Streblotrypa (Streblascopora) marmionensis (Etheridge, 1926)

Ernst, Andrej, 2016, Bryozoan fauna from the Permian (Artinskian-Kungurian) Zhongba Formation of southwestern Tibet, Palaeontologia Electronica (1946) 51 (9), pp. 1-59 : 30-32

Streblotrypa (Streblascopora) marmionensis (Etheridge, 1926)

Figures 13.9 , 14.1-3 ; Table 18

1926 Streblotrypa marmionensis Etheridge in Bretnall, p. 22, pl. 1, fig. 1, pl. 2, fig. 3.

1931 Streblotrypa marmionensis Etheridge, 1926 ; Hosking, p. 14, pl. 6, fig. 1, text-fig. 1.

1944 Streblotrypa marmionensis Etheridge, 1926 ; Crockford, p. 168-169, pl. 5, figs. 10-11, text-figs. 34-37.

1957 Streblotrypa marmionensis Etheridge, 1926 ; Crockford, p. 80.

1966? Streblascopora cf. marmionensis (Etheridge, 1926) ; Sakagami, p. 166-167, pl. 6, fig. 11.

1983 Streblascopora cf. marmionensis (Etheridge, 1926) ; Yang and Lu, p. 291, pl. 2, fig. 6, pl. 4, figs. 8-9.

?1970 Streblascopora marmionensis (Etheridge, 1926) ; Morozova, p. 151-152, pl. 28, fig. 1.

1971 Streblascopora marmionensis (Etheridge, 1926) ; Termier and Termier, p. 24 (pars.), pl. 9, figs. 1-3, non 4-5.

1975 Streblascopora marmionensis (Etheridge, 1926) ; Gorjunova, p. 65, pl. 9, fig. 1.

1991 Streblascopora marmionensis (Etheridge, 1926) ; Xia, p. 184-185, pl. 5, figs. 7-10.

2008 Streblascopora marmionensis (Etheridge, 1926) ; Ernst, Weidlich and Schäfer, p. 694, figs. 8.10-8.11, 8.13.

2013 Streblascopora marmionensis (Etheridge, 1926) ; Ernst and Gorgij, p. 298, figs. 13d-h.

Material. SMF 23.144– SMF 23.151.

Description. Branched colonies, 1.00– 1.55 mm in diameter, with 0.14–0.26 mm wide exozones and 0.65–1.15 mm wide endozones. Axial bundle 0.26– 0.54 mm in diameter. Axial zooecia arranged in 5– 6 rows, 0.05–0.08 mm in diameter. Autozooecia budding from the axial bundle, having long inflated proximal parts, rounded to polygonal in transverse section in the endozone. Autozooecial apertures oval, arranged in regular diagonal rows. Inferior hemisepta present. Terminal diaphragms common. Metazooecia small, oval to rounded, 8–10 of them arranged in 2–3 rows between apertures. Autozooecial walls laminated, 0.005 –0.010 mm thick in endozone.

Remarks. Streblotrypa (Streblascopora) marmionensis (Etheridge, 1926) differs from S. (S.) germana ( Bassler, 1929) in possessing hemisepta, thicker branches and a larger diameter of the axial bundle. Streblotrypa (Streblascopora) marmionensis is similar to S. (S.) erecta Baranova, 1960a from the Lower Permian of northeastern Russia, but differs from it by more metazooecia between autozooecial apertures (8–10 vs. 6–9). Streblotrypa (Streblascopora) marmionensis differs from S. (S.) tscharlakensis Trizna, 1950 from the Lower Permian (Sakmarian–Artinskian) of Urals in having a larger number of axial zooecia in the axial bundle and a larger number of metazooecia between autozooecial apertures (8–10 vs. 6–8).

Occurrence. Lower Permian (Noonkanbah Series and Liveringa Formation); Western Australia. Lower Permian; Pamir, Tajikistan. Aseelah Unit, Saal Formation (Lower–?Middle Permian); Batain Coast (eastern Oman). Chili Formation, Lower Permian (Sakmarian–Artinskian); Kalmard area, central Iran. Zhongba Formation, Permian (upper Cisuralian–Guadalupian); Zhongba area of southwestern Tibet.

Figures

FIGURE 13. Thin section photographs of Streblotrypa (Streblotrypa) parviformis n. sp., paratype SMF 23.260 (1) and paratype SMF 23.256 (2 and 3); Streblotrypa (Streblascopora) delicatula Sakagami, 1961, SMF 23.205 (4, 6, and 7), SMF 23.206 (5), and SMF 23.143 (8); and Streblotrypa (Streblascopora) marmionensis (Etheridge, 1926), SMF 23.145 (9). 1 and 8, branch transverse section; 2, 3, 5, and 9, longitudinal section; 4, branch oblique section; and 6 and 7, tangential section.

FIGURE 14. Thin section photographs of Streblotrypa (Streblascopora) marmionensis (Etheridge, 1926), SMF 23.145 (1 and 2), and SMF 23.148 (3); and Rhabdomeson bretnalli Crockford, 1957, SMF 23.155 (4–6) and SMF 23.157 (7–9). 1, longitudinal section; 2 and 7, tangential section; 3 and 4, branch transverse section; and 5, 6, 8 and 9; branch oblique section.