Overview

Comprehensive Description

Description

 Growth form irregular, massive; usually less than 10 cm in diameter, sometimes up to 15–20 cm in diameter and 2–3 cm in height. Colour in vivo (generally also preserved specimens) light grey to white; several, slightly perceptible, tone dominances are possible (light green to light brown). Consistency soft and fragile. Surface, shared by all species of the genus, as an irregular network of dense collagen fibres, sometimes with mineral debris. Inhalant apertures 80–120 µm in diameter. Oscules scattered (2–4 mm in diameter). Light collagen amount (fibrous reticulate) in the mesohyl. Flagellate chambers large. Skeleton reticulate, with irregular meshes (300–600 µm), and extremely fragile because of scanty spongin and extreme abundance of mineral granulation. Primary and secondary fibres (40–200 µm) not distinguishable or hierarchically organized. 
Creative Commons Attribution 3.0 (CC BY 3.0)

© Renata Manconi, Barbara Cadeddu, Fabio Ledda, Roberto Pronzato

Source: ZooKeys

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Description

 Dysidea fragilis can be irregularly encrusting or massive and lobe-shaped. Encrusting forms may be up to 50 cm in diameter and 0.75 cm thick. Massive forms can be up to 30 cm in diameter. This species can vary in colour from brownish, greenish, greyish-white or reddish brown. The surface is covered in small conical projections (conuli) 1.5 mm in height and 2-2.5 mm diameter at the base. These conical projections are often lighter in colour. The exhalent openings (oscula) are scattered across the surface, can be slightly raised and vary in size from 2 to 5 mm in width. There are no spicules present and the skeleton is composed of spongin fibres making the consistency of Dysidea fragilis very elastic.Dysidea fragilis has a distinctive smell and may be sandy in colour where sand dominates the substrata. Interestingly, larger specimens may be found in tidal, rocky esturanine areas, and specimens in northern waters tend to be smaller in size. The skeleton of this species is often partially or completely obscured by sand grains, spicules of other sponges, diatom valves, formainifera and other hard materials. Such materials may be incorporated in within the skeleton (Hayward & Ryland, 1995).  

The barnacle Acasta spongites forms a specific association with Dysidea fragilis (Uriz et al., 1992). Dysidea fragilis may be mistaken for the very polymorphic Ulosa digitata, however, unlike Dysidea fragilis, Ulosa digitata has styles coring into its fibres (only visible under a microcope). Dysidea pallescens is a Mediterranean species also similar to Dysidea fragilis. Dysidea pallescens has is pink-purple in colouration with larger oscula and occurs in Lough Hyne, although may be found in other UK areas (Ackers et al., 1992).

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

©  The Marine Biological Association of the United Kingdom

Source: Marine Life Information Network

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Description

This sponge is usually whitish or grey in colour but can also be brown. In cases where sand grains predominate over organic matter the sponge can assume the colour of sand. It may be thinly encrusting or cushion to massive lobose in form. It is usually less than 15cm across, but can be greater than this in tidal, rocky estuaries. The surface is conulate, because of spongin fibres lifting the surface layer. The projections are sometimes lighter in colour than the main surface. This species may be confused with Dysidea pallescens which is pink-purple in colour with relatively larger oscules.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© National Museums Northern Ireland and its licensors

Source: Encyclopedia of Marine Life of Britain and Ireland

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Distribution

This species has been widely reported, but appears to be restricted to the Atlantic coasts of Europe, with some possible sightings in the Western Mediterranean.
Creative Commons Attribution 3.0 (CC BY 3.0)

© WoRMS for SMEBD

Source: World Register of Marine Species

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

A common species throughout the British Isles.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© National Museums Northern Ireland and its licensors

Source: Encyclopedia of Marine Life of Britain and Ireland

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Ecology

Habitat

Depth range based on 391 specimens in 1 taxon.
Water temperature and chemistry ranges based on 68 samples.

Environmental ranges
  Depth range (m): 0 - 140
  Temperature range (°C): 9.788 - 27.228
  Nitrate (umol/L): 0.236 - 9.794
  Salinity (PPS): 34.633 - 37.656
  Oxygen (ml/l): 4.352 - 6.375
  Phosphate (umol/l): 0.095 - 0.585
  Silicate (umol/l): 1.232 - 3.727

Graphical representation

Depth range (m): 0 - 140

Temperature range (°C): 9.788 - 27.228

Nitrate (umol/L): 0.236 - 9.794

Salinity (PPS): 34.633 - 37.656

Oxygen (ml/l): 4.352 - 6.375

Phosphate (umol/l): 0.095 - 0.585

Silicate (umol/l): 1.232 - 3.727
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

 Dysidea fragilis is a cryptic species and can be found on the lower shore and sublittoral. It lives in rock crevices, on stones, shell and gravel. It has also been found embedded in muddy sand.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

©  The Marine Biological Association of the United Kingdom

Source: Marine Life Information Network

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

An almost ubiquitous species under boulders on the low shore and on hard substrata in the sublittoral.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© National Museums Northern Ireland and its licensors

Source: Encyclopedia of Marine Life of Britain and Ireland

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!