Chelidonura berolina = C. africana [2]

March 15, 2004
From: Bill Rudman

In an earlier message [#11810] I suggested that the Caribbean species C. berolina, was most probably a western population of the eastern Atlantic - Mediterranen species C. africana. Recent photos from Marina Poddubetskaia [#12418] confirm this view. 'Typical' C. africana from the eastern Atlantic seems to be black with white speckling and yellow and blue markings in a characteristic pattern, as illustrated by Pruvot-Fol. In the western Atlantic however, although these typical colour forms can be found, there are also animals with a brownish background colour as well. Colin Redfern's recent message [#12445] illustrates this and also shows the similarity in shell shape on both sides of the Atlantic.

In summary, I think we can say that the basic colour pattern is black with a yellow border to the parapodia and posterior shield and a yellow band across the head, some distance back fron the edge. Often the yellow lines are broken into a series of spots, and in some cases the yellow is absent. There are blue spots forming a sub marginal row on the parapodia and there can be blue spots on the inside of the 'tails' of the posterior shield. The blue spots can sometimes be absent, and sometimes are greatly enlarged. There is a wide translucent white band across the front of the head shield. In most animals, but not all, there are white specks and patches scattered over the body. Sometimes the white predominates, producing an animal which could be best described as white with black speckling. There is usually a large white patch on the posterior tip of the head shield, which can sometimes be yellow or edged in yellow. Colin Redfern's photo [#12445] also suggests that the background colour can at times be brown rather then black.

As I have discussed earlier, it seems a number of names for Caribbean animals refer to this species.

• C. berolina Marcus & Marcus, 1970 - Marina Poddubetskaia's Photo E [#12418] is almost identical in colour to the original illustration of this animal. The population illustrated in Marina's messages show clear gradations in colour to forms identical to Pruvot-Fol's specimens from Morocco. Ortea & Martinez, (1997), suggest that this species is a juvenile of Chelidonura hirundinina, but the colour markings, and the shape of the posterior lobes are quite different.
• C. hummelincki Marcus & Marcus, 1970. As discussed earlier, no information is available on the colour of the living animal so it cannot be definitively identified. It is most likely a heavily speckled form of this species.

Ortea & Martinez (1997), in their description of Chelidonura cubana, suggest that C. africana, C. leopoldoi Ortea, Moro & Espinosa, 1996, C. hummelincki and C. cubana, are similar but distinct. Another small species from the Caribbean with a similar colour pattern, Chelidonura juancarlosi Ortea & Espinosa, 1998, was described a year later. All these species were described from very few specimens. I would not be at all surprised if further investigations show that these species are all colour variants of C. africana

References:
• Marcus, Er. & Marcus, Ev. (1970) Opisthobranchs from Curacao and faunistically related regions. Uitqaven van der Natuurwetenschappelijke Studiekring voor Suriname en de Nederlandse Antillen, 59: 1-129.
• Ortea, J., Moro, L. & Espinosa, J. (1996) Descripcion de dos nuevas especies del genero Chelidonura A.Adams, 1850 (Opisthobranchia, Cephalaspidea, Aglajidae) colectadas en la Isla del Hierro. Estudio comparado con C. africana Pruvot-Fol, 1953. Rev. Acad. Cabar. Cienc., 8: 215-229.
• Ortea, J. & Martinez, E. (1997) A new species of Chelidonura A.Adams, 1850 (Mollusca: Opisthobranchia: Cephalaspidea) from Cuba shores (in Spanish). Avicennia, 6/7: 137-140.
• Ortea, J. & Espinosa, J. (1998) Two new species of marine Mollusks (Mollusa: Gastropoda) colleted in the subarchipelagoes Jardines del Rey and jardines de la Reina, desribed in honor of the King and Queen of Spain for their first visit to Cuba. Avicennia, 8/9: 1-6.

Best wishes
Bill Rudman

Rudman, W.B., 2004 (Mar 15) Chelidonura berolina = C. africana [2]. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/12457

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