PYLONIOIDEA Haeckel, 1882 sensu Dumitrica, 1989

Zhang, Lanlan & Suzuki, Noritoshi, 2017, Taxonomy and species diversity of Holocene pylonioid radiolarians from surface sediments of the northeastern Indian Ocean, Palaeontologia Electronica (Cambridge, England: 2003) 7 (8), pp. 1-68 : 8-9

Superfamily PYLONIOIDEA Haeckel, 1882 sensu Dumitrica, 1989

Remarks. The taxonomic framework of the superfamily Pylonioidea was well documented by De Wever et al. (2001, p. 148-158). Our re-examination of the internal structures of members of this superfamily has largely confirmed their descriptions.

Subsuperfamily PYLONIILAE Haeckel, 1882

Family PYLONIIDAE Haeckel, 1882

Subfamily PYLONIINAE Haeckel, 1882 sensu emend. De Wever et al., 2001

Genus TETRAPYLE Müller, 1859 sensu emend. herein

*1859 Tetrapyle Müller , p. 33.

1861b Schizomma Ehrenberg , p. 822-833 (type species: Schizomma quadrilobum Ehrenberg, 1862 ).

1882 Octopyle Haeckel , p. 464 (type species: Octopyle [ Octopylissa ] ovulina Haeckel, 1887).

1887 Tetrapyle Müller ; Haeckel, p. 644.

1887 Octopyle Haeckel ; Haeckel, p. 650.

1887 Octopylura Haeckel , p. 651 (type species: Octopyle [Octypylura] stenozona Haeckel, 1887 ).

1954 Tetrapyle Müller ; Campbell, p. D96.

1954 Octopyle Haeckel ; Campbell, p. D96.

1954 Octopylura Haeckel ; Campbell, p. D96.

1979 Octopylura Haeckel ; Kozur and Mostler, p. 40.

1979 Octopyle Haeckel ; Kozur and Mostler, p. 46. Type species. Tetrapyle octacantha Müller, 1859 (monotypy).

Description. Test comprises a central combination and the repeating symmetry of four girdles. The central combination consists of a spherical S1a (microsphere) and an S1a-girdle. The S2a-girdle (G1 girdle) and S2b-girdle (G2 girdle) are joined at the Ug-axis. The G2 girdle and S2c-girdle (G3 girdle) are joined at the Fr-axis. The G3 girdle and S3a-girdle (G4 girdle) are joined at the Pr-axis. The G4 girdle is parallel to the G1 girdle. Girdles are latticed, and elliptical to rounded quadrangular in Fr-view. The shapes of the girdles are homologous. A polar beam may be present along the Lt-axis from one or both sides of the central combination. A polar beam appears to extrude from each girdle.

Remarks. Ogane and Suzuki (2009) simulated the “ever-changing appearance” of pyloniid specimens with a three-dimensional computer model and warned that an “artificial” torsional state appears at any orientation except for the Fr-, Ug- and Pr-views. In this study, the Fr-, Ug- and Pr-views correspond to the “dorsal,” “apical,” and “lateral” views. The overlapping wings and the both sides of girdles create a false illusion of deep focal depths under a microscope. Octopyle was distinguished from Tetrapyle based on that the former has polar beams that connect with two girdles. In practice, however, this criterion is problematic because of ontogenetic change from Tetrapyle - type to Octopyle - type morphology with the development of polar beams. Therefore, we synonymize Octopyle with Tetrapyle in this study.