Pseudoendophyllum sp.

Denayer, Julien, 2016, Rugose corals across the Devonian-Carboniferous boundary in NW Turkey, Acta Palaeontologica Polonica 61 (1), pp. 51-70 : 60-61

Pseudoendophyllum sp.

Fig. 5N–Q .

2013 cf. Endophyllum sp. ; Denayer 2013: 36: 1D.

Material.—Fragments of two small colonies (5TS, 1 LS) from Dallıca (Bartın), uppermost Famennian.

Description.—The colonies are small (10 cm in diameter), fasciculate to sub-cerioid ( Fig. 5N ). The corallites are cylindrical to sub-prismatic. Their mean width is 16 mm and their tabularium diameter is 9 mm in average (maximum 12 mm). There are 33 septa of each order (maximum 36). The major septa are long but do not reach the centre of the tabularium where a free zone of 1–3 mm large is usually present. They are sinuous or zig-zag, often thick at the base and sometimes up to the tabularium. The cardinal septum is short; the cardinal-lateral septa are also shorter and edge the opened cardinal fossula. The minor septa are long (more than half the length of the major) and enter into the tabularium. They are sinuous and thinner than the major. Some are contraclinant. In the outer part of the dissepimentarium, the major septa appear as septal crests on the wall or the lonsdaleoid dissepiments. All the septa are intercepted by first order (1–7 rows) and second order (3–5 rows) lonsdaleoid dissepiments. The interseptal dissepiments are concentric, V-shaped and herringbone. The wall is thin and regular but usually eroded. In longitudinal section, the tabulae are complete, mesa-shaped or domed, some are depressed axially ( Fig. 5Q ). The lonsdaleoid dissepiments are 1.5–3 mm long and 0.5 mm high. They are flat and gently inclined in the outer part of the dissepimentarium but smaller (1 mm) and more inclined (60–70°) near the tabularium. The inner row is vertical. There are 12–14 tabulae and up to 24 dissepiments per centimetre.

The increase is lateral and non-parricidal. The offsets appear in the peripheral part of the dissepimentarium. The smallest offsets observed are already cylindrical, 3–4 mm in diameter and have less than 20 short sinuous septa ( Fig. 5P 1 ). The lonsdaleoid dissepiments appear where corallites reach 4 mm in diameter. Unfortunately, the limited material prevents any blastogenic study of this species.

Remarks.—The Famennian species of Pseudoendophyllum described by Berkowski (2002) are cerioid but the Turkish colonies are fasciculate to sub-cerioid. Two hypotheses can explain this habitus. (i) The colonies are really fasciculate and the present specimen might deserve a distinct generic name. This view was supported by Berkowski (2002) in his review of the present genus as he pointed out the bilateral septal arrangement in some specimens. (ii) The fasciculate habit is due to an effect of sedimentation as documented in cerioid colonies of the genera Lithostrotion, Hexagonaria or Phillipsastrea ( Scrutton 1998) . This second hypothesis is supported by cauliflower-shaped stromatoporoid, occurring in the same horizon than Pseudoendophyllum colonies, both witnessing irregular or seasonal sedimentation. In that sense, the attribution of the Turkish specimens to Pseudoendophyllum is consequently acceptable.

Pseudoendophyllum sp. was collected in stromatoporoid beds in the Dallıca section (Bartın). The foraminifer assemblage is poor but the occurrence of Avesnella indicates the lower part of the Strunian (DFZ5–6 biozones of Poty et al. 2006).

Figures

Fig. 5. Cyathophylline Campophyllum flexuosum (Goldfuss, 1826) (A–M) and hetophylline Pseudoendophyllum sp. (N–Q) corals from the uppermost → Famennian (Strunian) of Zonguldak and Bartin areas, Topulca (A, B, D–I, K), Esenpınar (C, J), Gökgöl (L, M), and Dallıca (N–Q) sections, Turkey. A. ET.11.16.b, TS. B. ET.11.17.I, TS. C. EV.3.2, TS. D. ET.11.16.V’, TS. E. ET.11.16.b, TS. F. ET.11.16.IV.b, TS. G. ET.11.18, TS. H. ET.11.18, TS. I. ET.11.13.II.a, TS. J. EV.3.5, TS (J1), LS (J2). K. ET.11.16.V, TS. L. G.3.17.I, LS. M. G.3.15, TS, close-up view of the dissepimentarium. N. D.2.1.II, TS. O. D.2.4.I, TS. P. D.2.2.I.a, successive TS (P1, P2). Q. D.2.2.I.b, LS. Scale bar 5 mm for all specimens except D, 2.5 mm and M, 3.75 mm.

Fig. 1. A. General structural map of Turkey (modified after Görür and Tüysüz 2001; Moix et al. 2008; Okay 2008). CCAC, Central Anatolian Crystalline Complex; EAAC, East Anatolian Accretionnary Complex (Sanadaj-Sirjan Block); Lycian Np., Lycian Nappes. B. Geological map of the Istanbul- Zonguldak Zone (modified after Okay et al. 2006) with the position of the Zonguldak and Bartın areas. C. Simplified geological map of the Zonguldak area (redrawn after Hoşgörmez 2007 and Charles 1933) with the location of the sampled sections (G, Gökgöl section). D. Simplified geological map of the Bartın area (redrawn after Tokay 1954) with the location of the sampled sections (T, Topluca section; D, Dallıca section; E, Esenpınar section).