| Struvea | |
|---|---|
 | |
Scientific classification  | |
| Clade: | Viridiplantae |
| Division: | Chlorophyta |
| Class: | UTC clade |
| Order: | Cladophorales |
| Family: | Boodleaceae |
| Genus: | Struvea Sonder |
| Type species | |
| Struvea plumosa | |
| Species | |
Struvea is a genus of green macroalgae (or seaweed) in the family Boodleaceae. [1]
This genus was founded by Otto Wilhelm Sonder in 1845 and was named in honor of the Russian ambassador H. de Struve. [2] [3] Initially, the genus name was in conflict with Struvea Reichenbach, a heterotypic synonym of Torreya Arnott but P.C. Silva formally conserved Struvea Sonder in 1952 to prevent further taxonomic problems. [4] Currently, there is only four confirmed species for this genus. [1] This low species number was due to the segregation of Phyllodictyon from Struvea sensu lato based on differences in cell division processes [3] and later on supported by molecular data. [5] [6] [7] The Struvea plumosa sample collected by Ludwig Preiss from western Australia was described by Sonder and now serves as the holotype species for this genus. [2] [3] The voucher specimen for the type species is housed at the Royal Botanic Gardens Melbourne (MEL). [3] [8]
The thallus of Struvea is composed of a single to numerous (clumped) blades borne from a monosiphonous or aseptate stipe (i.e., stipitate in nature); moreover, the blades form a stellate or criss-cross network of 2–3 ranks of distichously-arranged pinnae (laterals) lying on one plane. [1] [3] Members of this genus exhibit one of the four major types of cytokinesis within the order Cladophorales [5] —segregative cellular division (SCD)—wherein the cytoplasm of a mother cell divides simultaneously into several independent cytoplasms that would later on produce cell walls and become daughter cells. [1] [3] [9] Differences between the type of cell division process has been used to delineate the members of Cladophorales, most notably the delineation between Struvea and Phyllodictyon—the latter of which exhibits centripetal invagination by a primordial septum (CI). [3] In terms of its cellular ultrastructure, the cell walls of Struvea are composed of crystalline inclusions forming single crystals that are broad, prismatic, and hexagonal, diamond, needle-shaped, or triangular in shape. [10] [11] Chloroplasts are also reticulate or net-like with numerous pyrenoids. [8]
Struvea are widely distributed in the tropics and subtropics, mainly Australia and the tropical Western Pacific. [1] Struvea elegans [12] is the most widely distributed species encompassing the Caribbean islands, [13] [14] [15] [16] Oman, [17] and Fiji. [18] Meanwhile, S. plumosa and S. thoracica are only found in Oceania. [3] [10] [19] [20] Lastly, S. okamurae seems to be restricted within the tropical Western Pacific [7] [21] [22] with Micronesia as the limit of its westernmost range. [23] However, this distribution data on Struvea could just be an artefact of poor taxon sampling.
Members of this genus are found on the intertidal zone down to mesophotic depths. [1] Struvea plumosa inhabit limestone areas of the intertidal zone down to 33 meters deep. [3] [8] S. elegans are only restricted to mesophotic depths. [3] S. okamurae is epilithic and found between 4–6 meters in depth. [7] Lastly, S. thoracica thrive in subtidal channels and/or reef flats of about 15–18 m in depth with substrate primarily composed of shell fragments and coral debris. [20]
Unfortunately, research on the life history of this genus is centered around its growth (SCD) rather than reproduction. However, being a member of family Boodleaceae the general cycle is believed to be diplontic and presence of zoospores have been observed. [1]
Due to its unknown life cycle, relatively few representative species, [1] and its tendency to inhabit subtidal areas [3] [7] [8] [20] —this genus is not harvested from the wild and there is no known culture technology.
Most chemistry research work on this genus is mainly centered around the calcium oxalate crystals present within the cell walls of the blades. [10] [11] Out of the four species, S. elegans does not possess any crystals while S. plumosa has diamond, triangular or pentagonal-shaped crystals and S. thoracica has needle-shaped ones. [11]
Due to a lack of general interest and use, there is currently no utilization and management strategy for the members of this genus. [24]
Chlorophyta is a division of green algae informally called chlorophytes.
The Ulvophyceae or ulvophytes are a class of green algae, distinguished mainly on the basis of ultrastructural morphology, life cycle and molecular phylogenetic data. The sea lettuce, Ulva, belongs here. Other well-known members include Caulerpa, Codium, Acetabularia, Cladophora, Trentepohlia and Monostroma.
Acetabularia is a genus of green algae in the family Polyphysaceae. Typically found in subtropical waters, Acetabularia is a single-celled organism, but gigantic in size and complex in form, making it an excellent model organism for studying cell biology. In form, the mature Acetabularia resembles the round leaves of a nasturtium, is 4 to 10 centimetres tall and has three anatomical parts: a bottom rhizoid that resembles a set of short roots; a long stalk in the middle; and a top umbrella of branches that may fuse into a cap. Unlike other giant unicellular organisms, which are multinucleate, members of this genus possess a single nucleus located in the rhizoid, which allows the cell to regenerate completely if its cap is removed. The caps of two Acetabularia may also be exchanged, even from two different species. In addition, if a piece of the stem is removed, with no access to the nucleus in the rhizoid, this isolated stem piece will also grow a new cap.
Caulerpa is a genus of seaweeds in the family Caulerpaceae. They are unusual because they consist of only one cell with many nuclei, making them among the biggest single cells in the world.
Halimeda is a genus of green macroalgae. The algal body (thallus) is composed of calcified green segments. Calcium carbonate is deposited in its tissues, making it inedible to most herbivores. However one species, Halimeda tuna, was described as pleasant to eat with oil, vinegar, and salt.
Codium is a genus of edible green macroalgae under the order Bryopsidales. The genus name is derived from a Greek word that pertains to the soft texture of its thallus. One of the foremost experts on Codium taxonomy was Paul Claude Silva at the University of California, Berkeley. Silva was able to describe 36 species for the genus, and in honor of his work on Codium, the species C. silvae was named after the late professor.
Udoteaceae is a family of green algae, in the order Bryopsidales.
Asterococcus is a genus of green algae in the order Chlamydomonadales. It is planktonic in freshwater ponds and lakes, or benthic within mires and swamps. It is a common and widespread genus, but is rarely abundant.
Bracteacoccus is a genus of green algae, the sole genus of the family Bracteacoccaceae. It is a terrestrial alga commonly found in soils, from the tropics to the poles.
Bryopsis, often referred to a hair algae, is a genus of marine green algae in the family Bryopsidaceae. Species in the genus are macroscopic, siphonous marine green algae that are made up of units of single tubular filaments. They can form dense tufts up to 40 cm in height. Each cell is made of up an erect thallus that is often branched into pinnules. Approximately 60 species have been identified in this genus since its initial discovery in 1809. The ecological success of Bryopsis has also been attributed to its associations with endophytic bacteria that reside in the cytoplasm of their cells.
Chaetomorpha is a genus of green algae in the family Cladophoraceae. Members of this genus may be referred to by the common name sea emerald.
Mychonastes is a genus of green algae, specifically of the Chlorophyceae. It is the sole genus of the family Mychonastaceae.
Pseudomuriella is a genus of green algae, specifically of the class Chlorophyceae. It is the sole genus of the family Pseudomuriellaceae. It is a terrestrial alga that inhabits soils.
Rhipiliopsis is a genus of green algae in the family Rhipiliaceae. Johnson-sea-linkia is a synonym.
Siphonocladus is a small genus of green algae in the family Siphonocladaceae. The algal body (thallus) is composed of long, club-shaped cells that divide by segregative cell division, followed by the formation of branches that break through the mother cell.
Udotea is a genus of green algae in the family Udoteaceae.
Valonia is a genus of green algae in the Valoniaceae family. The genus Ventricaria is now regarded as a synonym of Valonia.
Claudea is a marine red alga genus.
Batrachospermaceae is a family of fresh water red algae (Rhodophyta). Genera within the Batrachospermaceae generally have a "Lemanea-type" life history with carpospores germinating to produce chantransia. Sporophyte phase with meiosis occurs in an apical cell to produce the gametophyte stage. Pit connections have two pit plug cap layers with the other layer enlarged. This family of freshwater red algae is uniaxial, meaning each filament with a single apical cell. The genera included within Batrachospermaceae are listed in the table below.
Dictyota is a genus of brown seaweed in the family Dictyotaceae. Species are predominantly found in tropical and subtropical seas, and are known to contain numerous chemicals (diterpenes) which have potential medicinal value. As at the end of 2017, some 237 different diterpenes had been identified from across the genus.