Rectifenestella crassinodata, Ernst & Senowbari-Daryan & Hamedani, 2006

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 : 554

Rectifenestella crassinodata n. sp. ( Fig. 4 F-H, J; Table 9)

HOLOTYPE. — SMF 2113 .

ETYMOLOGY. — The species name is a combination of Latin words “ crassus ” (thick) and “ nodus ” (node), referring to its prominent nodes.

PARATYPES. — 1-5-2, 23-1-1.

TYPE LOCALITY. — Lakaftari, central Iran.

TYPE LEVEL. — Jamal Formation, Middle Permian.

ADDITIONAL MATERIAL EXAMINED. — 1-8, 2-2, 4-15, 7-9, 9-4-4, 23-8.

OCCURRENCE. — Lakaftari: central Iran, Jamal Formation, Middle Permian.

DIAGNOSIS. — Moderately robust reticulated colony with large and widely spaced keel nodes.

DESCRIPTION

Micrometric formula: 13-22/10-16//16-27. Reticulated colonies with straight branches, joined by dissepiments. Bifurcation common. Autozooecia arranged in two alternating rows on branches, becoming three in the place of bifurcation. Apertures circular, usually spaced 2 per length of a fenestrule, containing eight small nodes in peristome shaping it as regular octagons. Shape of fenestrules varying from oval to slightly rectangular. Keel high, carrying single row of large and widely spaced nodes. Internal granular skeleton thick, well developed, continuous with obverse keel, nodes, peristome and across dissepiments. Outer lamellar skeleton thick; no microacanthostyles or striations observed; concave part of the reverse surface forming regular hexagons.

INTERIOR DESCRIPTION

Autozooecia pentagonal in the middle tangential section, 0.09-0.13 mm deep (0.11 mm averagely), and 0.19-0.21 mm long (0.20 mm averagely), with well developed, 0.08-0.10 mm long vestibule; aperture positioned at distal to distal-abaxial end of chamber. Superior hemisepta short; inferior hemisepta absent.

COMPARISON

Rectifenestella crassinodata n. sp. is similar to R. totshanensis (Morozova, 1970) from the Middle Permian (Guadalupian) of SE Mongolia and China, differing in larger and more widely spaced nodes on keel. R. zavodovskyi (Nekhoroshev, 1959) from the Upper Permian of the Northern Ural is also similar, having large nodes, but it has thicker branches – 0.45-0.55 vs. 0.28-0.44 mm in present material. R. pentagonalis (Shulga-Nesterenko, 1936) from the Lower Permian of the Northern Urals is similar but differs in having smaller and more closely spaced nodes on keel.

Figures

FIG. 4. — A-E, Dyscritella leptosa n. sp.; A, SMF 2111, holotype, longitudinal section through the cylindrical colony; B, paratype 23- 6-10, cross section through the cylindrical colony; C, paratype 23-6-10, cross section through the encrusting colony; D, holotype 17-1-4, longitudinal section through the cylindrical colony;E, holotype 17-1-4, tangential section;F-H, J, Rectifenestella crassinodata n. sp.; F, SMF 2113,holotype,tangential section displaying apertures with apertural nodes;G, SMF 2113, holotype,tangential section displaying apertures and carinal nodes; H, 1-5-2, deep tangential section displaying autozooecia; J, 23-1-1, tangential section; I, K, L, Rectifenestella araxensis (Nikiforova,1933) n. comb.; I, 1-4-3, deep tangential section displaying autozooecia;K, 17-1-6, tangential section displaying apertures and carinal nodes; L, 1-4-1, deep tangential section. Scale bars: A, C, K, L, 0.5 mm; B, 1 mm; D, F, 0.2 mm; E, H, I, 0.1 mm; G, 0.25 mm; J, 2 mm