acorn worm

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Related to acorn worms: Hemichordata, Lancelets

acorn worm

n.
Any of a class (Enteropneusta) of hemichordate, wormlike animals that inhabit intertidal areas and soft marine sediments and have an acorn-shaped proboscis.
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.

acorn worm

n
(Animals) any of various small burrowing marine animals of the genus Balanoglossus and related genera, having an elongated wormlike body with an acorn-shaped eversible proboscis at the head end: subphylum Hemichordata (hemichordates)
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

a′corn worm`


n.
any wormlike marine animal of the phylum Hemichordata, having gill slits and an acorn-shaped proboscis and collar.
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 ?
Indirect-developing acorn worms begin life as planktonic, feeding, tornaria larvae that can remain in the water column for up to 300 days (Hadfield, 1978; Nielsen and Hay-Schmidt, 2007).
There are acorn worms and before you start dismissing worms as inferior and primitive then consider that the acorn worms are classified with us humans in the Phylum Chordata -- chordates like us.
Vargas (1987, 1988) also listed the presence of peanut worms (Sipuncula), Glottidia audebarti (Broderip, 1835) lamp shells (Brachiopoda) and acorn worms (Enteropneusta).
The DNA of two acorn worms from Hawaii were compared with those of 32 species, including humans.
Craniata, or "vertebrates" for example, are given the same weight as lineage containing acorn worms. While this serves to illuminate the diversity of the animal kingdom it also underscores how many similarities all life shares.
Christopher Cameron of the University of Montreal's Department of Biological Sciences and his colleagues have confirmed that Spartobranchus tenuis is a member of the acorn worms group, which are seldom-seen animals that thrive today in the fine sands, and mud of shallow and deeper waters.
Enteropneusts - or acorn worms - are marine animals closely related to starfish and sea urchins.
Yoda purpurata -- to be exact -- is the name now given by a University of Aberdeen-led team of scientists to one of three new species of deep sea acorn worms or Enteropneusts discovered 2,500m or around 1.5 miles below the surface of the Atlantic Ocean.
("Ever heard of acorn worms or leafy sea dragons?" "How about thermoacidophiles?" or "Check out water bears!" "Do you know about lichens, or Welmtschia?") Also, do you want to inspire and challenge students with an automatic "A" for anyone who can identify an organism you've never encountered?
In preliminary studies, Shu Degan of Xian Northwest University places Yunnanozoon in another phylum, the hemichordates, which includes the modern acorn worms.
Acorn worms (Enteropneusta), a solitary class of hemichordates, are marine vermiform invertebrates that generally live concealed in burrows (Hyman, 1959).