COLLOSPHAERIDAE Müller, 1859

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 : 528-530

Family COLLOSPHAERIDAE Müller, 1859

Collosphaeren Müller, 1859a: 17 [as a family].

Collosphaerida – Haeckel 1862: 240, 530-531 [as both family and tribe]; 1882: 471 [as a family]; 1884: 29 [as a family];1887: 55, 92- 94 [as a family]. — Mivart 1878: 179 [as a subsection]. — Brandt 1885: 252-254. — Bütschli 1889: 1949 [as a family]. — nec Rüst 1892: 140 [as a family]. — Afanasieva & Amon 2006: 157 [as a class].

Collosphaeridae – Claus 1876: 160. — Delage & Hérouard 1896: 203 [as a suborder]. — Enriques 1919: 57; 1932: 983. — Campbell 1954: D51. — Chediya 1959: 74. — Riedel 1967b: 294; 1971: 650. — Riedel & Sanfilippo 1971: 1586; 1977: 862. — Strelkov & Reshetnyak 1971: 329-332. — Dumitrica 1973a: 831. — Sanfilippo & Riedel 1973: 485. — Nakaseko et al. 1975: 166. — Nakaseko & Sugano 1976: 119. — Tan & Tchang 1976: 226. — Reshetnyak & Runeva 1978: 6-7. — Dumitrica 1979: 26-27. — Tan & Su 1982: 137. — Anderson 1983: 37, 71. — Cachon & Cachon 1985: 285. — Sanfilippo et al. 1985: 650. — Petrushevskaya 1986: 123. — Takahashi 1991: 53. — van de Paverd 1995: 35-37. — Chen & Tan 1996: 150. — Boltovskoy 1998: 30-31. — Tan 1998: 104. — Anderson et al. 2002: 1001. — De Wever et al. 2001: 169, 171. — Afanasieva et al. 2005: S306. — Chen et al. 2017: 93.

Acrosphaerida Haeckel, 1882: 471 [as a subfamily]; 1887: 94 [as a subfamily].

Clathrosphaerida Haeckel, 1882: 472 [as a subfamily]; 1887: 94, 118 [as a subfamily].

Collosphaeriden – Brandt 1905: 327-328 [as a family]. — Lankester et al. 1909: 145 [as a family]. — Popofsky 1917: 239 [as a family].

Collosphaerinae – Campbell 1954: D51.

Clathrosphaerinae – Campbell 1954: D52. — Chediya 1959: 77.

Acrosphaerinae – Chediya 1959: 74.

Collosphaerini – Strelkov & Reshetnyak 1971: 332.

Acrosphaerini – Strelkov & Reshetnyak 1971: 338-339

Siphonosphaerini Strelkov & Reshetnyak, 1971: 348.

TYPE GENUS. — Collosphaera Müller, 1855: 238 [type species by subsequent designation ( Campbell 1954: D51): Thalassicolla (Collosphaera) huxleyi Müller, 1855: 238 ].

INCLUDED GENERA. — Choenicosphaera Haeckel, 1887: 102 (= Choenicosphaerula with the same type species; Choenicosphaerium n. syn., Coronosphaera n. syn., Trypanosphaerium n. syn.; Trypanosphaera , Trypanosphaerula synonymized by Menshutkin & Petrushevskaya 1989: 91). — Clathrosphaera Haeckel, 1882: 472 (= Clathrosphaerula with the same type species). — Collosphaera Müller, 1855: 238 (= Dyscollosphaera with the same type species; Collodiscus n. syn., Conosphaera n. syn., Myxosphaera n. syn.). — Disolenia Ehrenberg, 1861b: 831 (= Solenosphaera, Tetrasolenia synonymized by Haeckel 1887: 113, Trisolenia synonymized by Haeckel 1887: 114). — Otosphaera Haeckel, 1887: 116 . — Polysolenia Ehrenberg, 1861b: 832 (= Acrosphaera synonymized by Nigrini 1967: 14; Clathrosphaerium synonymized by Matsuzaki et al. 2015: 4, Mazosphaera synonymized by Menshutkin & Petrushevskaya 1989: 93, Odontosphaera n. syn.). — Siphonosphaera Müller, 1859b: 59 (= Holosiphonia with the same type species; Merosiphonia synonymized by Riedel 1971: 651; Solenosphactra synonymized by Menshutkin & Petrushevskaya 1989: 95; Solenosphenia n. syn., Solenosphyra n. syn.). — Tribonosphaera Haeckel, 1882: 471 (= Buccinosphaera , Pharyngosphaera synonymized by Menshutkin & Petrushevskaya 1989: 90).

NOMEN NUDUM. — Pentasolenia

NOMINA DUBIA. — Caminosphaera , Eucollosphaera , Xanthiosphaera .

JUNIOR HOMONYM. — Pachysphaera Brandt, 1902 nec Pilsbry in Tryon & Pilsbry, 1892.

DIAGNOSIS. — Collosphaeridae consist of colonial Collodaria with tens, hundreds or more collodarian cells, depending on the size of the colony. Each collodarian cell has one or two, rarely more, spherical cortical shells. The intracapsular zone is always located inside the cortical shell. Each cell has multi-nuclei, at least in Collosphaera and Disolenia . Algal symbionts are observed within the cortical shell or outside of it, but little is known about their specific location at genus- or species- levels.

STRATIGRAPHIC OCCURRENCE. — early Early Miocene-Living.

REMARKS

In sediments, the Collosphaeridae are identifiable at species level. Unfortunately, the Collosphaeridae are usually poorly preserved in sediments. A single colony contains variable morphotypes of one probable species. The morphological variations at the species level and taxonomic scheme at the genus level were repeatedly studied ( Knoll & Johnson 1975; Menshutkin & Petrushevskaya 1989; Petrushevskaya & Swanberg 1990). However, their contributions are difficult to apply for further studies. The first occurrences of Collosphaera tuberosa and Tribonosphaera invaginata are important in determining the RN16 (0.51±0.08 Ma at the base) and RN17 (0.34±0.11 Ma at the base) radiolarian biozones in the tropical region ( Sanfilippo & Nigrini 1998). The first occurrence of Siphonosphaera abyssi is also key to determining the boundary of 1.80 Ma in the Northwest Pacific ( Matsuzaki et al. 2014). Thus, the identification of these three species is critical. The critical identification was explained in detail in Matsuzaki et al. (2015: 5) for S. abyssi and the morphological changes of Tribonosphaera (originally Buccinosphaera ) were stratigraphically recognized inKnoll & Johnson (1975). The determinable morphological character for Tribonosphaera is best illustrated in van de Paverd (1995: pl. 4, figs 2a, 4). Differing from other Collodaria families, the Collosphaeridae are the only family which provide a connection between our knowledge of living and fossil forms. In the fossil record, the evolution of Polysolenia (= Acrosphaera in original), Collosphaera and Disolenia (= Trisolenia ) were recorded since the early Miocene (c. 20 Ma) ( BjØrklund & Goll 1979). Collosphaera was used for biological research on ultrafine cellular structures ( Anderson 1978a; 1983), assimilation of organic substances from algal symbionts using 14 C ( Anderson 1978a; Anderson et al. 1983; 1985), binary fission on live (Anderson & Swanberg 1981; Anderson & Gupta 1998), and silicalemma containing granular masses forming the siliceous skeleton (Anderson 1981: figs 13.14-13.17). Moreover, the silicalemma function of Polycystinea was based on the study of Collosphaera . Collosphaeridae are relatively easy to identify at the genus level. Consequently, images of living specimens were published in many papers. “Living” images were illustrated for Collosphaera ( Anderson 1978a: fig. 1; 1980: fig. 8; 1983: figs 1.5.E-1.5.F; Anderson & Gupta 1998: figs 1-7; Suzuki & Aita 2011: figs 5H, 5I; Probert et al. 2014: S1, PAC 2, 7; Suzuki & Not 2015: fig. 8.13.8, 8.13.9; Matsuoka et al. 2017: appendix A), Otosphaera ( Suzuki & Not 2015: fig. 8.13.12), Polysolenia ( Caron & Swanberg 1990: fig. 3.C), Siphonosphaera ( Casey 1993: fig. 13.6: Suzuki & Not 2015: fig. 8.13.11), Disolenia (Anderson 1983: fig. 1.4.A; Caron & Swanberg 1990: fig. 3.A; Matsuoka 2007: fig. 5.b; Suzuki & Not 2015: fig.8.13.13-8.13.15), and Tribonosphaera ( Suzuki & Not 2015: fig. 8.13.10). The skeletal structure, including the growth line, was documented for Polysolenia ( Nishimura 1986: figs 6.1-6.2), Disolenia ( Nishimura 1986: fig. 6.3), Tribonosphaera ( van de Paverd 1995: pl. 4, figs 2a, 4). These results are not applicable as a general rule for all Polycystinea due to the differences in skeletal formation of Nassellaria and Spumellaria . Though a powerful detection tool to define on-time silicification phenomena, PDMPO and HCK-123 failed to catch silicification phenomena for any collodarian specimens (not reported inOgane et al. 2009c, 2010 because of negative results). Any results based on Collosphaeridae should not be overgeneralized in Polycystinea. From a historical point of view, the study of symbionts in Collosphaeridae is of particular interest. The algal symbionts and the nucleus of host were documented using DAPI dyeing epi-fluorescent observation for Collosphaera ( Suzuki et al. 2009b: figs 1I-1K; Zhang et al. 2018: 11, fig. 4, p. 13, figs 1-4), Mazosphaera ( Zhang et al. 2018: 13, figs 6-8), Disolenia ( Suzuki et al. 2009b: figs 1L, 1M; Zhang et al. 2018: 11, figs 9, 10, p. 13, fig. 5), Polysolenia ( Zhang et al. 2018: 11, fig. 21; p. 13, figs 9, 12, 13), Otosphaera ( Zhang et al. 2018: 11, fig. 22; p. 13, figs 10, 11), Polysolenia ( Zhang et al. 2018: 11, fig. 25), Siphonosphaera ( Zhang et al. 2018: 13, figs 14-17). The algal symbionts of Collosphaera were identified as Brandtodinium nutricula by Probert et al. (2014). Merodinium mendax parasites in Collosphaera were reported by Chatton (1923) but integrative morpho- and molecular studies have not been conducted as of yet.

VALIDITY OF GENERA

Choenicosphaera

The combinations Choenicosphaera and Choenicosphaerula , and Trypanosphaera and Trypanosphaerula have the same type species. The genera listed here are subdivided into a group with poreless, hyaline shells ( Choenicosphaera and Trypanosphaera ) and a group with shells with pit-like pores ( Choenicosphaera , Coronosphaera , and Trypanosphaerium ). Choenicosphaera is defined by coronal radial spines around a large pore and a crown of spines around each pore ( Campbell 1954: D52). These characteristics fit the type-illustration of Coronosphaera diadema , the type species of Coronosphaera ( Haeckel 1887: pl. 7, fig. 3). Coronosphaera is characterized by pores prolonged outward in fenestrate tubules ( Campbell 1954: D52). This difference is insufficient to separate them into two genera. According to Campbell (1954: D52), Trypanosphaerium is similar to Coronosphaera , but differs from the latter by solid walled tubules. This and the type-illustration of Trypanosphaera coronata ( Haeckel 1887: pl. 5, fig. 3), the type species of Trypanosphaerium , fit the definition of Choenicosphaerium . Trypanosphaera has solid walled tubules and its pores all have tubules ( Campbell 1954: D52). This explanation and the type-illustration of Trypanosphaera trepanata , the type species of Trypanosphaera , fit the characteristics of Choenicosphaera . Although it is unclear whether the genera with hyaline shells can be synonymized with the genera with pit-like pores on the shells, we tentatively synonymize all genera listed here. All of these genera were published simultaneously in Haeckel (1887: D102 for Choenicosphaera ; D103 for Choenicosphaerium ; D109 for Trypanosphaera ; D110 for Trypanosphaerium ; and D117 for Coronosphaera ). There were no differences in taxonomic stability, thus the first genus was selected as the valid genus.

Collosphaera

The combinations Collosphaera and Dyscollosphaera , and Myxosphaera and Collodiscus each have the same type species. Müller (1855 a: 238) described Collosphaera as “ a light-yellow cell surrounded by a fragile transparent spherical shell perforated by numerous circular pores ” (summary from the translation of Müller 1855 a). Brandt (1885: 254) erected Myxosphaera for Sphaerozoum coeruleum , whose reproductive process differs from other Collosphaeridae and Sphaerozoidae .This original definition is useless for specifying any collodarian genera because no collodarian reproductive processes have been examined with modern techniques. Brandt (1885) noted other characteristics of Myxosphaera : “ the thickness of the central capsule wall; the appearance of blue pigmentation during swarmer formation; and no siliceous skeleton ” (translated from Brandt 1885). Collosphaera has a naked mode like Myxosphaera ; consequently, they can be synonymized. Collosphaera tuberosa and Buccinosphaera invaginata seemed to have evolved from Collosphaera orthoconus , referring to BjØrklund & Goll (1979). C. orthoconus resembles Conosphaera platyconus , the type species of Conosphaera ( Haeckel 1887: pl. 12, fig. 3); consequently, Conosphaera is a synonym of Collosphaera . The oldest name is Collosphaera .

Disolenia

The synonymized opinion on the four genera Disolenia , Solenosphaera, Tetrasolenia , and Trisolenia was already accepted in the 1880s ( Haeckel 1887: 113; Strelkov & Reshetnyak 1971: 358; BjØrklund & Goll 1979: 1317-1318). However, the valid genus name is disputed and there are two problems. One is the type species for these four genera. Solenosphaera has the same type species as Tetrasolenia ( Tetrasolenia quadrata ). The type species of Trisolenia is Trisolenia megalactis , by subsequent monotypy. Matsuzaki et al. (2015: 6) subsequently designated Trisolenia zanguebarica as the type species of Disolenia , after radiolarians examined by Ehrenberg himself were found in the Ehrenberg collection. Thus, all of these genera are available taxonomic names . The second problem is which genus is the oldest; Solenosphaera used to be a valid genus, but this is obviously illegal because this genus was established in 1887 to “kill” Ehrenberg’s Disolenia, Tetrasolenia , and Trisolenia ( Haeckel 1887: 113) . Ehrenberg’s genera were published simultaneously in Ehrenberg (1861b: 831 for Disolenia and 833 for Tetrasolenia and Trisolenia ). Campbell (1954: D52) and Nigrini (1967: 19) both validated Disolenia over Tetrasolenia and Trisolenia . As the first reviser’s decision was retained under ICZN (1999), Disolenia was already a legal valid name.

Polysolenia

As noted in the remarks in the Atlas , the type species of Acrosphaera is not Polysolenia setosa , which was subsequently designated by Campbell (1954: D52). The correct type species is Collosphaera spinosa , a subsequent monotypy by Brandt (1885: 263). The controversy over whether Acrosphaera or Polysolenia is the valid name has existed since 1954 (see the historical review in Matsuzaki et al. 2015: 4), but this discussion was wasted because it started from the objective synonymy between Acrosphaera and Polysolenia . This is wrong logically, but the result is the same because Collosphaera spinosa was classified in Polysolenia ( Matsuzaki et al. 2015: 4-5) . Mazosphaera is obviously the same as Polysolenia . Clathrosphaerium differs from Polysolenia by the presence of a web-like mesh around the Polysolenia -form shell, which differs at intra- and infraspecific levels. Odontosphaera was tentatively synonymized with Polysolenia by the presence of a hooked spine on its pores, like Collosphaera spinosa . Acrosphaera was published in 1882. Mazosphaera and Polysolenia , the oldest available names , were published simultaneously inEhrenberg (1861b: 832 for both genera). Since several papers use Polysolenia , this genus is validated here.

Siphonosphaera

BjØrklund & Goll (1979) considered Siphonosphaera a junior synonym of Disolenia ( Solenosphaera originally). As the typical Siphonosphaera in a colony has a uniform morphotype, differing from the high variation in the number of tubules and shell shapes in Disolenia ( Haeckel 1887: 113) , we keep Siphonosphaera as an independent genus. Holosiphonia has the same type species as Siphonosphaera . Merosiphonia and Solenosphactra have already been synonymized (Riedel 1971: 651; Menshutkin & Petrushevskaya 1989: 95). Solenosphyra is marked by funnel-shaped, outwardly flaring tubules ( Campbell 1954: D52). The most similar real specimen is shown in the support image for Solenosphyra in the Atlas . This specimen is very similar to Siphonosphaera and it is not necessary to separate it as an independent genus. An actual specimen identifiable as Solenosphaera ascensionis , the type species of Solenosphenia , has not been reported. This genus looks similar to Disolenia , but is tentatively synonymized with Solenosphaera considering the well-developed tubules and spherical cortical shell. The oldest available name is Siphonosphaera .