1) Animal order 2) Order aplacophora 3) Order solenogastres 4) Solenogastres 1) Solenogastres 
Neomeniomorpha (Solenogastres) 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 (Chaetodermomor...
• (n. pl.) A division of Amphineura in which the body is naked or covered with slender spines or setae, but is without shelly plates.
(from the article `mollusk`) ...separate; development includes spiral cleavage and a primitively lecithotrophic trochus larva; about 50,000 marine, limnic, and terrestrial ...
Ap`la·coph'o·ra noun plural [ New Latin , from Greek 
Aplacophora is an order of the Amphineura class of molluscs.