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A feeding zooid in a hydroid colony having an oral opening surrounded by tentacles.

[hydr(a) + Greek anthos, flower.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Zoology) a polyp in a colony of hydrozoan coelenterates that is specialized for feeding rather than reproduction
[C19: from hydra + Greek anthos flower]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈhaɪ drənθ)

any of the asexual feeding polyps in a hydroid colony.
[1870–75; hydr (a) + Greek ánth(os) flower]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
The only local records of freshwater polyps in the country correspond to Cordilophora caspia (Pallas) (Cordero, 1941), in Las Brujas stream near the capital city of Montevideo and to a hydranth of Calpasoma dactylopterum Fuhrmann 1939, casually mentioned by Dioni (1974) as occurring in an artificial pond in Montevideo without further detail.
Hydroid: stolonal, hydranth 1-6 mm high, with very short pedicel, perisarc smooth.
Hydranth ovoid, with 20 to 32 thin tentacles, about 1.4 mm long.
(1978) proposed that increased chloride concentrations tend to produce larger colonies with more tentacles per hydranth in habitats in Texas.
For all samples, we removed one haphazardly chosen hydranth from a colony and placed it on a glass slide.
Since every part of the stem of Tubularia is capable of producing a hydranth the inhibition of basal development is obviously due to the presence of a hydranth or of a developing hydranth at the oral end.
In these juvenile polyps, the cushion-like tissue disappeared into the endoderm of the aboral half, and many digestive gland cells developed in the endoderm of the oral half of the hydranth (Fig.
Surface areas were determined from length and width (average of widths at top and bottom of cell), measured for rectangular hydranth cells, and diameter for circular tentacle cells.
infrastructure and cytochem-istry of glycogen-containing vacuoles in gastrodermal cells in developing hydranths of a hydromedusan coelenterate.
Lovenella gracilis is active only (as indicated by presence of hydranths) from April to October in Virginia (Calder 1990).
The regression-replacement cycle of hydranths of Obelia and Campanularia.