Goose barnacles, also called percebes or turtle-claw barnacles or stalked barnacles or gooseneck barnacles, are filter-feeding crustaceans that live attached to hard surfaces of rocks and flotsam in the ocean intertidal zone. Goose barnacles formerly made up the taxonomic order Pedunculata, but the group has been found to be polyphyletic, with its members scattered across multiple orders of the infraclass Thoracica.
The Chthamalidae are a family of chthamaloid barnacles, living entirely in intertidal/subtidal habitats, characterized by a primary shell wall of eight, six, or four plates, lacking imbricating plate whorls, and either membraneous or more rarely calcareous basis. They are not found below immediate subtidal habitats, and more likely are found in the highest tier of shallow-water barnacle fauna. They can be found in the most rigorous wave-washed locations, and some species are found in the surf zone above high tide mark, only receiving water from wave action at high tide. The family includes at least 56 recognized species.
Whale barnacles are species of acorn barnacle that belong to the family Coronulidae. They typically attach to baleen whales, and sometimes settle on toothed whales. The whale barnacles diverged from the turtle barnacles about three million years ago.
Lepas anserifera is a species of goose barnacle or stalked barnacle in the family Lepadidae. It lives attached to floating timber, ships' hulls and various sorts of flotsam.
Notochthamalus scabrosus, the only species in the genus Notochthamalus, is a species of barnacle found along the south-western and south-eastern coasts of South America, from Peru to the Falkland Islands. The species is found almost exclusively higher in the intertidal zone than the mussel Perumytilus, often codistributed with the confamilial barnacle Jehlius cirratus and Balanus flosculus.
The Chthamaloidea are a subdivision of Balanomorpha proposed by Newman and Ross to include barnacles with shell wall composed of rostrum, carina, and one to three pairs of latera, rarely supplemented with one or more whorls of basal imbricating plates. The rostrolatus enters the sheath, but rarely fuses with the rostrum, as in the three higher superfamilies. Shell plates are simple in construction, solid, and incorporate organic chitin between carbonate layers. Opercular plates are deeply interlocked, and in some genera, may become concrescent with age. Soft part morphology includes concave labrum without notch in the central part. Cirrus III more resembles Cirrus IV than II, or may be intermediate in structure. Caudal appendages present in some species.
Pseudoctomeris sulcatus is a species of barnacle, the only member of the genus Pseudoctomeris. It has an eight-plated shell wall with the rostrum partially fused with adjacent rostrolatera. The suture lines are visible only from the inside, thus in exterior view, the shell appears to have six wall plates. The basis is calcareous. Opercular plates are higher than wide, and not deeply articulated. These features and others show strong relationship to family Pachylasmatidae, and taxonomic revision of Pachylasmatidae has resulted in the transfer of Pseudoctomeris from Chthamalidae to Pachylasmatidae.
The Catophragmidae are a family of barnacles in the superfamily Chthamaloidea with eight shell wall plates, surrounded by several whorls of imbricating plates. The basis is membranous.
Catomerus is a monotypic genus of intertidal/shallow water acorn barnacle that is found in warm temperate waters of Australia. The genus and species is very easily identified by whorls of small plates surrounding the base of the primary shell wall; no other shoreline barnacle species in the Southern Hemisphere has that feature. This species is considered to be a relic, as these plates are found only in primitive living lineages of acorn barnacles or in older fossil species. The fact that this is an intertidal species is unusual, because living primitive relic species are often found in more isolated habitats such as deep ocean basins and abyssal hydrothermal vents.
Catophragmus is the originally named genus of the family Catophragmidae. At present, it is monotypical. It is a shallow water acorn barnacle of the Tropical Western Atlantic and Caribbean characterized by small accessory imbricating plates surrounding the base of the shell wall.
Chamaesipho is a genus of four-plated notochthamaline barnacles in the Pacific Ocean limited to Australian/New Zealand temperate waters. They are intertidal in preference, and tend to form crowded columnar colonies. They can be identified in the field by having a four-plated wall, an unfused rostrum, and narrow opercular plates. Elminius, which also inhabits the same area, has four plates in its shell wall. However, in Elminius, the rostrum and rostrolatera are fused completely, and the compound rostrum receives the alae of the adjacent carinolaterals. In Chamaesipho, the unfused rostrum bears alae, and closely resembles the carina in appearance.
Chamaesipho brunnea is an intertidal barnacle common in New Zealand, in both the North Island and the South Island. Juveniles have six shell wall plates, reducing to four in adults, and with age, all plates become concrescent, with no trace of sutures inside or out. Shell is brown colored. The related, and sometimes associated Chamaesipho columna is much smaller in size, by nearly half, while Elminius, which can associate with both species, also has four shell wall plates, but plates remain distinct at all stages. The shell of C. columna corrodes to a pitted surface, while that of C. brunnea has a lamellar corrosion.
Chamaesipho tasmanica is an intertidal shoreline barnacle of Australia. Its principal range centers in New South Wales, and Tasmania. Columnar colonies can be found on high intertidal rocks relatively free of dense seaweed. Individuals are small, less than 15 mm, and grayish in color.
Chamaesipho grebneffi is the first extinct member of the Notochthamalinae to be described, and the oldest chthamaloid barnacle known. This species is a fully derived Chamaesipho, and indicates a considerable antiquity for Chthamaloidea.
Rehderella is an unusual and monotypic barnacle genus restricted to Easter Island and Pitcairn Island. Rehderella belyaevi is its only species.
The barnacle genus Nesochthamalus was erected by Foster & Newman, 1987, to include sole species Chthamalus intertextus originally named by Darwin in 1854. It is widespread on islands in Western Pacific Ocean, including Hawaii, and presents combinations of unusual features which make easily recognizable for field workers. These include dirty white shell exterior with deep purple colored interior, operculars colored purple. Opercular plates on each side calcify together in all but youngest individuals, and cannot be separated or easily distinguished from each other. This feature is shared only by Rehderella belyaevi, but in latter species, scutum and tergum can be distinguished by raised ridge replacing old articular margin. Unique feature of Nesochthamalus is its basis. In young individuals, it is entirely membraneous, and with age, becomes secondarily calcareous progressively inwards, leaving only the center membraneous. As the basis calcifies, it rises off the substrate forming a saucer shape when viewed from the side. In addition, interior of shell is secondarily calcified.
Coronula diadema is a species of whale barnacle that lives on the skin of humpback whales and certain other species of whale. This species was first described by Carl Linnaeus in the 1767 12th edition of his Systema Naturae.
Vulcanolepas osheai, commonly referred to as O'Shea's vent barnacle, is a stalked barnacle of the family Neolepadidae. This species is endemic to New Zealand.
Conchoderma virgatum is a species of goose barnacle in the family Lepadidae. It is a pelagic species found in open water in most of the world's oceans attached to drifting objects or marine organisms.
Lepas testudinata is a species of goose barnacle in the family Lepadidae. First observed in 1834, Lepas testudinata has undergone several reclassifications, and its relationship to other Lepas species is still the subject of ongoing research. L. testudinata is endemic to temperate waters in the China Seas, Australian Sea, and the Indo-West Pacific, and there are two distinct subgroups within the species. This barnacle species exclusively colonizes free-floating debris and tidewrack, and can form colonies of over 1000 members at a time. Due to this colonization habit, L. testudinata plays a role in biofouling and often serves as a foundation species when preyed upon.
