HALIOMMIDAE Ehrenberg, 1846

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 : 438-439

Family HALIOMMIDAE Ehrenberg, 1846

sensu Suzuki emend. herein

Haliommatina Ehrenberg, 1846: 385 [as a family]; 1847: 54 [as a family]; Ehrenberg 1876: 156. — Schomburgk 1847: 124, 126 [as a family].

Haliommatida – Haeckel 1862: 239, 412, 423 [as a tribe]. — Mivart 1878: 177 [as a subdivision of the subsection Ommatida].

Carposphaerida Haeckel, 1882: 451 [nomen dubium, as a tribe]; 1887: 60, 85 [as a subfamily]. — Schröder 1909: 5 [as a subfamily].

Cromyosphaerida Haeckel, 1882: 453 [as a tribe]; 1887: 60, 84 [as a subfamily]. — Schröder 1909: 5 [as a subfamily].

Haliommida – Haeckel 1887: 208, 230 [as a subfamily]. — Schröder 1909: 16 [as a subfamily].

Carposphaerinae – Clark & Campbell 1942: 20 [nomen dubium]; 1945: 9. — Chediya 1959: 70.

Cromyosphaerinae – Campbell & Clark 1944a: 9. — Campbell 1954: D50. — Chediya 1959: 72.

Haliomminae – Campbell & Clark 1944a: 16; 1944b: 11. — Clark & Campbell 1945: 17. — Chediya 1959: 97.

Cenosphaeridae Deflandre, 1953: 420-421. — Hollande & Enjumet 1960: 68, 86. — Petrushevskaya 1975: 567. — Dumitrica 1979: 18. — Anderson 1983: 49.

Haliommidae – Petrushevskaya 1975: 568; 1979: 105-106. — Dumitrica 1979: 20.

TYPE GENUS. — Haliomma Ehrenberg, 1839: 128 [invalid subsequent designation (new subsequent designation in this revision): Haliomma medusa Ehrenberg, 1839: 130 ].

INCLUDED GENERA. — Cromyosphaera Haeckel, 1882: 453 (= Cromyommetta n. syn.; Cromyommura synonymized by Matsuzaki et al. 2015:7). — Haliomma Ehrenberg, 1839: 128 (= Actinommilla n. syn., Cenosphaera n. syn., Circosphaera n. syn.; Thecosphaerella synonymized by Petrushevskaya 1975: 568). — Haliommantha Haeckel, 1887: 230 . — Hexacontella Haeckel, 1887: 194 . — Melittosphaera Haeckel, 1882: 451 (= Conoactinomma n. syn.). — Pseudostaurosphaera Krasheninnikov, 1960: 276 (= Pseudostaurolonche synonymized Kozlova 1999: 75).

INVALID NAME. — Circulosphaera.

NOMINA DUBIA. — Chaunosphaera, Prunosphaera , Thecosphaerantha , Thecosphaerina , Thecosphaeromma .

JUNIOR HOMONYM. — Porosphaera Haeckel, 1887 (= Chaunosphaera) nec Steinman, 1878.

DIAGNOSIS. — Two to three, rarely more than three, concentric spherical shells with many non-bladed radial beams. Central structure consists of a double medullary shell. Both shells of the double medullary shell are latticed, spherical in shape, and connected by many radial beams. Radial spines may be present or absent. Nodelike or by-spine-like short spines are observable in some species.

Endoplasm is illustrated in the Cromyommetta -form of Cromyosphaera and in Haliomma . Endoplasm is gray to light gray in color and fills the double medullary shell. It is also distributed around the medullary shell in younger forms and occupies a large portion of the cortical shell. The axopodial system is unknown. No algal symbionts were observed.

STRATIGRAPHIC OCCURRENCE. — Late Paleocene-Living.

REMARKS

Differing from the Actinommidae , the Haliommidae are distinguished by the presence of non-bladed radial beams. This family may include a single-latticed, cortical shell member whose internal shells and radial beams have been lost or dissolved. Pseudostaurosphaera is tentatively included in this family as the similarity to the number of shells of Melittosphaera was taken into consideration. The taxonomic differences between Haliomma , Haliommantha and Melittosphaera require further study.

The catalogue finally synonymized Cenosphaera with Haliomma following anatomical observations and rules included in the Code. The type species of Cenosphaera ( Cenosphaera plutonis ) was illustrated without any information about its internal structure ( Ehrenberg 1854c: pl. 35B-B.IV, fig. 20). The genus was originally defined as a single shell genus ( Ehrenberg 1854b: 237). However, the real type-specimen illustrated and archived in the Ehrenberg collection possessed three concentric shells ( Suzuki et al. 2009c: pl. 30, figs 1a-1d). Under the principles of the Code, “ every name within the scope of the Code [...] is permanently attached to a name-bearing type.” (see the Principles in the Introduction). Conforming to this rule, Cenosphaera based on the name-bearing type is a genus with three concentric shells, thus Haliomma is the oldest senior synonym for the group of Cenosphaera under this sense. This solution avoids an important instability and confusion between one-shelled and three-shelled genera. Conversely, we expanded the definition of Ethmosphaera to include the previous oneshelled species in order to avoid further potential confusion. Here, Hexacontella is included into Haliommidae due to the presence of non-bladed radial beams directly connected with bladed six radial spines (Dumitrica’s personal observation).

Haliomma poses certain problems to common morphology if referring to the type material for Haliomma medusa Ehrenberg, 1839 (type species of Haliomma in the Ehrenberg collection). The illustration (publishes in pl. 22, figs 34a, 34b of Ehrenberg 1854c) appears to show six radial beams inside the shell. This drawing corresponds to the type specimen found and examined in the Ehrenberg collection ( Suzuki et al. 2009c: pl. 1, fig. 3d). However, this type material contains several specimens of the morphotype that look identical, if the differing number of radial beams are not considered ( Suzuki et al. 2009c: pls 1-3). This suggests intraspecific variability of H. medusa based on the number of radial beams. In light of this infra-species variation, the definition of Haliomma is expanded in so far as to include the morphotypes with variable numbers of radial beams. These morphotypes are generally identified as Thecosphaera (with non-bladed radial beams in the original diagnosis), but the representative genus can no longer be used because the type species is a Mesozoic nomen dubium ( Thecosphaera unica Rüst, 1885 ). Although there is some doubt regarding the shape of the radial beams in the lectotype of H. medusa , the presence of non-bladed radial beams is considered specific to Haliomma .

Internal skeletal structure was illustrated for Cromyosphaera ( Nishimura 1992: pl. 1, fig. 11), Haliomma (Sugiyama et al. 1992: pl. 1, fig. 4; pl. 4, figs 1, 4; Suzuki 1998b : pl. 3, figs 4, 5; pl. 6, figs 3, 4) and Melittosphaera (Barwicz-Piskorz 1997: pl. 1, fig. 1;1999: figs 2.B-2.G). Protoplasm and algal symbionts were documented with epi-fluorescent observation with DAPI dyeing in the Cromyommetta -form of Cromyosphaera ( Zhang et al. 2018: 17, fig. 4) and Haliomma ( Zhang et al. 2018: 17, figs 7, 8). Some undescribed genera probably belonging to the Haliommidae remain ( Hollis 1997: pl. 3, fig. 6: Jackett & Baumgartner 2007: pl. 1, fig. 37; Jackett et al. 2008: pl. 3, fig. 1).

VALIDITY OF GENERA

Cromyosphaera

Cromyommetta is characterized by regular pores with same sizes on the cortical shell, four concentric lattice shells, and numerous radial spines ( Campbell 1954: D66). The type species of Cromyomma was subsequently designated as Cromyomma villosum in the Atlas due to an invalid designation of the type species by Campbell (1954). The “numerous radial spines” in the definition correspond to spiny by-spines in the modern terminological sense. The occurrence of by-spines is not used as a genus criterion in the Haliommoidea . The oldest available name is Cromyosphaera among them.

Haliomma

The same type species is designated for Cenosphaera and Circosphaera. As explained in the remarks for the Ethmosphaeridae and Haliommidae , the lectotype of Cenosphaera has three concentric shells with many radial beams, differing from the widely applied concept of a single cortical shell with an empty space. This structure is exactly the same as the current concept of Thecosphaera and Haliomma in the Atlas . Actinommilla was newly established as a subgenus of Actinomma by Haeckel (1887: 254) and is marked by irregular pores with dissimilar sizes on the cortical shell and spines covering the entire surface of the cortical shell ( Campbell 1954: D65-66). The “spines” is an interpretation of by-spines if the illustration of the type species of Actinommilla is referred. Differences in both pores and by-spines on the cortical shell are variable within or between species. Haliomma is the oldest available genus among them.

Melittosphaera

Melittosphaera is characterized by one medullary shell, one cortical shell whose pores within hexagonal frames are circular or hexagonal in shape and dissimilar in size, radial beams joining two shells, and no radial spines on the shell surface ( Campbell 1954 as Melitosphaera [sic]: D48). Conoactinomma is defined by three concentric shells, conical protuberances (“tubercles”) on the cortical shell, and by-spines on each tubercle (Gorbunov in Kozlova & Gorbovetz 1966: 104). The supporting image of Conoactinomma in the Atlas shows a “weak” shadow of the innermost double medullary shell but this type of shell is easily dissolved. In consideration of difference on the resistance on preservation effect, Conoactinomma is separated from Haliomma . As Melittosphaera looks to lose the innermost double medullary shell, this genus is also separated from Haliomma until an exact observation could be carried out for both these genera. Roughness of the cortical shell is different between Melittosphaera and Conoactinomma but this difference is not so significant. It is unnecessary to differentiate them at the genus level. Melittosphaera is an available name older than Conoactinomma.