Fossil Thalamoporellidae (Bryozoa) from Paleogene-Neogene sediments of western Kachchh, Gujarat, India
Author
Sonar, Mohan A.
Department of Geology, Government Institute of Science, Aurangabad, Maharashtra, India.
Author
Pawar, Ravi V.
Department of Geology, Government Institute of Science, Aurangabad, Maharashtra, India.
Author
Wayal, Dyaneshwar V.
Department of Geology, Government Institute of Science, Aurangabad, Maharashtra, India.
text
Zootaxa
2022
2022-02-25
5104
2
251
274
journal article
20446
10.11646/zootaxa.5104.2.5
dc85c0df-79ee-4aab-b21d-2df3a61d8ac0
1175-5326
6280839
DE993A29-98B4-4DA0-85CF-9B8D4868A454
Thalamoporella kharinadiensis
Guha & Gopikrishna, 2004
(
Fig. 11
,
Table 8
)
Thalamoporella kharinadiensis
Guha & Gopikrishna, 2004: 23
, figs 20, 21.
Material examined.
GIS/B 0231–0270.
Yellowish
limestone west of
Haripar
,
Kharinadi Formation
,
lower Miocene
(Aquitanian),
23°22’08’’ N
,
68° 49’40’’ E
,
elevation
20 m
,
14 January 2011
, DST project, New
Delhi
.
Description.
Colony erect, bilaminar. Autozooids arranged quincuncially in alternating longitudinal series, rectangular, bordered by indistinct, raised, smooth autozooidal borders. Orifices subcircular, a little wider than long, strongly arched distally with a concave proximal margin (
Fig. 11A, B
). Cryptocyst shallow, smooth, gently sloping towards opesiular region. Adoral area narrow lacking tubercles. Opesiules large, rounded, unequal, deeply sunken, adjacent to lateral walls proximal to orifice. Avicularia at bifurcation of rows,
c.
75% of autozooidal length, vicarious, elongate, straight, with rounded rostrum directed distally; foramen somewhat elongate-pyriform in eroded present material,
c.
80% of avicularian length, cryptocyst little preserved proximally, smooth (
Fig. 11B
). Ovicells not observed.
Remarks.
The present material agrees with
T. kharinadiensis
Guha & Gopikrishna, 2004
, but the preservation is poor, reflected in the details of the avicularium and apparent absence of pores in the cryptocyst. Additionally, most of the autozooids in a colony show anomalous growth, i.e. incomplete cryptocysts, that might reflect growth in a low pH setting.