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Songiella
From Williams et al., 2017:
[Songiella, Sun Xuekun, 1994, p. 84; Emendation: Xu Jinli et al., 1997, p. 58.
Type species: as Bipolaribucina huanghuaensis, Jiabo, 1978 (pl.29, fig.9)]
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Original description: [Sun Xuekun, 1994]:
Diagnosis:
Cysts chorate, body ellipsoidal to subrectangular. Processes membranous or broad trumpet-like; paracingular processes absent; process-free area between pre-and postcingular processes relatively wide.
Archeopyle apical.
Remarks:
Songiella differs from Kaiwaradinium Wilson 1978, which also has an ellipsoidal central body and a relatively wide process-free area between pre- and postcingular processes, in having membranous processes rather than hollow, tabular processes. It differs from Oligosphaeridium in its membranous processes, more elongate body and wider process-free area. Distatodinium is similar to the present genus in having elongate ellipsoidal body and lacking processes in paracingular area, but the process morphology of the two genera is quite different. Song Zi-chen et al. (1978) erected a genus, Bipolaribucina Jiabo, to include those ellipsoidal chorate cysts whose processes are tabular or baculate and confined to the polar areas. Six species, B. conicosa, B. huanghuaensis, B. liaoningensis, B. oblongata, B. paradoxa and B. tianjinensis were established at the same time. The re-examination of the descriptions and illustrations of Song et al. (1978) indicates that this genus may be a big sac and contain cysts of different genera. In the analyses of fossil dinoflagellate taxa by Chinese authors, 1978-1984, Chen et al. (1988) proposed that Bipolaribucina was the junior synonym of Distatodinium. Thus, the type species of Bipolaribucina, B. paradoxa, was reattributed to Distatodinium as D. paradoxum and the other species of the genus were included in genus Impletosphaeridium. I agree with the re-attribution by Chen et al (1988) of most of the species in Bipolaribucina but do not agree to them in the treatment of B. huaghuensis. Since the process morphology of B. huanghuaensis is remarkably different from that of Impletosphaeridium, cysts of this species should represent a distinct dinoflagellate genus rather than belong to Impletosphaeridium. Considering that the type species of Bipolaribucina was transferred to Distatodinium and the generic description of the former genus is not favorably in accordance with the morphology of B. huanghuanses, I propose herein a new generic name, Songiella, for cysts originally described as B. huanghuaensis.
[Songiella, Sun Xuekun, 1994, p. 84; Emendation: Xu Jinli et al., 1997, p. 58.
Type species: as Bipolaribucina huanghuaensis, Jiabo, 1978 (pl.29, fig.9)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Sun Xuekun, 1994]:
Diagnosis:
Cysts chorate, body ellipsoidal to subrectangular. Processes membranous or broad trumpet-like; paracingular processes absent; process-free area between pre-and postcingular processes relatively wide.
Archeopyle apical.
Remarks:
Songiella differs from Kaiwaradinium Wilson 1978, which also has an ellipsoidal central body and a relatively wide process-free area between pre- and postcingular processes, in having membranous processes rather than hollow, tabular processes. It differs from Oligosphaeridium in its membranous processes, more elongate body and wider process-free area. Distatodinium is similar to the present genus in having elongate ellipsoidal body and lacking processes in paracingular area, but the process morphology of the two genera is quite different. Song Zi-chen et al. (1978) erected a genus, Bipolaribucina Jiabo, to include those ellipsoidal chorate cysts whose processes are tabular or baculate and confined to the polar areas. Six species, B. conicosa, B. huanghuaensis, B. liaoningensis, B. oblongata, B. paradoxa and B. tianjinensis were established at the same time. The re-examination of the descriptions and illustrations of Song et al. (1978) indicates that this genus may be a big sac and contain cysts of different genera. In the analyses of fossil dinoflagellate taxa by Chinese authors, 1978-1984, Chen et al. (1988) proposed that Bipolaribucina was the junior synonym of Distatodinium. Thus, the type species of Bipolaribucina, B. paradoxa, was reattributed to Distatodinium as D. paradoxum and the other species of the genus were included in genus Impletosphaeridium. I agree with the re-attribution by Chen et al (1988) of most of the species in Bipolaribucina but do not agree to them in the treatment of B. huaghuensis. Since the process morphology of B. huanghuaensis is remarkably different from that of Impletosphaeridium, cysts of this species should represent a distinct dinoflagellate genus rather than belong to Impletosphaeridium. Considering that the type species of Bipolaribucina was transferred to Distatodinium and the generic description of the former genus is not favorably in accordance with the morphology of B. huanghuanses, I propose herein a new generic name, Songiella, for cysts originally described as B. huanghuaensis.