Polypora soyanensis Morozova, 1970

Ernst, Andrej, Senowbari-Daryan, Baba & Hamedani, Ali, 2006, Middle Permian Bryozoa from the Lakaftari area, northeast of Esfahan (central Iran), Geodiversitas 28 (4), pp. 543-590 : 568-569

Polypora soyanensis Morozova, 1970 ( Fig. 9 L-R; Table 23)

Polypora soyanensis Morozova, 1970a: 211 , 212, pl. 48,

fig. 3, pl. 49, fig. 2. — Sakagami 1980: 278, 279, pl. 32, fig. 6; 1999: 97, 98, pl. 24, fig. 3.

Polypora sp. cf. P. orientalis – Sakagami in Yanagida 1988: pl. 21, figs 2, 3.

HOLOTYPE. — No. 1692/168, PIN; River Soyana, Arkhangelsk region, Russian Platform. Middle Permian, Lower Kazanian Substage.

MATERIAL EXAMINED. — 1-8, 4-5, 4-6-1, 4-7-2, 4-8-4, 4-18, 5-4-1, 5-8-2, 7-3-1, 7-3-2, 7-5-3, 7-7-1, 7-9-1, 23-6-1, 23-6(3-4), 23-7, 23-8, 24-1, 24-5, 25-1-2.

OCCURRENCE. — Russian Platform, Middle Permian, Lower Kazanian Substage. Thailand, Permian. Abadeh region: central Iran, Upper Permian. Lakaftari: central Iran, Jamal Formation, Middle Permian.

DESCRIPTION

Micrometric formula: 11-14/10-15//17-20.5. Reticulated colonies with straight branches, joined by dissepiments. Bifurcation common. Autozooecia arranged in 3-4 alternating rows on branches, becoming 5 in the place of bifurcation, and 2-3 after the bifurcation. Apertures circular, spaced 2-3 per fenestrule length; 2-4 small nodes developed in peristome. Shape of fenestrules varying from oval to rectangular. Keels absent. Nodes small to moderately large, arranged in regular rows between apertures on the obverse colony surface, displaying radial arrangement of rods. Internal granular skeleton thick, well developed, continuous with nodes, rods, peristome and across dissepiments. Outer lamellar skeleton moderately thick, containing abundant rods 5-6 µm in diameter. Ovicells occurring occasionally, shaped as spherical chambers attached at distal part of apertures, reaching 0.14 mm in diameter.

INTERIOR DESCRIPTION

Autozooecia rhombic in the middle tangential section, irregularly shaped in the place of bifurcation; high and short in longitudinal section, with well developed vestibule; elongate to branch length; aperture positioned at distal to distal-abaxial end of chamber. Hemisepta absent.

COMPARISON

Polypora soyanensis is similar to P. magnicava from the Middle Permian (Lower Kazanian) of the Archangelsk

region (Russian plate) ( Morozova 1970a), differing from the latter in smaller fenestrules and wider dissepiments. Polypora tubulosa Nikiforova, 1933 from the Middle Permian (Gnishik Horizon, Guadalupian) of Transcaucasia, is also similar to P. soyanensis , differing in thicker branches and larger fenestrules.

Figures

FIG. 9. — A-C, E, Mackinneyella dzhulfensis (Morozova,1965);A, 13a, deep tangential section;B, 12-2-3,tangential section; C, 12-2-3, deep tangential section; E, 12-2-3, tangential section showing apertures and nodes; D, F-K, Mackinneyella robustiformis (Morozova, 1965); D, 4-18-2, deep tangential section; F, 4-18-2, tangential section showing apertures with apertural nodes; G, 4-18-2, tangential section of the branch; H, 4-18-2, deep tangential section showing autozooecial chambers; I, 19-4-10, cross section of the branch; J, 4-18-2, thin section showing reverse surface with microacanthostyles and hyaline rods; K, 19-4-10, cross section of the branch showing outer laminated skeleton with microacanthostyles; L-R, Polypora soyanensis Morozova, 1970; L, 23-6-3, tangential section; M, 18-1-6, tangential section; N, 1-8-2, tangential section; O, 18-1-6, cross section; P, 18-1-6, tangential section showing ovicell; Q, 23-6-3, tangential section showing radial structure of a node; R, 23-6-3, tangential section showing apertures and nodes. Scale bars: A, L, M, 1 mm; B, D, 2 mm; C, E, G-I, O, 0.25 mm; F, 0.2 mm; J, K, P-R, 0.1 mm; N, 0.5 mm.