Coronula diadema

Coronula diadema (and a Concoderma auritum), on whales, boring in their skin, Photo: Michael Lahanas

Life-forms

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Protostomia
Cladus: Ecdysozoa
Cladus: Panarthropoda
Phylum: Arthropoda
Cladus: Pancrustacea
Superclassis: Multicrustacea
Classis: Thecostraca
Subclassis: Cirripedia
Superordo: Thoracica
Ordo: Sessilia
Subordo: Balanomorpha
Infraordo: Neobalanoformes
Superfamilia: Coronuloidea

Familia: Coronulidae
Subfamilia: Coronulinae
Genus: Coronula
Species Coronula diadema
Name

Coronula diadema (Linnaeus, 1767: 1108)
Original genus: Lepas
Geological ageː early Pliocene to Recent
Symbiont: obligate commensal on skin of cetaceans
Type locality: Mediterranean Sea
Types:
Distribution: cosmopolitan, preferring baleen whales
ZooBank: CC10CA6B-E0FB-4D07-9C0C-2522DEC31827

Synonyms

Lepas balaenera Müller, 1776: 250, item 3024
Balanus balaena Da Costa, 1778: 251
Diadema vulgaris Schumacher, 1817: 91
ZooBank: AD776634-D1FC-497E-910F-8110F499FFE8
Diadema candidum Ranzani, 1818: 88
ZooBank: B1849154-577A-4094-A470-40429BF68963
Polylepas (Diadema) kleinii Gray, 1825: 105
Synonymized in Pilsbry, 1916: 273
ZooBank: 1E0D49FC-BB68-4007-B14C-108DCD2029E6
Coronula biscayensis Van Beneden, 1870
no description
?Coronula japonica Van Benedin, 1870
no description, taken from Japanese drawing
Coronula californica Van Benedin, 1870
no description
†Coronula macsotayi Weisbord, 1971: 91
Synonymized in Buckeridge, Chan & Lee, 2018
See taxon page for full information
Diadema antiquum Philippi, 1887: 226
Synonymized in Newman & Ross, 1976: 45
Tertiary, Strand von Arauco, Chile
ZooBank: 9EADEA89-3224-4DCA-BE42-DE1475DF3C50

References

Linnaeus, C. 1767. Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Editio duodecima, reformata. Tomus 1 (Regnum Animale), Pars 2: 533–1327. Holmiæ [Stockholm]. Impensis Direct Laurentii Salvii. Biblioteca Digital BHL Reference page. [See p. 1108, original description]

Beu, A.G. 1971. Further fossil whale barnacles from New Zealand. New Zealand journal of geology and geophysics, 14(4): 898–904. DOI: 10.1080/00288306.1971.10426337 Reference page. [See p. 902, New Zealand material]
Bruguiere, M. 1789–1791. Encyclopedie methodique. Histoire naturelle de Vers 1(1): 158–178. (French) BHL Reference page. [See Pl. 164, fig. 13, 14, as Balanus diadema]
Buckeridge, J.S., Chan, B.K-K. Lee, S-W. 2018. Accumulations of fossils of the whale barnacle Coronula bifida Bronn, 1831 (Thoracicaː Coronulidae) povides evidence of a late Pliocene Cetacean migration route through the Straits of Taiwan. Zoological Studies 57ː 54. DOI: 10.6620/ZS.2018.57-54 Open access Reference page.
Darwin, C. 1854. A monograph on the sub-class Cirripedia with figures of all species. Vol. 2: The Balanidae, The Verrucidae. BHL London: Ray Society. Reference page. [See p. 417, re-description, discussion]
Newman, W.A.; Ross, E. 1976: Revision of the balanomorph barnacles; including a catalog of the species. Memoirs of the San Diego Society of Natural History, (9) BHL Reference page. [See p. 45, extensive bibliography]
Pilsbry, H.A. 1916: The sessile barnacles (Cirripedia) contained in the collections of the US National Museum; including a monograph of the American species. Bulletin of the United States National Museum, (93) DOI: 10.5962/bhl.title.1144 Reference page. [See p. 273, see for pre-Darwin synonymy]
Ross, A. & Frick, M.G. 2011. Nomenclatural emendations of the family-group names Cylindrolepadinae, Stomatolepadinae, Chelolepadinae, Cryptolepadinae, and Tubicinellinae of Ross & Frick, 2007—including current definitions of family-groups within the Coronuloidea (Cirripedia: Balanomorpha). Zootaxa 3106: 60–66. Preview Reference page. [See p. 64]

Coronula diadema is a species of whale barnacle that lives on the skin of humpback whales and certain other species of whale.[2] This species was first described by Carl Linnaeus in the 1767 12th edition of his Systema Naturae.[1]
Description

As its name suggests, Coronula diadema resembles a crown in appearance, but as it grows it becomes more cylindrical; large specimens may be 5 cm (2 in) tall and 6 cm (2.4 in) in diameter. There are six broad wall plates surrounding a hexagonal orifice at the top, which is protected by a pair of opercular valves. The plates have fine longitudinal striations and the lower half often have irregular transverse striations.[3]
Distribution and habitat

C. diadema is found on the external surface of whales. When discussing this species, the zoologist Charles Darwin (who devoted much of his career to barnacles) stated that he knew of the precise locations where four specimens were found, the arctic seas around Scandinavia, the east coast of North America, near the coast of the British Isles, and from the Gulf Stream. Another reported location was New Zealand, but Darwin suspected that this was an error, and might be Coronula reginae.[3] The host whales are mostly baleen whales, particularly humpback whales (Megaptera novaengliae), with the barnacles attaching themselves to the head, the flukes, the flippers, various grooves and the genital slit.[4] This barnacle has also been found on the blue whale (Balaenoptera musculus), the southern right whale (Eubalaena australis), the fin whale (Balaenoptera physalus), the sperm whale (Physeter macrocephalus) and the northern bottlenose whale (Hyperoodon ampullatus).[5]

For 'the role of Coronula diadema on a humpback whale's pectoral fins helping it to defend its calves from killer whales, see Humpback whale#Fins.
Life cycle

Most barnacles are hermaphrodites and can fertilíze each other but not themselves, so they need to be clustered closely together to be able to breed. An individual acting as a male extends his long penis to impregnate the mantle cavity of another individual in close proximity. Here internal fertilisation takes place and the embryos are brooded until the first moult.[6] The free-swimming nauplius larvae form part of the plankton and pass through six moults before becoming non-feeding cyprid larvae. Laboratory experiments suggest that the cyprid larvae are induced to settle and undergo metamorphosis into juvenile barnacles in response to chemical cues from the skin of suitable host whales.[7]

References

Alan Southward (2015). "Coronula diadema (Linnaeus, 1767)". WoRMS. World Register of Marine Species. Retrieved 28 January 2016.
Zullo, Victor A. (April 1979). Marine Flora and Fauna of the Northeastern United States: Arthropoda: Cirripedia (PDF). NOAA Technical Report NMFS Circular. Vol. 425. National Oceanic and Atmospheric Administration. p. 29.
Darwin, Charles (2010). The Works of Charles Darwin, Volume 12: A Monograph of the Sub-Class Cirripedia, Volume II: The Balanidae (Part One). NYU Press. pp. 370–371. ISBN 978-0-8147-2055-4.
Perrin, William F.; Würsig, Bernd; Thewissen, J.G.M. (2009). Encyclopedia of Marine Mammals. Academic Press. p. 90. ISBN 978-0-08-091993-5.
Hayashi, R. (2013). "A checklist of turtle and whale barnacles (Cirripedia: Thoracica: Coronuloidea)". Journal of the Marine Biological Association of the United Kingdom. 93 (1): 149–155. doi:10.1017/S0025315412000847.
Ruppert, Edward E.; Fox, Richard, S.; Barnes, Robert D. (2004). Invertebrate Zoology, 7th edition. Cengage Learning. p. 683. ISBN 978-81-315-0104-7.
Nogata, Yasuyuki; Matsumura, Kiyotaka (2006). "Larval development and settlement of a whale barnacle". Biology Letters. 2 (1): 92–93. doi:10.1098/rsbl.2005.0409. PMC 1617185. PMID 17148335.