Frequently Asked Questions

How are images in the Sponge Guide arranged?

Every image in the Sponge Guide is grouped by the scientific name and a set of physical characteristics.  The physical characteristics used are:

  • color
  • morphology (shape)
  • consistency (texture or feel)

Note that a single sponge may have multiple colors and a single species can exhibit different morphologies.

The physical characteristics for both the species and the specific photograph are listed on the corresponding Species information page or Image Attributes page.

How can I search for an image of a sponge?

By clicking on the "Find a Sponge!" tab on the right, you will see search boxes that allow you to search by either physical characteristics or by typing in a genus or species name into the text box.

For a more detailed search, click on Search at the top menu.  The search box over the species list will search not only the names and characteristics, but also the species notes and author list.  Go ahead and try it!


How did you determine the species name for each sponge that was photographed?

Every sponge photographed was examined by Prof. Sven Zea of the Universidad Nacional de Colombia.

Species names were determined from the physical characteristics of the sponge and by inspecting the skeleton under the microscope. This may include the three-dimensional arrangement of the organic fibers and the spicules, microscopic skeletal elements that are made of silica or calcium carbonate. To confirm the identity of each species, spicules and fibers were directly examined for at least one individual.

  • To isolate spicules, a small (2x2x2 mm) piece of sponge tissue was digested in household bleach contained in a well of a 24-well tissue plate. After 10-20 min, a few drops of the suspension were placed on a microscope slide, covered with a cover slip, and observed under the compound microscope.
  • Tissue cross- and tangential sections were cut as thin as possible with a scalpel or a razor blade, placed on a microscope slide, and allowed to dry on a warm hot plate. Once dry, pieces of nylon fishing line were placed on the sides of sections to serve as a support for a cover-slip and mounting medium (Permount, Canada Balsam) was added in drops over the sections, followed by a cover slip that was squeezed over the nylon sections with a weight (iron nut, lead weight). More mounting medium was then added to fill any gaps, and the slide was kept horizontal for days to weeks until the medium solidified; then, the edges of the cover slip were painted with nail polish to prevent the formation of bubbles.
  • Permanent spicule mounts were made in the lab by digesting overnight fragments of the sponge in 6-10 mL household bleach in a 50-100 mL flask and placed on a rotatory shaker. Suspensions were then transferred to a round-bottom centrifuge tube, centrifuged at 1500 rpm for10 min, washed in DI water three times, then centrifuged for 2-3 min in 2 mL 96 % ethanol, followed by 100 % ethanol. A few drops of the suspension were placed onto a microscope slide and allowed to evaporate, then 3 drops of mounting medium and a 22 x 40 mm cover slip were gently squeezed over the slide.
  • Spicules and tissue sections were examined, measured, and photographed using a camera mounted on a microscope.

Taxonomic references were used and are presented for each identified species.

A complete list of references used can be found here.


What other type of information is in the Sponge Guide?

In addition to names and characteristics of sponges, we have also cataloged:

  • location of each sponge
  • habitat where it was found (mangrove/coastal lagoon, rocky shore/shallow reef, and deep reef )
  • specific notes on an image or species name
  • composite images of spicules and tissue sections and detailed descriptions including ecological and taxonomic notes have been added for many species.

Where were the images taken?

Most images in the Sponge Guide are from coral reefs around the Bahamas Islands, but images and species from other areas of the Caribbean (Florida, Lesser Antilles, Colombia, Panama, Belize) are being added. Site names are provided for each image.


Why are there question marks (?) after some names?

While our best attempt has been made to identify each image, the exact scientific classification of some images is unclear, and these are denoted with a "?", either at the genus or species-level. We often use nick-names for these to help identify them for future studies.


Can I use an image in a presentation or lecture?

Yes!  Images are free to use for educational and instructional purposes.  Photo credits are provided on each image, and we ask that you reference the photographer and

Images cannot be used for commercial purposes.  Anyone who would like to use images for commercial uses or in a publication should contact


How can I reference the Sponge Guide?

Data from the sponge guide may be useful in your research and you are welcome to use it.  You can reference the Sponge Guide as:

Zea, S., Henkel, T.P., and Pawlik, J.R. 2014.  The Sponge Guide: a picture guide to Caribbean sponges.  3rd Edition. Available online at  Accessed on: 2017-02-25