Thalamoporella dorothea Guha & Gopikrishna, 2004

Sonar, Mohan A., Pawar, Ravi V. & Wayal, Dyaneshwar V., 2022, Fossil Thalamoporellidae (Bryozoa) from Paleogene-Neogene sediments of western Kachchh, Gujarat, India, Zootaxa 5104 (2), pp. 251-274 : 260-261

Thalamoporella dorothea Guha & Gopikrishna, 2004

( Fig. 9 , Table 6)

Thalamoporella dorothea Guha & Gopikrishna, 2004: 10 , figs 4, 5.

Material examined. GIS/B 0196–0203. Gypseous shale Harudi, Harudi Formation, middle Eocene (Lutetian), 23 ° 31’25” N, 68 ° 41’07” E, elevation 10 m, 13 January 2011, DST project, New Delhi . GIS/B 0204–0210. Waior Limestone, Maniyara Fort Formation, upper Oligocene (Chattian), 23 ° 25’30” N, 68°41’58” E, elevation 6 m, 13 January 2011, DST project, New Delhi .

Description. Colony erect, quadriserial, stem four-sided, dichotomously branching. Autozooids in alternating longitudinal series, more or less elongate-rectangular, cryptocystal margins raised, coarsely granular, slightly tapering proximally. Orifice transversely D-shaped, arched distal margin thick, raised, the proximal rim elevated, weakly concave ( Fig. 9A, B ). Adoral areas narrow, with indistinct tubercles. Two large opesiules, equal, longitudinally oval, adjacent to lateral walls of zooid below proximal orificial rim, polypide tube slightly sunken. Cryptocyst long, narrow, with minute perforations, deeply sunken proximally ( Fig. 9A ). Avicularia and ovicells not observed.

Remarks. The present material conforms to Thalamoporella dorothea Guha & Gopikrishna, 2004 in all essential characters. The species superficially resembles Thalamoporella tewarii Guha & Gopikrishna, 2004 (p. 27, figs 24, 25). Both species have an erect growth form and lack avicularia, but the latter has more zooidal series, and stems expand distally while autozooids are not so narrow and elongate as in T. dorothea . In its erect habit, the present species may be compared with Thalamoporella victoriensis Soule, Soule & Chaney, 1992 , but this species is bilaminar, with broader stems.

Figures

FIGURE 9. Thalamoporella dorothea Guha & Gopikrishna, 2004 (GIS/B 0196). A. General view of a fragment showing autozooids. B. Enlargement of the autozooid, orifice, opesiules and beaded mural rim. C. Close up of the orifice, opesiules and cryptocyst. Scale bars: A, 200 µm; B, 200 µm; C, 100 µm.