Tuesday, December 23, 2014

Species List: La Balsa Park, Mooloolah River, Mooloolaba, Sunshine Coast, 20-12-2014

16 species sighted at La Balsa Park, Mooloolah River, Mooloolaba, Sunshine Coast.

Julie, Terry and David on this 115 minute single shore-entry dive in depths to 6.6m. 25C water temp and 5m viz.

An early morning dive. We are out of our dry suits now. A remarkable dive in that we found three specimens that we have decided to call sp.'s because we have not been able to match them sufficiently to existing species.

The small Siphopteron sp. 1 is a an exquisite headshield slug. At 2mm we have considered the possibility it may be a juvenile of Siphopteron tigrinum but some features are not similar so we will leave it separated at present.

We think there are a number of cryptic species currently lumped under Gymnodoris alba so we'll leave those alone for now because we are anticipating a paper being published soon on the Gymnodorididae and can hardly wait until then. However there was a definite discrete new species sighted on this dive - Gymnodoris sp. 9.

This brings us to the new Dermatobranchus. Dermatobranchus sp. 6 has distinct ridges (far more than described for D. rodmani) together with pink pustules on the mantle edge whilst in the second photo  a vivid red edge with submarginal yellow to the oral veil is shown. It is most similar to Dermatobranchus funiculus but does not match that description in its entirety.

We have decided to be wary of lumping together specimens with some similarities but also definite differences because by keeping them separate they will not be lost for future investigation. For far too long the term highly variable has been bandied about. Who is to know for sure which features are highly variable until precise examination has been undertaken. In fact, recent DNA investigations combined with a broader study of internal anatomy have found cryptic species among a number of species across the sea slug orders.

Number of species sighted
* Species with highest specimen count

Bulbaeolidia alba -2
Dermatobranchus cf. primus -10
Dermatobranchus sp. 6 -2 (new species)
Facelina sp. 7 -1
* Goniobranchus daphne -20
Goniobranchus decorus -1
Gymnodoris alba -5
Gymnodoris sp. 1 -1
Gymnodoris sp. 9 -1 (new species)
Hydatina physis -1
Hypselodoris obscura -5
Phidiana bourailli -1
Philinopsis pilsbryi -1
Pteraeolidia ianthina -5
Siphopteron sp. 1 -1 (new species)
Unidentia angelvaldesi -3

Preparing for immersion


Bulbaeolidia alba

Goniobranchus decorus

Philinopsis pilsbryi 
Scooting around in broad daylight

Hydatina physis - appears to have been 
cracked open by a crab perhaps.

Facelina sp. 7

Dermatobranchus cf. primus

Goniobranchus daphne

Dermatobranchus sp. 6 (New species)

Dermatobranchus sp. 6 (New species) 
Note colour of oral veil

Goniobranchus daphne - a mating pair

Hypselodoris obscura

Pteraeolidia ianthina

Unidentia angelvaldesi

Gymnodoris alba

Gymnodoris sp. 1

Gymnodoris sp. 9 (New species)

Siphopteron sp. 1 (New species)

Siphopteron sp. 1

Tuesday, December 2, 2014

Species List: Castle Rock, Bicheno, Tasmania 24, 25, 26-11-2014

9 species were found and 7 new species were added to the big Tasmania list over the 3 days diving with David. We chartered the boat at Bicheno Dive and was treated with great nudibranch dive time. 14C water temp, light winds, 15m vis, average dive 1 hour.

Number of species sighted
* Species with highest specimen count

Cadlina tasmanica  1
Caldukia affinis  10
Ceratosoma amoenum  2
Ceratosoma brevicaudatum  1
Colpodaspis sp. 1  1
Flabellina poenicia  1
Janolus eximius  1
*Polycera janjukia  12

Tularia bractea  8

David ready to go at Govenors Island boat ramp

David falling down the canyon

The substrate

Colpodaspis sp. 1

Polycera janjukia

Janolus eximius thought to endemic to NZ

Caldukia affinis

Ceratosoma brevicaudatum

Cadlina tasmanica

Polycera janjukia

Tularia bractea