Fabifenestella vediensis ( Morozova, 1965 ) 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 : 562-563

Fabifenestella vediensis ( Morozova, 1965) n. comb. ( Fig. 7 D-H; Table 17)

Fenestella vediensis Morozova, 1965: 190 , pl. 27, fig. 2; 1970a: 174, 175, pl. 25, fig. 4.

HOLOTYPE. — No. 1613/155, PIN; River Vedi , Armenia, Transcaucasia (Nakhichevan); Gnishik Horizon , Middle Permian, Murgabian (= Wordian).

MATERIAL EXAMINED. — 4-5-5, 4-5-6, 4-11, 4-12, 4- 15, 6-1, 7-2, 7-3-7, 7-3-8, 7-5, 7-9, 10-2(b), 12-2-2, 21-1-1, 23-2, 24-1, 24-4, 25-2, 25-12.

OCCURRENCE. — Transcaucasia (Nakhichevan); Gnishik Horizon, Middle Permian, Murgabian (= Wordian). Lakaftari: central Iran, Jamal Formation, Middle Permian.

DESCRIPTION

Micrometric formula: 19.5-25/17.5-20//17.5- 20.5. Reticulated funnel-shaped colonies up to 20 cm high, consisting of straight branches, joined by thin dissepiments. Bifurcation common. Autozooecia arranged in 2 alternating rows on branches. Apertures circular, spaced 2 per length of a fenestrule. Shape of fenestrules varying from oval to slightly rectangular, becoming irregular in places of projection of ovicells. Keel low, carrying two alternating rows of small regularly spaced nodes. Internal granular skeleton thin, continuous with obverse keel, nodes, rods, peristome and across dissepiments. Outer lamellar skeleton moderately thick, containing abundant rods 5-6 µm in diameter. Abundant microacanthostyles on the reverse surface, irregularly spaced, having distinct hyaline cores and dark laminated sheaths, 10-25 µm in diameter. Ovicells spherical chambers, attached at apertures and projecting in neighbouring fenestrules, 0.18 mm in diameter.

INTERIOR DESCRIPTION

Autozooecia rectangular to bean-shaped in the middle tangential section, low and elongated, with well developed vestibule; aperture positioned at distal to distal-abaxial end of chamber. Superior hemisepta long; inferior hemisepta long, low, separating the proximal third of the chamber.

COMPARISON

Fabifenestella vediensis n. comb. is similar to F. thaiensis ( Sakagami, 1966) from the Lower Permian of Peninsular Thailand. The latter one has thinner branches (0.29-0.32 vs. 0.24-0.41 mm in F. vediensis n. comb.), and longer fenestrules (0.56-0.72 vs. 0.34-0.48 in F. vediensis n. comb.).

REMARK

Fenestella vediensis is placed in the genus Fabifenestella because of its bean-shaped autozooecial chambers in the middle tangential section with both superior and inferior hemisepta, and presence of two rows of alternating nodes on the keel ( Morozova 1974: 60).

Figures

FIG. 7. — A-C, Fabifenestella jabiensis (Waagen & Pichl, 1885); A, 10-1-2, tangential section of the keel showing nodes of different sizes; B, 4-15-3, deep tangential section showing bases of autozooecial chambers with inferior hemisepta (arrow: hemisepta); C, 4- 15-2, deep oblique tangential section showing autozooecial chambers with long superior hemisepta; D-H, Fabifenestella vediensis (Morozova, 1965) n. comb.; D, 6-1, fragment of the funnel-shaped colony; E, 12-2-2, tangential section; F, 7-3-7, tangential section showing ovicells; G, 7-3-7, tangential section of the fenestrule with ovicell; H, 4-5-6, deep tangential section showing inferior hemisepta; I-M, Septopora flabellata Nikiforova, 1933; I, 20-2-5, tangential section showing carinal nods; J, 20-2-5, thin section of the reverse surface showing nods, microacanthostyles and cyclozooecia; K, 1-7-3, deep tangential section; L, 1-7-2, tangential section showing apertures, carinal nods and cyclozooecia; M, 4-12, fragment of the funnel-shaped colony. Scale bars: A, B, E, 0.25 mm; C, G, H, 0.1 mm; D, M, 10 mm; F, L, 0.5 mm, I-K, 1 mm.