sequencing data (rbcL) revealed it to be Grateloupia subpectinata, a species first described from Japan, and also reported as native to Korea and China, and introduced to Britain, France, and...

Herbaria and natural history collections (NHC) are critical to the practice of taxonomy and have potential to serve as sources of data for biodiversity and conservation. They are the repositories of vital reference specimens, enabling species to be studied and their distribution in space and time to be documented and analysed, as well as enabling t...