Crosslandia sp. 1

Order: NUDIBRANCHIA
Suborder: DENDRONOTINA
Family: Scyllaeidae

PHOTO

North western Pacific coast of Costa Rica, approx 15ft. Length: approx 1cm. Photo: Peter Ajtai.

The only species described from the eastern Pacific is Crosslandia daedali Poorman & Mulliner, 1981. It differs in shape and colour from that species, and certainly in shape from the Indo-West Pacific species Crosslandia viridis.

Authorship details
Rudman, W.B., 2002 (May 15) Crosslandia sp. 1 [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/crossp1

Related messages


Radula of Crosslandia sp. 1

September 14, 2002
From: Peter Ajtai

Dear Bill,
I sent a message a while back about finding a Crosslandia species. It is now grouped under Crosslandia sp 1on your site.

During June I got a chance to visit the California Academy of Sciences, and with the gracious help of Yolanda Camacho got these scanning electron microscope images of the radula and jaw elements of the Crosslandia. Looking at these, I'm pretty sure it is in fact Crosslandia daedali. What do you think?
Take care,
Peter Ajtai.

ajtai@slugophile.org

Ajtai, P., 2002 (Sep 14) Radula of Crosslandia sp. 1. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7802

Dear Peter,
Thanks for the photos. There is very little published information on the radular morphology of the scyllaeids, so I have added SEM photos today of the radulae of Scyllaea pelagica, Notobryon wardi, and Crosslandia viridis.

Your radula, with the spaced first lateral and central teeth, is most like that of Crosslandia viridis but the tuberculate jaw rodlets are a bit of a puzzle. According to Thompson & Brown (1981)
Scyllaea has this sort of jaw rodlets, while Crosslandia has smooth ones. Unfortunately my jaw mounts for these animals were a disaster, and I can't find any other published description to confirm Thompson & Brown's findings. Clearly this needs reinvestigating. In the mean time I assume your animal is a species of Crosslandia. However, the only information we have on the radular morphology of C. daedali are line drawings from light microscope mounts in the original description. These are not easily comparable with SEM photos, and until we have a better idea of the radular morphology of all the scyllaeids, there is very little to compare your radula with. The general shape and colour of your animal still looks rather different from what could be called 'typical' C. daedali. That is not to say it is not C. daedali, but at present I have no convincing evidence to say it is.
Best wishes,
Bill Rudman

Rudman, W.B., 2002 (Sep 14). Comment on Radula of Crosslandia sp. 1 by Peter Ajtai. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7802

Crosslandia? in Costa Rica

April 22, 2002
From: Peter Ajtai


Hello Bill,
I found this sea slug on leaves of Halimeda off the north western Pacific coast of Costa Rica. I think I have this guy narrowed down to Crosslandia daedali or C. viridis, but I do not know how to tell the two apart. What do you think? It was at a depth of about 15ft and is about 1cm long.

Best wishes,
Peter Ajtai.

ajtai@slugophile.org

Ajtai, P., 2002 (Apr 22) Crosslandia? in Costa Rica. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6737

Dear Peter,
This is an interesting find. It is indeed a species of Crosslandia but we know so little about the species of this genus that distinguishing them from one another is still a game of guesswork. I don't know why they seem to be so rare, perhaps they are just very well camouflaged. The only species described from the eastern Pacific is Crosslandia daedali Poorman & Mulliner, 1981, so until we know more about its relationship with the Indo-West Pacific species such as C. viridis, I guess it is best to identify it as C. daedali. As far as I know it has only previously been reported from Baja California Peninsula.

• Poorman, L.H. & Mulliner, D.K. (1981) A new species of Crosslandia (Nudibranchia: Dendronotacea) from the Gulf of California. The Nautilus, 95(2): 96–99.

Best wishes,
Bill Rudman

Rudman, W.B., 2002 (Apr 22). Comment on Crosslandia? in Costa Rica by Peter Ajtai. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6737