Polypora, M'Coy, 1844

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 : 570

Polypora aff. anshunensis Yang & Lu, 1980 ( Fig. 10 K-O; Table 26)

Polypora tuberculifera anshunensis Yang & Lu, 1980: 469 , pl. 1, fig. 4.

MATERIAL EXAMINED. — 25-3-1.

OCCURRENCE. — Lakaftari: central Iran, Jamal Formation, Middle Permian. China, Upper Permian ( Yang & Lu 1980).

DESCRIPTION

Micrometric formula: 10-13/10-11//17. Reticulated colonies with straight branches, joined by relatively thin dissepiments. Bifurcation common. Autozooecia arranged in 3-4 alternating rows on branches, becoming 5 at the site of bifurcation. Apertures circular, spaced 3-4 per length of a fenestrule; 2-4 small nodes developed in peristome. Shape of fenestrules varying from oval to rectangular. Keels absent. Nodes moderately large, arranged in regular rows between apertures on the obverse colony surface, displaying radial arrangement of rods. Internal granular skeleton moderately thick, well developed, continuous with nodes, rods, peristome and across dissepiments. Outer lamellar skeleton moderately thick, containing abundant rods 5-6 µm in diameter.

INTERIOR DESCRIPTION

Autozooecia rhombic to hexagonal in the middle tangential section; high and short in longitudinal

section, with well developed vestibule; elongate to branch length; aperture positioned at distal to distalabaxial end of chamber. Hemisepta absent.

COMPARISON

The investigated material is similar to the subspecies Polypora tuberculifera anshunensis from the Upper Permian of China, regarded here as a separate species. The present material differs only in minor details – slightly thinner branches, wider fenestrules. Polypora magnicava from the Middle Permian of the Russian Platform ( Morozova 1970a) is also similar to the present material differing in having thicker branches (0.64 vs. 0.50 mm averagely in present specimen).

Figures

FIG. 10. — A-F, Polypora darashamensis Nikiforova,1933; A, 21-2, tangential section showing aperture with apertural nodes; B, 21-2, tangential section showing aperture with apertural nodes and high peristome;C, 21-2,tangential section showing aperture with apertural nodes and nodes on the colony surface; D, 21-2, deep tangential section; E, 21-2, tangential section showing apertures and nodes on the colony surface; F, 21-2, deep tangential section showing autozooecial chambers;G-J, Polypora magnicava Morozova, 1970; G, I, 19-1, tangential section; H, 19-1, tangential section showing aperture with apertural nodes and nodes on the colony surface; J, 19-1, cross section of the branch; K-O, Polypora aff.anshunensis Yang & Lu, 1980;K, 25-3-1,tangential section;L, M, 25-3-1, cross section; N, 25-3-1, tangential section showing apertures with apertural nodes; O, 25-3-1, deep tangential section;P, Polypora sinokoninckiana Yang & Lu, 1962, 1-3-4, tangential section. Scale bars: A-C, H, N, 0.1 mm; D, G, K, M, P, 1 mm; E, F, I, J, L, O, 0.5 mm.