This freshwater sponge (Spongilla sp.) was found encrusting a submerged tree branch near the shoreline of a small lake in Maine.  Note the small oval arthropods living on the surface of the sponge near the middle of the photo.

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I recently returned from a short vacation to New Hampshire/ Maine to see family and stomp the formative grounds (and waters) of my youth. While paddling around the small lake that I spent my summers, I found an abundance of this freshwater sponge (Spongilla sp.) growing submerged near the shoreline.  Growing on rocks it has a flat, encrusting morphology. On submerged branches it forms lumpy encrustations. And on shallow muddy bottoms it sends up skinny tendrils. The tissue is colored bright green due to a symbiotic association with algae. While you might find yourself thinking “freshwater sponge? really?”,  these sponges can be found across most of North America from Alaska south to Florida in relatively still freshwater lakes and ponds.  As a testament to their adaptability, this sponge can ‘degenerate’ into a dormant state, forming tiny cysts called gemmules.  These gemmules act as ‘seeds’ when favorable conditions return. The sponges reproduce sexually in the summertime and release free swimming larvae. Next time you find yourself at a lake, take a closer look at what you might otherwise think is just some lumpy ‘algae’…

The brain coral (Diploria clivosa) colony pictured above featured several areas ranging in size from 3-6 cm that exhibited very unusual cauliflower-like tissue expansion with warty protuberances.  The photo was taken offshore of South Beach, Miami, Florida.

Pictured above is the normal ‘meandroid’ growth form for the brain coral Diploria clivosa.  The tissue is relatively compact against the skeleton and  the tentacles are visible along the inner walls of the grooves.

A toothsome ‘sand diver’ lizardfish Synodus intermedius waits patiently for a smaller fish to come a little bit closer…

On Tuesday morning, our newest team member Graham and I made a shore dive just underneath the flight path of the Fort Lauderdale International Airport (FLL).  I’d read that there was some decent shore diving in the area, but I have very little experience in this neck of the woods. 95% of all my dives in Florida have been in the Keys…  It was a nice change of pace, although if you go yourself, don’t expect to see the level of diversity and coral coverage you might find further south or offshore.

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Success!  The Quest is complete.

For the third dive we had a definitive lead on where we’d find the Corynactis viridis.  My friend Laurent Foure is the curator of the public aquarium in Cap d’Agde; about 2.5 hours westward along the coast of the  Mediterranean. Laurant is an avid diver, and is very familiar with the marine environment nearby his aquarium.  He was able to connect us with a dive operator who could take us by boat to a dive spot inhabited by Corynactis viridis…

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Not your average Aiptasia… this Aiptasia mutabilis is the largest and most beautiful Aiptasia anemone I’ve ever seen… This one is about 10cm in diameter.

For the second dive on the ‘Corynactis Quest’ we moved 8 km east towards Marseille to a small and picturesque harbor village called Redonne…

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Echinaster sepositus sea star with Parazoanthus axinellae zoanthids.

From June 1-9 I was in France on a a two-fold mission.  The first half of the trip was spent in the south of France in Marseille and the surrounding area.  I stayed with my good friend Yvan Perez,  a professor at the Institute of Mediterranean Ecology and Paleo-Ecology at the University of Provence in Marseille. Yvan acted as my dive guide and translator as we searched along the coast for the temperate Eastern Atlantic/Mediterranean corallimorph Corynactis viridis.

The second half of the trip was spent in Strasbourg in the Alsace region of France near the German border where I gave a lecture on the Caribbean corallimorph species at the annual convention of Recif France, which is the society of French reef aquarists. Over the next couple of weeks I will be posting a series of articles on this trip, specifically the quest for Corynactis viridis…

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This lettuce sea slug (Elysia crispata) was cruising over a few Discosoma sanctithomae and D. neglecta polyps on its way to a patch of Bryopsis sp. algae in one of the holding tubs in the Morphologic Lab. It measures approx. 3cm in length.

The lettuce sea slug (Elysia crispata) is not a true nudibranch, as it is often referred,  but a ‘sacoglossan sea slug’.  Sacoglossans feed by sucking out the chlorophyll contents of algae, and then incorporate that chlorophyll into their own tissues.  Thus the slugs themselves become ‘solar powered’.

Elysia crispata are native across the Caribbean and prefer to feed on Caulerpa species algae like C. verticillata and C. sertularioides.  In an aquarium, when deprived of these preferred species, they will consume the pest hair algae Brysopsis sp. that most other herbivores avoid.