Neomonoceratina iniqua ( Brady, 1868 )

Chitnarin, Anisong, Forel, Marie-Béatrice & Tepnarong, Prachya, 2023, Holocene ostracods (Crustacea) from a whale-fall excavation site from the Chao Phraya delta, Central Thailand, European Journal of Taxonomy 856 (1), pp. 120-151 : 130-131

Neomonoceratina iniqua ( Brady, 1868)

Fig. 6A–C

Cytherura iniqua Brady 1868: 64 , pl. 8 figs. 3–6.

Trachyleberis? vjetnamica Schneider, 1971: 261 , figs e–f.

Neomonoceratina diptera Hu & Yang, 1975: 108 , pl. 1 figs 19–20.

Cytherura iniqua – Brady 1886: 130, pl. 39 figs 31–33.

Neomonoceratina sp. A – Paik 1977: 42, pl. 2 figs 24–28, pl. 8 fig. 148.

Neomonoceratina iniqua – Zhao & Whatley 1988: 566, pl. 1 figs 7–12; 1989: 171. — Dewi 1993: 60. — Hussain 1998: 4, pl. 1 fig.11 — Al-Jumaily & Al-Sheikhly 1999: 217, fig. 15. — Mostafawi 2003: 56, fig. 6. — Montenegro et al. 2004: pl. 2 fig. 4. — Gopalakrishna et al. 2007: pl. 1 fig. 10. — Fauzielly et al. 2012: fig. 3(6); 2013: fig. 6(10). — Baskar et al. 2013: fig. 3(4). — Hussain & Kalaiyarasi 2013: fig. 11.2(a–b). — Forel 2021: fig. 4d–e. — Tan et al. 2021: fig. 2(7).

Dimensions

L = 0.542 –0.592 millimeters; H = 0.267 –0.292 millimeters, H/L = 0.48–0.50.

Distribution

Modern distribution: Java Sea ( Brady 1868; Dewi 1993, 2000; Fauzielly 2013; Fauzielly et al. 2012, 2013); Iraq ( Al-Jumaily & Al-Sheikhly 1999); east India (e.g., Hussain & Mohan 2001; Hussain et al. 2007); southeast India (e.g., Hussain 1998; Hussain et al. 2004, 2007, 2013a; Baskar et al. 2013; Hussain & Kalaiyarasi 2013); southwest India (e.g., Hussain et al. 2013b; Gopalakrishna et al. 2007); west India (e.g., Bhatia & Kumar 1979); Sri Lanka ( Iwatani et al. 2014); Persian Gulf ( Paik 1977; Mostafawi 2003; Mostafawi et al. 2010); Malaysia (e.g., Zhao & Whatley 1989; Ramlan & Noraswana 2009, 2010); Vietnam ( Tan et al. 2021); Mae Khlong river mouth, north west Gulf of Thailand ( Montenegro et al. 2004); southwestern coast of Peninsular Thailand, Ao Nun, Satun Province, Andaman Sea ( Forel 2021);

Fossil distribution: Bangkok Clay (samples 20SS01A, 02A, 02B, 04B), whale excavation site, Samut Sakhon Province, Thailand, Late Holocene (this work, Fig. 4 ).

Remark s

Neomonoceratina iniqua ( Brady, 1868) is characterized by its reticulate surface with thin muri and polygon fossae, indistinct and short posterodoral rib, long median rib from anterior to posterocentral region, and venterolateral rib terminating into a simple spine. Sexual dimorphism is well expressed with longer and slender male carapaces while female carapaces are shorter and higher. This is the first discovery of the species from Holocene sediments.

Figures

Fig. 6. Holocene ostracods from Samut Sakhon Province, Central Thailand. A–C. Neomonoceratina iniqua (Brady, 1868). A. Valve, male, right lateral view, SUT-20SS-C097. B. Valve, male, left lateral view, SUT- 20SS-C095.C.Valve,male,rightlateralview, SUT-20SS-C093.–D–I.Neomonoceratinarhomboidei(Brady, 1968). D. Carapace, male, right lateral view, SUT-20SS-C113. E. Carapace, male, right lateral view, SUT- 20SS-C120. F. Carapace, female, right lateral view, SUT-20SS-C099.G. Carapace, female, left lateral view, SUT-20SS-C107. H. Carapace, female, dorsal view, SUT-20SS-C114.I. Sieve pores. –J. Neomonoceratina columbiformis Kingma, 1948. Carapace, left lateral view, SUT-20SS-C181. – K–N. Neomonoceratina mediterranea mediterranea (Ruggieri, 1953). K. Carapace, female, right lateral view, SUT-20SS-C167. L. Carapace, female, right lateral view, SUT-20SS-C173. M. Carapace, female, left lateral view, SUT- 20SS-C164. N. Carapace, female, dorsal view, SUT-20SS-C174. – O–T. Neomonoceratina mediterranea malayensis Zhao & Whatley, 1988. O. Carapace, male, right lateral view, SUT-20SS-C159. P. Carapace, male, left lateral view, SUT-20SS-C157. Q. Carapace, male, dorsal view, SUT-20SS-C161. R. Carapace, male, left lateral view, SUT-20SS-C152. S. Carapace, male, left lateral view, SUT-20SS-C141. T. Valve, male, internal view of left valve, SUT-20SS-C160. Scale bars = 1 mm.

Fig. 4. Distribution of Holocene ostracods below and above the whale skeleton level at the whale-fall excavation site in Samut Sakhon Province, north of Gulf of Thailand.