acorn worm


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acorn worm

a hemichordate, one of the three groups of invertebrate chordates collectively referred to as PROTOCHORDATES.
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The spawning and early development of the Hawaiian acorn worm (hemichordate).
Hemichordates are a type of marine animal split into two groups: the acorn worm, which live in burrows, and the pterobranchs, which live in a tubular structure anchored to the ocean floor.
Allapasus isidis is the name given to a white acorn worm which was named after the NERC-owned remotely operated vehicle, ROV Isis, which collected the specimens from the ocean.
The median intensity, ranging from 2.0 to 7.0 parasites per infected acorn worm, also showed a similar trend with the mean intensities observed between each month (Table 1).
This result suggests that early hemichordates were enteropneust-like, with pterobranchs arising from acorn worm ancestors (Rychel and Swalla, 2007; Brown et al., 2008; Cannon et at., 2009; Peterson et al., 2013).
In the autumn of 2011, a single acorn worm was recovered from a Sigsbee trawl during cruise 59 of the RN Akademik Mstislav Keldysh.
Reports are also rare on the abundances of these groups and acorn worms for the Eastern Tropical Pacific region.
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.
The deuterostome super-phylum includes three other major animal body architectures: the phyla Chordata (including Humans), Echinodermata (starfish and sea urchins) and Hemichordata (acorn worms).
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.
("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?