THALASSOSPHAERIDAE Haeckel, 1862

Suzuki, Noritoshi, Caulet, Jean-Pierre & Dumitrica, Paulian, 2021, A new integrated morpho- and molecular systematic classification of Cenozoic radiolarians (Class Polycystinea) - suprageneric taxonomy and logical nomenclatorial acts, Geodiversitas 43 (15), pp. 405-573 : 533-534

Family THALASSOSPHAERIDAE Haeckel, 1862

Thalassosphaerida Haeckel, 1862: 237, 246, 255 [as both family and tribe];1882: 470 [as a family]; 1884: 28 [as a family]; 1887: 10, 29-30 [as a family]. — Bütschli 1889: 1947 [as a family]. — Ludwig 1908: 17 [rank unknown]. — Anderson 1983: 23. — Afanasieva & Amon 2006: 157 [as a class].

Thalassosphaeridae – Claus 1876: 158. — Delage & Hérouard 1896: 178 [as a suborder]. — Campbell 1954: D45. — Chediya 1959: 66. — De Wever et al. 2001: 171. — Afanasieva et al. 2005: S306. — Chen et al. 2017: 81.

Physematidae Brandt, 1902: 81-82 [nomen dubium]. — Hollande & Enjumet 1953: 107, 112, 129. — Cachon & Cachon 1985: 284.

Physematiidae – Lankester et al. 1909: 144 [nomen dubium].

Physematiden – Huth 1913: 25 [nomen dubium, as a family].

Bathysphaeridae Hollande & Enjumet, 1960: 127 [junior homonym]. — Cachon & Cachon 1985: 285.

TYPE GENUS. — Thalassosphaera Haeckel, 1862: 259 [type species by subsequent designation ( Campbell 1951: 527): Sphaerozoum bifurcum Haeckel, 1861b: 845 ]

INCLUDED GENERA. — Lampoxanthura Haeckel, 1887: 38 . — Thalassosphaera Haeckel, 1862: 259 (nec Haeckel, 1887) (= Thalassoxanthomma with the same type species). — Thalassoxanthella Haeckel, 1887: 31 .

NOMINA DUBIA. — Calosphaera , Lampoxanthella , Lampoxanthium , Lampoxanthomma , Physematium, Thalassiosolen , Thalassorhaphis , Thalassoxanthium .

JUNIOR HOMONYMS. — Thalassoplancta Haeckel, 1887 (= Thalassorhaphis ) nec Haeckel, 1882; Thalassosphaera Haeckel, 1887 (= Calosphaera ) nec Haeckel, 1862.

DIAGNOSIS. — Thalassosphaeridae consist of solitary Collodaria . The protoplasm consists of a single central large nucleus surrounded by an endoplasm. A very high number of isolated siliceous spicules are scattered outside the endoplasm.

STRATIGRAPHIC OCCURRENCE. — Living.

REMARKS

No molecular data was obtained but the Thalassosphaeridae are suspected to be one of the different living stages of Thalassicollidae (see remarks for Thalassicollidae ). This family includes the first described polycystine genus in history, namely Physematium , but the original images in Meyen (1834) are too ambiguous, making it difficult to determine real specimens without a dose of interpretative imagination. However, the ecology of Physematium has been studied in wide area of open oceans. In this sense, there are several studies on the functional morphology of the colony ( Anderson et al. 1986b), the trophic activity (Swanberg & Anderson 1985; Swanberg et al. 1986a), as well as their feeding preferences ( Swanberg et al. 1986b). “Living” images were illustrated for Lampoxanthura (Anderson 1983: figs 1.2.C-1.2.D), Thalassosphaera ( Suzuki & Aita 2011: fig. 5E; Suzuki & Not 2015: fig. 8.13.2), “ Physematium ” (Anderson 1983: figs.1.2.A-1.2.B; Anderson et al. 1986b: figs 1.1-1.2) and “ Thalassoxanthium ” ( Hollande & Enjumet 1953: fig. 18). However, these “living images” were obtained for nomina dubia genera such as “ Physematium ” and “ Thalassoxanthium ”. Many undescribed “genera” of Thalassicollidae are also commonly found in plankton samples.