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Primorella
Classification
Phylum:
Bryozoa
Subphylum:
Ectoprocta
Class:
Gymnolaemata
Order:
Cryptostomata
Suborder:
Rhabdomesina
Family:
Rhomboporidae
Formal Genus Name and Reference:
Primorella Romanchuk & KISELEVA, 1968, p. 57
Type Species:
P. polita
Images
(Click to enlarge in a new window)
Fig. 289, 2a-c. *P. polita, PIN 2210/386, a, axial region, zooecial shapes and arrangement; long. sec., X24; b, zooecial arrangement, lamellat profile, stylets; transv. sec., X40; c, apertutal arrangement, Stylet development; tang. sec., X40.
Synonyms
Geographic Distribution
USSR
Age Range
Beginning Stage in Treatise Usage:
U.Carb. (Stephan.)
Beginning International Stage:
Kasimovian
Fraction Up In Beginning Stage:
0
Beginning Date:
307.02
Ending Stage in Treatise Usage:
U.Perm.
Ending International Stage:
Changhsingian
Fraction Up In Ending Stage:
100
Ending Date:
251.9
Description
Zoarium with jointing unknown; branch diameters 1.0 to 1.5 mm, probably varied between bifurcations. Apertural arrangement basically rhombic, somewhat irregular. Metapores unknown. Axial region formed by linear, generally well-defined axis. Zooecial bases weakly inflated; zooecial cross sections polygonal, irregular in endozone. Zooecial divergence approximately 20° to 30°. Zooecial bend rounded. Living chambers generally oriented about 90° to branch surface. Zooecial length 5 to 8 times diameter; longitudinal arrangement of zooecia irregular. Diaphragms scattered. Exozone irregular, wide, ranging to four-fifths branch radius. Lamellar profile broadly V-shaped in exozone. Aktinotostyles abundant, in single or double series in exozone; arising near base of exozone, with diameters relatively constant with growth, parallel to zooecia. [Primorella was originally assigned to the Trepostomata (ROMANCHUK & KISELEVA, 1968), apparently because of overall growth habit. GORYUNOVA (1975) reassigned the genus to the Rhabdomesoidea (Rhabdomesina), noting it differed from Pamirella only in stylet development. Primorella is here included in the Rhabdomesina because of the nature of the axial region, zooecial shape, and development of stylers. It is distinguished on apertural arrangement, zooecial shape and arrangement, development of exozone, and development of aktinotostyles as the only stylet cype.]
References
Museum or Author Information
Classification
Phylum:
Bryozoa
Subphylum:
Ectoprocta
Class:
Gymnolaemata
Order:
Cryptostomata
Suborder:
Rhabdomesina
Family:
Rhomboporidae
Formal Genus Name and Reference:
Primorella Romanchuk & KISELEVA, 1968, p. 57
Type Species:
P. polita
Images
(Click to enlarge in a new window)
Fig. 289, 2a-c. *P. polita, PIN 2210/386, a, axial region, zooecial shapes and arrangement; long. sec., X24; b, zooecial arrangement, lamellat profile, stylets; transv. sec., X40; c, apertutal arrangement, Stylet development; tang. sec., X40.
Synonyms
Geographic Distribution
USSR
Age Range
Beginning Stage in Treatise Usage:
U.Carb. (Stephan.)
Beginning International Stage:
Kasimovian
Fraction Up In Beginning Stage:
0
Beginning Date:
307.02
Ending Stage in Treatise Usage:
U.Perm.
Ending International Stage:
Changhsingian
Fraction Up In Ending Stage:
100
Ending Date:
251.9
Description
Zoarium with jointing unknown; branch diameters 1.0 to 1.5 mm, probably varied between bifurcations. Apertural arrangement basically rhombic, somewhat irregular. Metapores unknown. Axial region formed by linear, generally well-defined axis. Zooecial bases weakly inflated; zooecial cross sections polygonal, irregular in endozone. Zooecial divergence approximately 20° to 30°. Zooecial bend rounded. Living chambers generally oriented about 90° to branch surface. Zooecial length 5 to 8 times diameter; longitudinal arrangement of zooecia irregular. Diaphragms scattered. Exozone irregular, wide, ranging to four-fifths branch radius. Lamellar profile broadly V-shaped in exozone. Aktinotostyles abundant, in single or double series in exozone; arising near base of exozone, with diameters relatively constant with growth, parallel to zooecia. [Primorella was originally assigned to the Trepostomata (ROMANCHUK & KISELEVA, 1968), apparently because of overall growth habit. GORYUNOVA (1975) reassigned the genus to the Rhabdomesoidea (Rhabdomesina), noting it differed from Pamirella only in stylet development. Primorella is here included in the Rhabdomesina because of the nature of the axial region, zooecial shape, and development of stylers. It is distinguished on apertural arrangement, zooecial shape and arrangement, development of exozone, and development of aktinotostyles as the only stylet cype.]