Zoölogisch Museum

Bulletin Zoölogisch Museum UNIVERSITEIT VAN AMSTERDAM Vol. 15 No. 9 1996 The rediscovery of Cervera atlantica (Johnson, 1861) (Cnidaria: Octocorallia): notes on its identification, ecology and geographical distribution R.B. Williams Key words: Octocorallia, Cervera atlantica, Cornularia cornucopiae, identification, ecology, zoogeography. Abstract Cervera atlantica, a small stoloniferan octocoral, was described as Cornularia atlantica by James Yate Johnson in 1861 from Funchal, Madeira. It then remained unrecognized until 1972 when I discovered it on the Mediterranean coast of Spain. I have since confirmed its existence at the type locality and have traced its distribution around Madeira, throughout the Canary Islands, and on Portuguese and coasts. In the have found it and English Mediterranean Sea, I along Spanish French coasts, among the Balearic Islands and on the coast of Cyprus. Cervera atlantica is cryptic and photophobic, living under stones in shallow water (usually at 0-2 m) or in crevices and caves in massive intertidal rocks, protected from direct sunlight. Intolerantof rough water, it usually occurs in sheltered bays, on beaches protected in the lee headlands. In with it the by reefs, or of common Cornularia cornucopiae, occurs throughout Mediterranean, but only very rarely in been the same habitat.There may have confusionbetween these two species for many years, as Cervera atlantica is apparently rather more common than Cornularia cornucopiae, which hithertohas been generally regarded as the only non-scleritic stoloniferan existing in the Mediterranean. In the Atlantic, Cervera atlantica has a Lusitanian-Mauritaniandistribution, occurring both north and south of the Strait of its limits of Gibraltar, although are not yet known. Records Cornularia cornucopiae in the Atlantic are rather rare, only to the north of Gibraltar. In view of the potential confusion with Cervera atlantica, those records need to be confirmed. INTRODUCTION Iberian Peninsula and southern England, and also In 1861, James Yate Johnson published "an account of throughout the Mediterranean Sea. such Sea-Anemones as have occurred to me after much diligent search in the neighbourhood of Funchal, the capi- tal of Madeira". He included a description of Cornularia HISTORICAL ACCOUNT atlantica "for Sea- For of sp. n., although not, strictly speaking, a ease comparison with my own observations, the it resembles in external of Anemone, closely one appear- original description Cornularia atlantica Johnson, 1861 ance" (Johnson, 1861). is given here. The SI equivalents of the original imperial This small stoloniferan octocoral has been overlooked measurements are given in square brackets. for well over a century, and as far as I know, no reference "Basal band narrow, inconspicuous, creeping irregular- to it appeared in the scientific literature since it was origi- ly, and bearing the polypes at uncertain distances. Column until nally described, very recently (viz., Lôpez-Gonzâlez, of a pale flesh-colour, subcylindrical, rather wider at the Ocarïa, Garcia-Gômez & Nûnez, 1995; Williams, 1996). In middle than above and below; destitute of spicula, but 1972, I discovered Cornularia atlantica on the Mediterra- invested by a thin epidermis containing particles of sand; of nean coast Spain. In the ensuing years I have confirmed when retracted, forming a fleshy hemispherical button, its presence at the type locality and have found it to be one-fifteenth of an inch [1,7 mm] high; when expanded, the widespread and locally common around Madeira and the column has a length of about three-tenths of an inch [7.6 well the Atlantic of the Canary Islands, as as on coasts mm], with a diameter of one-twelfth of an inch [2.1 mm]. 66 Eight pinnate tentacles, in one series, at the margin of the unableto find A. inermis in the field, nor could he find any of about shallow cup forming the disk, the pinnae twelve type material in several European museums, and com- pairs, ringed, as if showing a tendency to further division. mented that it "therefore remains rather enigmatic". Tentacle-stem subulate, about one-fourth of an inch [6.4 However, he correctly concluded from the description of mm] in length, the bases of the tentacles broadening and Bérenguier (1954) that A. inermis belongs neither to the in with another each side. When coming contact one on genus Anthelia (which has non-retractile polyps), nor to the the animal is fully displayed, the tentacles and the upper genus Clavularia (which has sclerites). He also believed part of the column are nearly colourless, and have the that it was not conspecific with Cornularia cornucopiae film. appearance of a transparent Abundant on stones (Pallas, 1766), and suggested that it might belong to a near low-tide mark; sometimes attached to sea-weed." genus of its own. It is therefore puzzling that he later 1861: A. to [Johnson, 298-299]. (Weinberg, 1986) assigned inermis the genus locate the of Cornu- Clavularia In an attempt to type specimen(s) ; particularly since, in 1979, I gave him a speci- laria atlantica, I searched the three museum collections men of a then unidentified stoloniferan without sclerites which seemed most likely to include material donated by that I had collected from Benidorm, which he subsequently J.Y. Johnson. The first two are in Funchal, Madeira. deposited under the name of Anthelia inermis in the According to Norman (1909), Johnson's collection was Zoôlogisch Museum, Universiteit van Amsterdam (Table I). held in 1908 by the Museu do Seminârio, cared for by Only later did I determine the Benidorm species as Padre Ernesto Schmitz. The collections of this museum Cornularia atlantica. were transferred in 1982 to the Jardim Botânico da The stoloniferan that Manuel (1979) reported to occur Madeira to form the nucleus of the present Museu de in Portland Harbour, England was misidentified as Cornu- Histôria Natural. Unfortunately, little of Johnson's cnidarian laria cornucopiae. I have recently confirmed that this material has survived there: a careful search of the avail- stoloniferan can still be found there and is, in fact, clearly able specimen tubes and microscope slides did not reveal identifiablewith Cornulariaatlantica. any specimens of Cornularia atlantica. The other collection that I examined in Funchal, again without success, was that of the Museu Municipal do Funchal. Since Johnson SYSTEMATICS frequently sent material to his friends in England, I also Since the original typescript of this paper was written (an searched the cnidarian collection of the British Museum abstract has already appeared (Williams, 1996)), a paper (Natural History), which, however, also contained no speci- by Lôpez-Gonzàlez et al. (1995) dealing with Cornularia mens of Cornularia atlantica. Examination of a small col- atlantica has been published. I have thus been saved the lection of in that trouble of for Cornularia atlan- microscope slides, now my possession, establishing a new genus once belonged to Canon A. M. Norman, a friend of John- tica, an intention that I communicated to the two senior Since Cornularia son, revealed no relevant material. authors in a letter dated 29 April, 1991. of Although not recognized as such, Cornularia atlantica atlantica is now designated as the type species Cervera Garcia-Gomez was found in the Mediterranean Sea near Marseille, Lôpez-Gonzâlez, Ocana, & Nunez, 1995, it France, by Bérenguier (1954), who described it as a new will hereafter be referred to as Cervera atlantica. species, Anthelia inermis. Some extracts are given here from the original description of A. inermis and may be Cervera atlantica (Johnson, 1861 ) compared with the original description of Cornulariaatlanti- ca Johnson, 1861: the conspecificity of these taxa is Synonyms: Cornulariaatlantica Johnson, 1861 immediately apparent (Williams, 1996) and their names Anthelia inermis Bérenguier, 1954 first time. “Anthelia” inermis: are, therefore, formally synonymized here for the Weinberg (1978) Cornularia Manuel "Enfin, on rencontre, dans une calanque située devant cornucopiae: (1979,1981, la Station Marine d'Endoume, fixée sous les pierres, à une 1983,1988); Picton étal. (1987) profondeur de 50 cm. environ, une espèce tout à fait parti- Clavularia (“Anthelia”) inermis: Weinberg culière dAnthelia. Les stolons membraneux de ces (1986) colonies d'Anthelia sont, le plus souvent, recouverts d'une ? Cornulariainermis: Roca (1986) couche mucilagineuse. Les polypes, isolés ou groupés en Cervera atlantica: Lôpez-Gonzàlez étal. bouquets, sont presque globuleux lorsqu'ils sont complète- (1995) Cornularia atlantica: Williams ment rétractés. Ils sont protégés par une gaîne formée de (1996) corpuscules divers agglomérés. Epanouis, les polypes très lais- The is based from s'allongent beaucoup. Leurs tissus, transparents, following description upon specimens sent voir le tube digestif. Les huit tentacules pinnés ont all the localities in the Atlantic Ocean, the English Channel chacun un renflement à leur base [cette espèce] est and the Mediterranean Sea where I have found Cervera ... de 1954: There marked between of totalement dépourvue spicules." [Bérenguier, atlantica. are no differences any 61], the colonies collected. Their features are also, on the described Weinberg (1978), who had carried out a detailed sur- whole, consistent with those by Johnson (1861), of the Mediterranean was Manuel and vey circalittoral Octocorallia, Bérenguier (1954), (1979, 1981, 1983, 1988) 67 Fig. 1. Comparative diagrams, to the same scale, of parts of colonies of

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