Larcopyle buetschlii chenmuhongi, Zhang, Lanlan & Suzuki, Noritoshi, 2017

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 : 34

Larcopyle buetschlii chenmuhongi n. subsp.

Figure 20

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1977 Larcopyle butschlii Dreyer (wrong spelling of the species name); Kling, pl. 1, fig. 11.

1978 Litheliidae gen. et spp. indet. Riedel and Sanfilippo, pl. 3, figs. 17?, 20.

1981 Larcopyle butschlii Dreyer (wrong spelling of the species name); Takahashi and Honjo, p. 150, pl. 5, fig. 15.

1985 Larcopyle buetschlii Dreyer ; Boltovskoy and Jankilevich, pl. 3, fig. 14.

? 1986 Pyloniid group Mullineaux and Westberg-Smith, pl. 2, fig. 2.

1991 Larcopyle butschlii Dreyer (wrong spelling of the species name); Takahashi, p. 91, pl. 22, fig. 2 (only).

2009 Larcopyle buetschlii Dreyer ; Sono, Suzuki, Yoshimura, Kano, and Takeda, pl. 1, figs. 17a-19b.

2012 Larcopyle buetschlii Dreyer ; Hernández-Almeida, BjØrklund, Sierro, Filippelli, Cacho, and Flores, pl. 2, fig. 8.

Etymology. In honor of Prof. Chen Muhong, a Chinese radiolarian specialist.

Holotype. Specimen in Figure 20.5-6 from the sample YDY05-01.

Paratype. Specimen in Figure 20.15-16 from the sample YDY05-01.

Description. Test is ellipsoid in shape with a bore pylome and consists of a pylodiscid-type central combination and one or two pseudo-concentric shells. The Lt-axis in Type 1 coordinates is parallel to the shortest axis of the test. The 1st pseudo-concentric shell has a flat, triangular form in Sg-view in Type 1 coordinates. Two large gates are visible in the 1st pseudo-concentric shell in Sg-view in Type 1 coordinates. Subsequent girdles develop along the Lt-axis from both ends of the 1st pseudo-concentric shell, and these girdles form the 2nd pseudo-concentric shell or the outermost coverage shell with subsequent girdles. The subsequent girdles are difficult to recognize as independent girdles or pseudo-concentric shells. Caps may develop at the apex and pylomate ends of the test in fully mature forms. The outermost coverage shell is fragile, and pores on the surface of the test at any ontogenetic stages are irregular in shape and size.

Remarks. This subspecies has also been included in the Larcopyle buetschlii group. This subspecies is differentiated from Larcopyle buetschlii buetschlii Dreyer, 1889 , based on the presence of two large gates in the Sg-view in Type 1 coordinates, larger pores on each girdle, and the fragile outermost coverage shell. This species is easily distinguished from Larcopyle cervicornis ( Haeckel, 1887) because the latter has a more elongated central part with two gates, more coarsely latticed girdles, a looser spiral structure, and no outermost coverage shell.

Dimensions. Based on the holotype specimen. The width of the central combination (S1a): 18.1 μm; The length of the S1a-girdle: 13.3 μm; The height of the 1st pseudo-concentric shell: 44.6 μm; The length and width of the outermost coverage shell: 100.7 μm and 65.5 μm. The length ratio to the width of the outermost coverage shell: ca. 1.5.

Figures

FIGURE 20. Photographs of the encountered morphotypes of Larcopyle buetschlii chenmuhongi n. subsp. All are Fr- view at Type 2. Scale bar equals 0.1 mm. All specimens are from YDY05-01.