° References of the most recent publications

Diagnosis

Last update: February 9, 2003   Extended specimens up to about 140 mm, diameter 0.3 to 1 mm. Colour in life: pink-yellowish. Lophophore horseshoe-shaped, ends sometimes turned medially. Up to 140 tentacles, length 2-2.5 mm . Nephridia with two pseudo-funnels, the anal slightly larger than oral, a descending and ascending branch; nephridiopore opens on anal papilla at anus level. A single giant nerve fibre, on the left side at the level of the attachment of the left lateral mesentery to the body wall, 10-20 µm in diameter. Longitudinal muscle bundles of feathery type, developed into six longitudinal zones and circular musculature with three sphincters (see Silén, 1952); the mean formula and general formula are respectively: 5 | 5 4 | 4 = 18  and  4-5 | 5  4-5 | 3-4 [17-19]   (n= 144 individuals) Sexual reproduction: hermaphroditic, ova freely discharged in the sea-water; males with large, glandular lophophoral organs. Phoronis pallida is embedded vertically in soft sediments, generally sand to muddy sand. Santagata (2002) cites a commensalim within the burrow of the thalassinid shrimp Upogebia pugettensis in False Bay (Washington, USA). Bathymetric range from the upper subtidal to 25 m. Densities up to 74 000 individuals/ m-2. The distribution of Phoronis pallida is represented below on the map. Type-locality: Gullmar Fiord (Sweden) © Christian C. Emig Last update: November 28, 2006

Most recent published diagnoses  Emig C. C., Roldán C. & J. M. Viéitez, 2005. Filo Phoronida. In: Fauna Ibérica, vol. 27. Museo de Ciencias Naturales, CSIC Madrid, p. 19-54 & 180-186 & 223-224. Santagata S., 2004. A waterborne behavioral cue for the actinotroch larva of Phoronis pallida (Phoronida) produced by Upogebia pugettensis (Decapoda: Thalassinidea). Biol. Bull., 207, 103-115. Santagata S., 2002. Structure and metamorphic remodeling of the larval nervous system and musculature of Phoronis pallida (Phoronida). Evolution and Development, 4 (1), 28-42.  Bailey-Brock J. H. & C. C. Emig, 2000. Hawaiian Phoronida (Lophophorata) and their distribution in the Pacific region. Pacific Science, 54 (2), 119-126.  Viétiez J. M., Emig C. C., Rodriguez-Babío C. & A. M. García Carrascosa, 1987. Foronídeos de las costas de la Península Ibérica e Islas Baleares: sistemática, ecología, distribución y estados larvarios. Boletin del Instituto Español de Oceanografia,, 40, 129-133. References on Phoronis pallida