Category: Sachitida

Belongs within: Ischnochitonina. The Chaetopleuridae are a family of chitons known from the Miocene to the present (Smith 1960). Characters (Smith 1960): Valve structure consisting of usual shell layers with addition of well-developed mesostracum. Tegmentum with complicated microstructure and sculpture consisting generally of radial rows of pustules or nodules on end valves and lateral areas of intermediate… Continue reading Chaetopleuridae

Belongs within: Sachitida.Contains: Chelodina, Neoloricata, Solenogastres, Caudofoveata. The Aculifera are an assemblage of molluscs with an external mantle stiffened by spicules or scales. The Polyplacophora, chitons, have a dorsal shell comprised of a series of separate overlapping valves surrounded by a spicular girdle. In modern Aplacophora, the shell is entirely absent but a similarly valvular… Continue reading Aculifera

Belongs within: Ischnochitonidae. The subgenus Stenoradsia of the genus Stenoplax includes species with the insertion plates of intermediate valves multi-slitted. <==Stenoplax (Stenoradsia Carpenter in Dall 1879) [incl. Maugerella Dall 1879]S60 |–S. (*S.) magdalenensis (Hinds 1844)S60 [=Chiton magdalenensisS60, Ischnochiton (S.) magdalenensisO27] |–‘Ischnochiton’ (S.) acrior Carpenter in Pilsbry 1892O27 |–‘Ischnochiton’ (S.) aureotinctus Carpenter 1892O27 |–‘Ischnochiton’ (S.) berryi Dall 1919O27 |–‘Ischnochiton’ (S.) brunneus… Continue reading Stenoplax (Stenoradsia)

Belongs within: Ischnochitonina. Callistochiton is a genus of chitons with a conspicuously sculptured tegmentum found in temperate seas (Smith 1960). Characters (Smith 1960): Tegmentum conspicuously sculptured, central areas smooth in middle, with netted pattern or pitted toward apex, or sculptured throughout with parallel lirae. Insertion plates short, smooth or nearly so, festooned, being curved outward at ribs and… Continue reading Callistochiton

Belongs within: Neoloricata. The Lepidopleuridae are a group of small chitons in which the articulamentum is poorly developed (Smith 1960). Characters (from Smith 1960): Relatively small (less than 5 cm long); valves generally sculptured with granules closely set in lines or quincunx; valve coverage complete; girdle narrow, minutely spiculose or scaly; insertion plates lacking, or… Continue reading Lepidopleuridae

Belongs within: Neoloricata.Contains: Callochiton, Acanthochitona, Notoplax, Mopaliidae, Chaetopleuridae, Callistochiton, Ischnochitonidae, Chitonidae. The Ischnochitonina are a group of chitons, including the greater number of living species, in which the ventral layer of the valves forms a well developed articulamentum (Smith 1960). The Cryptoconchidae, in which the dorsal tegmentum is reduced relative to the articulamentum, have been… Continue reading Ischnochitonina

Belongs within: Ischnochitonina.Contains: Stenoplax (Stenoradsia), Ischnochiton, Lepidozona. The Ischnochitonidae are a group of chitons in which the dorsum of the intermediate valves is divided into distinct lateral and central areas, often by a diagonal rib (Smith 1960). The Lepidochitonidae are a group of chitons in which the valve margins bear distinctly separated apophyses. Articles on… Continue reading Ischnochitonidae

Belongs within: Ischnochitonina.Contains: Mopalia. The Mopaliidae are a group of chitons found in the Pacific Ocean and polar regions characterised by a more or less bristly girdle (Smith 1960). Characters (from Smith 1960): Small to large chitons with tegmentum divided into usual lateral and central areas, sculpture combining radial and longitudinal ribs or lirae that… Continue reading Mopaliidae