Chartella barleei is a northern bryozoan species, ranging from the Barents Sea, along the coasts of Norway to the Shetland Isles and the northern coasts of the UK. The species has also been recorded from the northern coast of Spain and deep water in the Bay of Biscay.
Colonies are typically found on hard substrates in moderately deep (down to 1000 m) waters, but may be found at shallower depths in the northern part of their range. Chartella barleei forms short lobate colonies with flattened branching fronds. Fresh colonies are very thin and delicate. Colonies appear light coloured or transparent and rarely exceed 5 cm in height.
Colonies grow through asexual budding of new zooids at the periphery.
Chartella barleei has a similar colony form to several other species in the family Flustridae. Chartella barleei can be distinguished from C. papyracea -the only other species of the genus to occur in Britain - by the absence of spines at each distal corner of the zooids, and the presence of avicularia.
Colonies form short tufts of radiating fronds, which divide into segments near the base and then again sub-divide into shallow blunt lobes toward the tip. Colonies narrow towards the base before terminating in an encrusting sheet of zooids that adhere to the substrate. Colonies are very delicate, thin and transparent, rarely exceeding 5 cm in height.
Zooids are approximately rectangular, hexagonal or irregular in shape, and lack spines. The frontal surface of the zooids is entirely membranous, with very thin, lightly calcified lateral walls allowing the colony to be flexibile. The zooids are arranged “back to back” to form bilaminar sheets and specialised zooids, which lack feeding apparatus (kenozooids), border the edge of each frond. The kenozooids are generally smaller than feeding zooids, only very occasionally exceeding them in length.
Opercula (flap-like folds of the body wall which close the orifice) have a broad, marginal thickened line (scelrite). Small square, rectangular or irregular quadrangular avicularia are interposed between zooids in a longitudinal series. The circular rostrum is positioned at an angle both to the axis and the plane of the colony surface. The mandible is semi-circular.
Colonies typically grow up to 5 cm in height. Zooids are 0.72-1.0 by 0.3 – 0.5 mm
Chartella barleei is a boreal, sub-arctic bryozoan species, ranging from the Barents Sea along the coasts of Norway to the Shetland Isles, the western coasts of Scotland and the northern coasts of the UK. The species has also been recorded from the northern coast of Spain and the deep water of the Bay of Biscay. Not thought to occur in the Mediterranean.
Chartella barleei is a sub-arctic, boreal species occurring in the eastern Atlantic. It is most frequently found on hard substrates including shells, gravel, rock and coral rubble. Colonies are found in moderately deep waters, but may occur at shallower depths in the northern part of the species’ range.
The founding zooid (ancestrula) develops into a young colony, and later into an adult colony through asexual budding. Sexually produced embryos are brooded within the colony, before larvae are released. Larvae settle after liberation and metamorphose into an ancestrula.
Like all bryozoans, C. barleei is a suspension feeder. It feeds on small phytoplankton using ciliated tentacles of the lophophore.
Hemispherical brood chambers (ovicells) are immersed within the zooid (endozooidal), with only the rim of the ovicell orifice protruding above the surface of the colony. Ovicells are visible from the colony surface, and embryos are pure white in colour. The larvae of Chartella barleei are non-feeding coronate larvae, which lack a shell and have a densely ciliated belt (the corona) for locomotion.