July 28, 2000
From: Lindsay Warren
This Costasiella was found by Rich Smith on 21 June 1999 at a depth of 7.1m on rubble on an underwater pinnacle next to Pulau Hoga [Tukang Besi Archipelago, SE Sulawesi, Indonesia - Operation Wallacea]. Size: 3 mm.
Although similar to Costasiella sp. 1 he found in 1998 and which you posted on the Forum, there are several differences which may or may not be significant. The first is that the rhinophores of this specimen narrowed down towards the end and were covered in colourful speckles whereas the 1998 specimen had rhinophores of the same diameter along their length and were entirely white. The second difference is the black marking between and behind the rhinophores [see sketch at bottom left]. A third difference is that there were colourful specklings on the tail in this specimen and none on the 1998 one [see sketch at upper right] . Illustrations: Rich Smith, Photo: Lindsay Warren.
Incidentally I noticed that the photo from 1998 was credited to me whereas it should in fact be credited to Adam Powell.
Do you think it is the same species or a different one?
All the best
Warren, L., 2000 (Jul 28) Costasiella sp. 1 from Sulawesi. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2741
I think we are in trouble if those differences are significant. I am sure that your two animals fit within the normal range of variation to be found in that species. Clay Carlson & Patty Jo Hoff's animal is also probably the same species, which would suggest the black markings between the rhinophores are a quite important character. It is possible that some of the more brilliant iridescent speckling becomes less noticeable as the animals grow and/or become more pigmented.
I will change the photo credit.
Costasiella sp. 1.? from Okinawa.
From: Yasuhiro Shamoto, August 14, 2007
Re: Costasiella from Hawaii
From: Clay Carlson, November 17, 2003
Costasiella from Hawaii
From: Dan Barshis, November 16, 2003
Costasiella from Okinawa
From: Atsushi Ono, April 28, 2002
Re: Costasiella sp. 1 from Hawaii
From: Kathe R. Jensen, February 7, 2002
Costasiella sp. 1 from Hawaii
From: Cory Pittman, February 6, 2002
Costasiella sp. 1. from South Africa
From: Valda Fraser, February 5, 2002
Costasiella sp. 1 from South Africa
From: Lindsay Warren, February 5, 2002
Re: Colour in Costasiella
From: Clay Carlson & Patty Jo Hoff, March 25, 1999
Chemical defence in Costasiella
From: Bill Rudman, March 24, 1999
Costasiella sp. 1. from Guam
From: C Carlson & P.J. Hoff, March 23, 1999
Costasiella sp from Sulawesi
From: Lindsay Warren, March 20, 1999