Welcome to the Guide to the shallow water Sponges of the North East Atlantic, constructed by

Rob van Soest, Bernard Picton and Christine Morrow.

The contents of this guide comprise a multimedia representation (text, "hot text", photos, drawings) of 337 species of sponges recorded from the coastal areas of the North East Atlantic between the low Arctic (northern Norway and Iceland) and southern Portugal, limited to depths of ca. 200 m. Furthermore the guide provides two different identification keys ("Text Key" and "IdentifyIt"), an "Introduction" module, an illustrated "Glossary", a reference module ("Literature") fully interlinked with the individual species, a distribution module ("MapIt") likewise fully interlinked with individual species, and a "Higher Taxa" module with information of families, orders and classes to which the North East Atlantic sponges belong. There is an "Index" with all taxa (species as well as higher taxa) listed and from which taxon records can be directly accessed with a mouse click.
As a bonus there is a "Who is who" module containing portraits and biographic data on sponge systematicians.


Sources for the information are manifold, but major sources were the Marine Conservation Society's Sponge I-V guides, with contributing authors Bernard Picton, Graham Ackers, Shirley Stone, Christine Morrow, and David Moss. Many of the live colour photos reproduced here were obtained through the gracious cooperation of the Society and in particular of Bernard Picton. Many of the spicule drawings reproduced here were made by Christine Morrow. Several of the descriptive texts - though edited for uniformity sake - were taken more or less literally from Sponge V. The Marine Conservation Society kindly granted the right to use these illustrations here. A further major source is the old guide on sponges in the "Tierwelt Nord- und Ostsee" series by Walther Arndt (1935). An even older source - used with prudence, but very useful because of its superior illustrations - is Bowerbank's four volume (1864-1882) monograph on the British sponges.
For the definitions of Higher Taxa a major source has been John Hooper's internet Sponge Guide.

What you need to know about sponges

Sponges are sessile Metazoans with a low grade of organization: only two coherent tissue layers exist, viz. a skin-like tissue called "pinacoderm" lining the outside and all inside canals, and a layer of flagellated cells called "choanocytes" lining the inside of chambers. Many free cells roam around in the areas between the canals and the chambers. Food and oxygen are obtained by generating a water current through the body. The water enters the body through myriads of small pores and is led through canals to the choanocyte chambers. The water leaves the body through exhalant canals leading towards larger central openings called "oscules". Sponge individuals may have one or more oscules. Sponges derive support from and maintain their form by a skeleton built from discrete small needles of silica or limestone called "spicules"or alternatively from a system of fibres of a horn-like substance called "spongin". Classification and identification of most sponges is based on details of their skeletons.

How to identify sponges ?

Very few, if any, sponges have a constant form, colour and size. Macroscopic details are a very unreliable data set for identification, although experienced spongologists usually are able to recognize their species on sight/touch/smell. Taxonomy and classification are based on very small details of the skeleton and thus for a reliable identification it is absolutely imperative to make microscopic slide preparations of the skeleton and the spicules. With some experience, routine identifications may be made from easy-to-do crude sections (one parallel to the surface, one perpendicular to it), dried and mounted in Canada balsam. In many cases it is sufficient to make an even simpler spicule preparation by dissolving the organic parts in concentrated household bleach. For a full treatment of preparation procedures see "Introduction" module, topics "Spicule preparations" and "Thick sections". One needs a high magnification (100-400 x) to examine the skeleton and/or the spicules in sufficient detail for identification. Consult the "Glossary" module for explanations of the various terms for skeletal details. Consult the "Higher Taxa" module for information and characterization of classes, orders, families and genera.

Species information

All 337 species are described in a fixed order. They are first characterized in a short overview, and then described in taxonomic details following the sequence: Colour / Shape, size, surface and consistency / Spicules / Skeleton / Ecology / Distribution / Etymology / Type specimen information / Remarks.
For many type specimens the museum collection where they are kept is indicated; sometimes no information is available at present. The type specimen information is often accompanied by a "MCS voucher" number, referring to specimens of the collection of the Belfast Museum (BELUM) of which live pictures are taken up in this guide. For consultation of these specimens one is referred to Bernard Picton.
All blue text is "hot", i.e. clicking on a word leads you to information on the searched-for item. In addition, words and names may be preceded by a camera symbol and clicking on this will show a picture illustrating the word or the name.
For each species synonyms and literature records are provided as comprehensively as possible. All literature mentioned in the synonymy is fully cited and linked to the "Literature" module.
For each species a full classification to family, order and class is provided in the Taxonomy field. Taxon names are "hot" and linked to the "Higher Taxa"module. Finally there is a list of all pictures available for the species in the Multimedia field; these can be individually accessed by clicking on the camera symbol.
By clicking the "Contents" symbol below the window you get access to an alphabetical list of all species treated in the guide and clicking on a name will get you there.

Distribution information

The distribution records for each species have been entered in an - admittedly coarse - grid system laid over a map of the North Atlantic Ocean to provide a one-glance overview of the species distribution. Information of various species may be compared and occurrence of all species in individual geographical localities (grid squares) may be "found". For further possible applications, please consult the "Help" menu.
By clicking the arrow next to the "Examine" field symbol above the window you get access to an alphabetical list of all species treated in the guide and clicking on a name will get you to the distribution map.

Higher Taxa information

The "Higher Taxa" module contains definitions and contents of all classes, subclasses, orders and families of sponges represented in the guide. Family records in addition contain definitions of all genera belonging to them as far as represented in the area, with a list of all species treated in this guide, as well as a list of species occurring in the area but in deeper water. The latter addition is made to point out obvious alternatives if a collected specimen does not seem to be represented in the "Species" module.
By clicking the "Contents" symbol below the window you get access to an alphabetical list of all higher taxa treated in the guide and clicking on a name will get you there.


More than 300 terms used in the descriptions of sponges are defined and in most cases illustrated.
By clicking the "Contents" symbol below the window you get access to an alphabetical list of all terms defined in the guide and clicking on a name will get you there.


Over 530 full literature references are provided in an alphabetical order. All references are linked to the relevant species in the"Species" module. The "Key words" field for each reference lists all taxa to which the literature reference is linked.
By clicking the "Contents" symbol below the window you get access to an alphabetical list of all references treated in the guide and clicking on a name will get you there.

Text Key

Traditional keying out of species is possible with the "Text Key". Up to four choices can be made each time a step in the key has been made (by clicking on the entry of choice). Many steps have been illustrated with pictures of key characters. The choice for a species will lead directly to the "Species" module, so the choice can be evaluated by comparing the description of the species with your specimen. Please consult the "Help" menu for many additional useful tools.


This is a "matrix"-type key, which compares the choice of characters and states you make on the basis of your specimen with the scores made for all the species. The species with the highest number of "hits" is the most likely choice. Different levels of entry are possible: if you are not sure of the class to which your specimen belongs you may try to identify this first (choose the "Classes" file from the "Phylum Porifera" folder in the Identify files folder). Once you have established which class your specimen belongs to you can then either directly determine your species (if your specimen belongs to the class Calcarea), or you then proceed to identify which order your specimen belongs to (if your specimen belongs to the Demospongiae). Once you have determined which order your Demosponge belongs to, you then click and "Go" to the IdentifyIt file of the order concerned. Characters and states can be simply clicked and one may get scores on likely identity with each step. Obviously, accuracy of the scores improves with a growing number of clicked states, but in theory a single click may get you the correct answer.


Consult this module for an array of subjects concerning sponges, from "Anatomy" to "Pharmaceutical compounds", each illustrated by an instructive image.
By clicking the "Contents" symbol below the window you get access to an alphabetical list of all topics treated in the introduction and clicking on a name will get you there.

Who is who

For those not belonging to the inner circles of sponge systematics it may be useful to find some biographic information on and a portrait - if available - of some of the heroes of this discipline. You will find a regrettably not comprehensive array of persons - treated not always exhaustively - who feature in the literature on sponges. Apologies to those of you who are not included in this illustrous series. Reasons may be trivial (e.g. we did not have a portrait of you other than in bathing suite or otherwise unsuitable for presentation), or intentional: you need to profile yourself more, we can't include each passer-by. It would be great to have a more comprehensive and better researched series of biographic descriptions of spongologists covering other disciplines than systematics.

Text: Rob van Soest