What is the foot of class aplacophora?
Class Aplacophora includes worm-like animals with no shell and a rudimentary body structure. Members of class Polyplacophora are better known as “chitons;” these molluscs have a large foot on the ventral side and a shell composed of eight hard plates on the dorsal side.
Is Aplacophora extinct?
Aplacophora /æpləˈkɒfərə/ is a presumably paraphyletic taxon. This is a class of small, deep-water, exclusively benthic, marine molluscs found in all oceans of the world. All known modern forms are shell-less: only some extinct primitive forms possessed valves.
Where are Aplacophora found?
mainly lives in oceans, seas, or other bodies of salt water.
Do Aplacophora have a shell?
Aplacophora is a relatively small group of molluscs that are characterized by their lack of shells and worm-like appearance. Instead of a shell, their mantle secretes tiny calcareous spicules which give them a beautiful shine. There are only about 320 species of these exclusively marine molluscs.
Is Radula present in Aplacophora?
Condition of Typical Molluscan Characteristics in Aplacophora: Radula (a rasping “tongue” with chitinous teeth) = Absent or present.
What are the 4 major groups of living mollusks?
The major classes of living mollusks include gastropods, bivalves, and cephalopods (Figure below).
Is a jellyfish a mollusk?
question_answer Answers(2) Ans: Phylum mollusca include soft bodied animals with hard shell Eg: snails, octopus, mussels, oysters. Phylum Coelenterata contain special structure called coelenteron where the food digested.It include jelly fish and sea anemones.
How do Aplacophora eat?
The radula is used to scrape bits of food off rocks and other hard surfaces. In most mollusks, the radula is ribbonlike in shape but not in aplacophorans. Their radulas are part of their gut. The mucus smoothes the way for the aplacophoran as it glides over the track.
What were the ancient molluscs called?
The most ancient molluscs alive today are the so-called aplacophorans, Caudofoveata and Solenogastres.
What is a mollusk without a shell called?
Mollusks without shells include squid, banana slugs, and octopi.
Which Mollusca is called tusk shell?
scaphopoda
The scaphopoda. The Scaphopoda are a distinctive group of molluscs commonly known as the “tusk shells” because their shells are conical and slightly curved to the dorsal side, making the shells look like tiny tusks (see the photos below).
What are 4 examples of bivalves?
They include the clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater.
What is the meaning of the word Aplacophora?
Etymology: [NL., fr. Gr. ‘a priv. + a flat cake + fe`rein to bear.] Aplacophora is a monophyletic group of small, deep-water, exclusively benthic, marine mollusks found in all oceans of the world. All known modern forms are shell-less: only some extinct primitive forms possessed valves.
Are there any shells in the Aplacophora group?
Aplacophora. Aplacophora is a monophyletic group of small, deep-water, exclusively benthic, marine molluscs found in all oceans of the world. All known modern forms are shell-less: only some extinct primitive forms possessed valves. The group comprises the two clades Solenogastres (Neomeniomorpha) and Caudofoveata (Chaetodermomorpha),…
Who was the first person to discover the aplacophoran?
Aplacophorans were first discovered by a Swedish naturalist in 1841. At first they were thought to be related sea cucumbers (Echinodermata). Not until 1875 were they properly recognized as mollusks.
What do Aplacophorans have in common with chitons?
Aplacophorans have little in common with chitons (small armor-plated mollusks), although in the past the two groups were placed together in the class Amphineura. Aplacophorans, which are also called solenogasters, are worm-shaped mollusks covered with spicules or sharp needle-like projections.
