Marine algal (seaweed) flora of Terceira Island, Azores

Background

As for many other Azorean islands, the macroalgal flora of Terceira (central group of the archipelago) is poorly known, the published information reflecting occasional collections of sporadic visitors to the island. In order to overcome this, and contribute to improve the knowledge of Azorean macroalgal flora at both local and regional scales, a thorough investigation was conducted and both collections and presence data recordings were undertaken at the littoral and sublittoral levels down to approximately 40 m around the island (total area of approximately 49 km2). This paper lists the taxonomic records and provides information on each species’ ecology and occurrence on the island’s littoral.

New information

A total of 418 specimens (including taxa identified only to genus level) belonging to 147 taxa of macroalgae, comprising 95 Rhodophyta, 33 Chlorophyta and 19 Ochrophyta (Phaeophyceae) are registered. Of these, 113 were identified to species level (73 Rhodophyta, 24 Chlorophyta and 16 Ochrophyta), encompassing 35 new records for the island (27 Rhodophyta, 6 Chlorophyta and 2 Ochrophyta). Most species are native including the Macaronesian endemisms (Codium elisabethiae O.C.Schmidt, Millerella tinerfensis (Seoane-Camba) S.M.Boo & J.M.Rico and Phyllophora gelidioides P.Crouan & H.Crouan ex Karsakoff), eight are introduced and 15 have uncertain origin.

Introduction

The macroalgal flora of the isolated mid-Atlantic Azores archipelago, as a whole, may be considered relatively rich when compared to that of other remote oceanic islands such as the Shetlands and Faroes in the colder North Atlantic, and Ascension and Tristan da Cunha in the Southern Atlantic (Neto et al. 2005; Tittley & Neto 2005; Wallenstein et al. 2009). With approximately 400 species (Freitas et al. 2019), the Azorean algal flora has been considered cosmopolitan, as it shares species with Macaronesia, North Africa, the Mediterranean Sea, Atlantic Europe and America (Tittley 2003; Tittley & Neto 2006; Wallenstein et al. 2009).

The published information, however, reflects data from only a few of the nine islands. Terceira, the second largest island of the central group and the third largest of the archipelago, is among the lesser studied ones. To overcome this and contribute to a better understanding of the seaweed flora of the Azores archipelago, a thorough investigation was conducted in the period between 2000 and 2014, mainly by the Island Aquatic Research Group of the Azorean Biodiversity Centre of the University of the Azores (https://ce3c.ciencias.ulisboa.pt/sub-team/island-aquatic-ecology). In these surveys, special attention was dedicated to the sheet-like and filamentous forms that are difficult to identify in the wild, the seasonal and fast growing annuals, and particularly to the small forms that are often short-lived and fast growing species, very difficult to identify without the aid of a microscope. This paper compiles physical, occurrence and survey data and is intended as a practical resource for biological studies (such as systematics, diversity and conservation, biological monitoring, climate change and ecology), and for academics, students, government, private organizations, and the general public.

Purpose

By listing the taxonomic records for Terceira and presenting general information for each taxon’s occurrence on the island’s littoral, this paper addresses several biodiversity shortfalls (see Hortal et al. 2015), namely the need to catalogue the Azorean macroalgae (Linnean shortfall) and improve the current information on their local and regional geographic distribution (Wallacean shortfall), as well as on species’ abundances and dynamics in space (Prestonian shortfall).

Default

Identification

Alternate Identifier
10.15468/3u2p9z
Alternate Identifier
b03dce75-cbc2-457b-8725-33885d766a05
Alternate Identifier
http://ipt.gbif.pt/ipt/resource?r=terceira_seaweed_flora
Publication Date
2020-07-31
Title
Marine algal (seaweed) flora of Terceira Island, Azores
Abstract

Background

As for many other Azorean islands, the macroalgal flora of Terceira (central group of the archipelago) is poorly known, the published information reflecting occasional collections of sporadic visitors to the island. In order to overcome this, and contribute to improve the knowledge of Azorean macroalgal flora at both local and regional scales, a thorough investigation was conducted and both collections and presence data recordings were undertaken at the littoral and sublittoral levels down to approximately 40 m around the island (total area of approximately 49 km2). This paper lists the taxonomic records and provides information on each species’ ecology and occurrence on the island’s littoral.

New information

A total of 418 specimens (including taxa identified only to genus level) belonging to 147 taxa of macroalgae, comprising 95 Rhodophyta, 33 Chlorophyta and 19 Ochrophyta (Phaeophyceae) are registered. Of these, 113 were identified to species level (73 Rhodophyta, 24 Chlorophyta and 16 Ochrophyta), encompassing 35 new records for the island (27 Rhodophyta, 6 Chlorophyta and 2 Ochrophyta). Most species are native including the Macaronesian endemisms (Codium elisabethiae O.C.Schmidt, Millerella tinerfensis (Seoane-Camba) S.M.Boo & J.M.Rico and Phyllophora gelidioides P.Crouan & H.Crouan ex Karsakoff), eight are introduced and 15 have uncertain origin.

Introduction

The macroalgal flora of the isolated mid-Atlantic Azores archipelago, as a whole, may be considered relatively rich when compared to that of other remote oceanic islands such as the Shetlands and Faroes in the colder North Atlantic, and Ascension and Tristan da Cunha in the Southern Atlantic (Neto et al. 2005; Tittley & Neto 2005; Wallenstein et al. 2009). With approximately 400 species (Freitas et al. 2019), the Azorean algal flora has been considered cosmopolitan, as it shares species with Macaronesia, North Africa, the Mediterranean Sea, Atlantic Europe and America (Tittley 2003; Tittley & Neto 2006; Wallenstein et al. 2009).

The published information, however, reflects data from only a few of the nine islands. Terceira, the second largest island of the central group and the third largest of the archipelago, is among the lesser studied ones. To overcome this and contribute to a better understanding of the seaweed flora of the Azores archipelago, a thorough investigation was conducted in the period between 2000 and 2014, mainly by the Island Aquatic Research Group of the Azorean Biodiversity Centre of the University of the Azores (https://ce3c.ciencias.ulisboa.pt/sub-team/island-aquatic-ecology). In these surveys, special attention was dedicated to the sheet-like and filamentous forms that are difficult to identify in the wild, the seasonal and fast growing annuals, and particularly to the small forms that are often short-lived and fast growing species, very difficult to identify without the aid of a microscope. This paper compiles physical, occurrence and survey data and is intended as a practical resource for biological studies (such as systematics, diversity and conservation, biological monitoring, climate change and ecology), and for academics, students, government, private organizations, and the general public.

Purpose

By listing the taxonomic records for Terceira and presenting general information for each taxon’s occurrence on the island’s littoral, this paper addresses several biodiversity shortfalls (see Hortal et al. 2015), namely the need to catalogue the Azorean macroalgae (Linnean shortfall) and improve the current information on their local and regional geographic distribution (Wallacean shortfall), as well as on species’ abundances and dynamics in space (Prestonian shortfall).

Dataset Language
ENGLISH
 
Dataset Creator
  Universidade dos Açores, Faculdade de Ciências e Tecnologia, Departamento de Biologia and Grupo de Investigação Aquática Insular, IBBC-GBA/cE3c - Ana Isabel Neto (Associate professor with aggregation; Macroalgae Curator at the AZB Herbarium Ruy Telles Palhinha )
Rua da Mãe de Deus, 13-A , Ponta Delgada , São Miguel, Açores , 9500-321 , PORTUGAL
http://ce3c.ciencias.ulisboa.pt/member/anaisabelneto
Dataset Creator
  Universidade dos Açores, Faculdade de Ciências e Tecnologia, Departamento de Biologia and Grupo de Investigação Aquática Insular, IBBC-GBA/cE3c - Afonso C. L. Prestes (Researcher )
Rua da Mãe de Deus, 13-A , Ponta Delgada , São Miguel, Açores , 9500-321 , PORTUGAL
https://ce3c.ciencias.ulisboa.pt/member/afonsoprestes
Dataset Creator
  Universidade dos Açores, Faculdade de Ciências Agrárias, CCMMG (Centro do Clima Meteorologia e Mudanças Globais), IITA-A (Instituto de Investigação e Tecnologias Agrárias e do Ambiente) - Nuno V. Álvaro (Researcher )
Campus de Angra do Heroísmo Rua Capitão João d’Ávlia – Pico da Urze , Angra dp Heroísmo , Terceira, Açores , 9700-042 , PORTUGAL
http://cita.angra.uac.pt/clima/equipa/ver.php?id=245
Dataset Creator
  * Universidade dos Açores, Faculdade de Ciências e Tecnologia, Departamento de Biologia - Roberto Resendes (Curator at the AZB-Herbarium Ruy Telles Palhinha )
Rua da Mãe de Deus, 13-A , Ponta Delgada , São Miguel, Açores , 9500-321 , PORTUGAL
Dataset Creator
  NA - Raul M. A. Neto (Collaborator )
PORTUGAL
Dataset Creator
  Ignacio Moreu (Researcher )
Rua da Mãe de Deus, 13-A , Ponta Delgada , São Miguel, Açores , 9500-321 , PORTUGAL
https://ce3c.ciencias.ulisboa.pt/member/Ignacio_Moreu_Badia
Metadata Provider
  Universidade dos Açores, Faculdade de Ciências e Tecnologia, Departamento de Biologia and Grupo de Investigação Aquática Insular, IBBC-GBA/cE3c - Ana Isabel Neto (Associate professor with aggregation; Macroalgae Curator at the AZB Herbarium Ruy Telles Palhinha )
Rua da Mãe de Deus, 13-A , Ponta Delgada , São Miguel, Açores , 9500-321 , PORTUGAL
http://ce3c.ciencias.ulisboa.pt/member/anaisabelneto
Metadata Provider
  Universidade dos Açores, Faculdade de Ciências e Tecnologia, Departamento de Biologia and Grupo de Investigação Aquática Insular, IBBC-GBA/cE3c - Ignacio Moreu (Researcher )
Rua da Mãe de Deus, 13-A , Ponta Delgada , São Miguel, Açores , 9500-321 , PORTUGAL
https://ce3c.ciencias.ulisboa.pt/member/Ignacio_Moreu_Badia
Associated Party
AUTHOR
  Universidade dos Açores, Faculdade de Ciências e Tecnologia, Departamento de Biologia and Grupo de Investigação Aquática Insular, IBBC-GBA/cE3c - Ana Isabel Neto (Associate professor with aggregation; Macroalgae Curator at the AZB Herbarium Ruy Telles Palhinha )
Rua da Mãe de Deus, 13-A , Ponta Delgada , São Miguel, Açores , 9500-321 , PORTUGAL
http://ce3c.ciencias.ulisboa.pt/member/anaisabelneto
Associated Party
AUTHOR
  Universidade dos Açores, Faculdade de Ciências e Tecnologia, Departamento de Biologia and Grupo de Investigação Aquática Insular, IBBC-GBA/cE3c - Ignacio Moreu (Researcher )
Rua da Mãe de Deus, 13-A , Ponta Delgada , São Miguel, Açores , 9500-321 , PORTUGAL
https://ce3c.ciencias.ulisboa.pt/member/Ignacio_Moreu_Badia
Dataset Contact
  Universidade dos Açores, Faculdade de Ciências e Tecnologia, Departamento de Biologia and Grupo de Investigação Aquática Insular, IBBC-GBA/cE3c - Ana Isabel Neto (Associate professor with aggregation; Macroalgae Curator at the AZB Herbarium Ruy Telles Palhinha )
Rua da Mãe de Deus, 13-A , Ponta Delgada , São Miguel, Açores , 9500-321 , PORTUGAL
http://ce3c.ciencias.ulisboa.pt/member/anaisabelneto
Keywords (N/A )
  • Rhodophyta
  • Terceira Island
  • introduced
  • Chlorophyta
  • native
  • Macroalgae
  • seaweeds
  • Ochrophyta
  • endemism
  • Azores
  • occurrence data.
  • uncertain
Keywords (GBIF Dataset Type Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_type.xml )
  • Samplingevent

Geographic Coverage

Geographic Description
Terceira Island, Azores, Macaronesia, Portugal (approximately 38°48′50″N, 27°23′25″W).

Bounding Box

West Bounding Coordinate
-27.389
East Bounding Coordinate
-27.033
North Bounding Coordinate
38.814
South Bounding Coordinate
38.627

Temporal Coverage

Range of Dates

Begin Date

2000

End Date

2014

Taxonomic Coverage

General Taxonomic Coverage
All macroalgae were identified to genus or species. In total, 147 taxa were identified belonging to 21 orders and 45 families, distributed by the phyla Rhodophyta (9 orders and 25 families), Chlorophyta (5 orders and 8 families) and Ochrophyta (7 orders and 12 families).

Taxonomic Classification

Taxonomic Rank Name
Phylum
Taxonomic Rank Value
Rhodophyta
Common Name
Red algae

Taxonomic Classification

Taxonomic Rank Name
Phylum
Taxonomic Rank Value
Chlorophyta
Common Name
Green algae

Taxonomic Classification

Taxonomic Rank Name
Phylum
Taxonomic Rank Value
Ochrophyta
Common Name
Brown algae

License Information

Intellectual Rights

This work is licensed under a

Creative Commons Attribution (CC-BY) 4.0 License

.

 
 
 

Projects

Projects

• ProjectSeaweeds of Terceira Island (Azores)

Title
Marine algal (seaweed) flora of Terceira Island, Azores

Personnel

Individual Name

Given Name
Afonso C. L.
Surname
Prestes
Role
CONTENT_PROVIDER

Personnel

Individual Name

Given Name
Albert
Surname
Cámara
Role
CONTENT_PROVIDER

Personnel

Individual Name

Given Name
Ana Isabel
Surname
Neto
User ID
0000-0003-0708-5636
Role
CONTENT_PROVIDER

Personnel

Individual Name

Given Name
Luís
Surname
Cabral
Role
CONTENT_PROVIDER

Personnel

Individual Name

Given Name
Mariana
Surname
Brito
Role
CONTENT_PROVIDER

Personnel

Individual Name

Given Name
Marisa
Surname
Toste
Role
CONTENT_PROVIDER

Personnel

Individual Name

Given Name
Marlene
Surname
Terra
Role
CONTENT_PROVIDER

Personnel

Individual Name

Given Name
Nuno
Surname
Álvaro
Role
CONTENT_PROVIDER

Personnel

Individual Name

Given Name
Rita
Surname
Patarra
Role
CONTENT_PROVIDER
Abstract
In order to improve the knowledge of Terceira Island’s macroalgal flora, extensive observations were made in the period between 2000 and 2014, encompassing both collections and presence data recordings, and covering the littoral and sublittoral levels down to approximately 40 m around the island (total area of approximately 49 km2). This paper lists the resulting taxonomic records and provides information on each species’ ecology and occurrence on the island’s littoral.
Funding

This study was mainly financed by the following projects/scientific expeditions:

• Campaign CAMAG-TER/2008, under the project “CAMAG/TER - Caracterização das massas de água costeira da Ilha Terceira”. 2008 - 2009. The Azores Regional Government;

• Project “ACORES-01-0145-FEDER-000072 - AZORES BIOPORTAL – PORBIOTA. Operational Program Azores 2020 (85% ERDF and 15% regional funds);

• Portuguese National Funds, through FCT – Fundação para a Ciência e a Tecnologia, within the projects UID/BIA/00329/2013, 2015 - 2018, and UID/BIA/00329/2019 and UID/BIA/00329/2020-2023;

• Portuguese Regional Funds, through DRCT – Direção Regional da Ciência e Tecnologia, within several projects, since 2013;

• CIRN/DB/UAc (Research Centre for Natural Resources, Universidade dos Açores, Departamento de Biologia);

• CIIMAR (Interdisciplinary Centre of Marine and Environmental Research, Porto, Portugal).

Study Area Description

Descriptor

Located along a WNW-trending strip and spreading over 500 km in the North Atlantic, roughly at 38°43′49″N 27°19′10″W, the Azores archipelago is composed by nine islands and several islets. The islands are surrounded by deep waters due to the absence of a continental shelf, and therefore have a restricted coastal extension, which is subjected to swell and surge most of the year. The tidal range is small (<2 m, see Instituto Hidrográfico 1981) and the shore geomorphology alternates between high cliffs and rocky cobble/boulder beaches (Borges 2004). The climate is temperate oceanic, with regular and abundant rainfall and high levels of relative humidity and persistent winds mainly during winter and autumn (Morton et al. 1998).

Terceira, located in the central group, roughly at 38°48′50″N, 27°23′25″W, 150 km northeast of São Miguel, is the third biggest island of the Azores archipelago. It has an elliptical form, 29 km long and 18 km wide, a maximum altitude of 1021 m at the summit of Serra de Santa Bárbara, and a total area of about 397 km2. The coastline has a total length of 112 km and is characterized by cliffs that vary from small to moderate heights, interrupted by small bays. Sandy beaches are limited to Praia da Vitória, located on the more protected eastern part of the island. The northern coast is more exposed and constantly submitted to the wave action (Gomes & Pinto 2004).

The intertidal and shallow subtidal rocky-shore communities of Terceira are dominated by macroalgae, similarly to those of the remaining Azorean islands (Neto et al. 2005). The frondose species Fucus spiralis Linnaeus, Ulva rigida C.Agardh and Gelidium microdon Kützing are often present at mid shore levels, growing interspaced with the small chthamalid barnacles. Slightly below this level, the lack of herbivores, resulting from the overexploitation of limpets (Martins et al. 2008, 2011, Faria et al. 2015), favours an almost homogeneous coverage of the shore by algal turfs. These are growth forms of either diminutive algae or diminutive forms of larger species that create a dense, compact mat 20-30 mm thick, either monospecific (mainly composed by Caulacanthus ustulatus (Mertens ex Turner) Kützing or Gymnogongrus spp.), or multispecific and composed by articulate calcareous algae (e.g. Ellisolandia elongata and Jania spp.) and/or soft algae (e.g. Centroceras clavulatum (C.Agardh) Montagne, Chondracanthus spp. and Laurencia spp.). Lower in the shore the erect, corticated macrophytes Ellisolandia elongata (J.Ellis & Solander) K.R.Hind & G.W.Saunders, Cystoseira spp. and Osmundea pinnatifida (Hudson) Stackhouse are commonly found, frequently epiphyting multispecific algal turfs. The shallow subtidal is mainly characterized by associations of two or three frondose macrophytes, predominantly the brown seaweeds Dictyota spp. and Zonaria tournefortii (J.V. Lamouroux) Montagne.

Design Description

Description
The algae referred to in this paper were sampled during field studies at littoral and sublittoral levels down to approximately 40 m on Terceira Island, covering an area of 49 Km2. Presence recordings and physical collections were made by walking over the shores or by scuba diving. The specimens collected were taken to the laboratory for standard procedures and the resulting vouchers were deposited at the AZB Herbarium Ruy Telles Palhinha, at the Faculty of Sciences and Technology of the University of the Azores.
 
 

Methods

Methods

• Method

Method Step

Description

In the laboratory the specimens were sorted and studied following standard procedures used in macroalgae identification.

Species identification was based on morphological and anatomical characters and reproductive structures. For small and simple thalli, this required the observation of the entire thallus by eye and/or using dissecting and compound microscopes. For larger and more complex algae, the investigation of the thallus anatomy required histological work to obtain longitudinal and transverse sections needed for the observation of cells, reproductive structures and other diagnosing characters.

Since the Azorean algal flora is composed of taxa from various geographical regions, floras and keys mainly from the Atlantic and Western Mediterranean were used in species identification (e.g. Schmidt 1931, Taylor 1967, 1978, Levring 1974, Dixon & Irvine 1977, Lawson & John 1982, Irvine 1983, Gayral & Cosson 1986, Fletcher 1987, Afonso-Carrillo & Sansón 1989, Burrows 1991, Boudouresque et al. 1992, Cabioc'h et al. 1992, Maggs & Hommersand 1993, Irvine & Chamberlain 1994, Brodie et al. 2007, Lloréns et al. 2012 and Rodríguez-Prieto et al. 2013).

For more critical and taxonomically difficult taxa, specimens were taken to the Natural History Museum (London) for comparison with collections there, or sent to specialists.

A reference collection was made for all specimens collected by giving them an herbarium code number and depositing them at the AZB Herbarium Ruy Telles Palhinha, University of Azores. Depending on the species and on planned further research, different types of collections were made, namely (i) liquid collections using 5% buffered formaldehyde seawater and then replacing it by the fixing agent Kew (Bridsen & Forman 1999); (ii) dried collections, either by pressing the algae (most species) as described by Gayral and Cosson (1986), or by letting them air dry (calcareous species); and (iii) silica collections for molecular studies.

Nomenclatural and taxonomic status used here follow Algaebase (Guiry & Guiry, 2020). The database was organized on FileMaker Pro.

Sampling

Study Extent

This study covers a relatively large area, approximately 49 Km2, encompassing littoral and sublittoral levels down to approximately 40 m around the Terceira island.

Sampling Description
Intertidal collections were made at low tide by walking over the shores. Subtidal collections were made by scuba diving around the area. Sampling encompassed both physical collections and species presence recordings. For the former, in each sampling location, collections were made manually by scraping one or two specimens of species found into labelled bags. Species recording data was gathered by registering all species present in the visited locations. Complementary data such as shore level (high, mid, low), orientation and type of substrate (bedrock, boulders, cobbles, mixed), habitat (tide pool, open rock, gully, crevice, cave) was also recorded.

qualityControl

Description
The collected taxa were investigated by trained taxonomists with the help of keys and floras. This involved morphological and anatomical examination by eye or under the dissecting and compound microscopes of an entire specimen or slide preparation. In difficult cases specimens were sent to experts for identification.
 
 

Not available