Larcopyle cervicornis ( Haeckel, 1887 )

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 : 28-29

Larcopyle cervicornis ( Haeckel, 1887) sensu stricto

Figures 16 , 17.1-6

1887 Tholospira (Tholospironium) cervicornis Haeckel , p. 700, pl. 49, fig. 5.

1912 Tholospira cervicornis Haeckel ; Popofsky, p. 152, text-fig. 73.

1981 Tholospira cervicornis Haeckel ; Takahashi and Honjo, p. 150, pl. 5, figs. 16-17 (only).

non 1981 Tholospira cervicornis Haeckel ; Takahashi and Honjo, p. 150, pl. 5, fig. 18.

non 1984b Larcopyle sp. aff. L. bütschlii Dreyer (wrong spelling of the species name according to ICZN Article 32.5.2.1); Nishimura and Yamauchi, p. 41, pl. 16, fig. 10.

non 1984b Tholospira cervicornis Haeckel ; Nishimura and Yamauchi, p. 41, pl. 17, fig. 10.

non 1985 Tholospira cervicornis Haeckel ; Boltovskoy and Jankilevich, pl. 3, fig. 20.

non 1987 Tholospira cervicornis Haeckel ; Dworetzky and Morley, pl. 2, fig. 3.

non 1991 Tholospira cervicornis Haeckel ; Takahashi, p. 91, pl. 22, figs. 7-9, 12.

1995 Tholospironium cervicorne Haeckel ; van de Paverd, p. 185-186, pl. 54, figs. 1-4, 6-10, pl. 58, fig. 7 (not), pl. 59, fig. 6.

non 2009 Tholospira cervicornis Haeckel ; Itaki, p. 48,

pl. 11, figs. 14-18. 2009 Tholospira cervicornis Haeckel ; Matsuoka,

fig. 3.18. 2009 Larcopyle buetschlii Dreyer ; Zhang, Chen,

Xiang, Zhang, Liu, Huang, and Lu, pl. 1, fig.

L. non 2012 Tholospira cervicornis Haeckel ; Ikenoue,

Takahashi, and Tanaka, pl. 2, fig. 16. non 2014a Larcopyle cervicorne (Haeckel) ; Matsuzaki,

Nishi, Hayashi, Suzuki, Ikehara, Gyawali,

Tanaka, and Takashima, fig. 2.10. non 2015a Larcopyle cervicorne (Haeckel) ; Matsuzaki,

Suzuki, and Nishi, p. 33-34, fig. 6.15-16. non 2014c Larcopyle cervicorne Haeckel (no parenthe-

sis to the author’s name); Matsuzaki, Nishi,

Suzuki, Kawate, Takashima, and Sakai, pl.

1, fig. 19. non 2014d Larcopyle cervicorne Haeckel (no parenthe-

sis to the author’s name); Matsuzaki, Nishi,

Suzuki, Takashima, Kawate, and Sakai, pl.

2, fig. 8. non 2015b Larcopyle cervicornis Haeckel (no paren-

thesis to the author’s name); Matsuzaki,

Suzuki, Nishi, Hayashi, Gyawali,

Takashima, and Ikehara, fig. 7.7. Description. Test is spiny and elongated with very coarse pores and consists of a relatively large pylodiscid-type central combination and one or two very coarse pseudo-concentric shells or spiny surroundings. The Lt-axis in Type 1 coordinates is parallel to the longest axis of the test. The ratio of the longest axis (Lt-axis in Type 1 coordinates and Ug-axis in Type 2 coordinates) to the shortest axis of the 1st pseudo-concentric shell is ca. 1.5–1.7. Outer part of the 1st pseudo-concentric shell is surrounded with irregularly spiraled girdles, which form the 2nd pseudo-concentric shells to an extent. Pores of the 2nd pseudo-concentric shell are polygonal in shape, and the triple junction of the pore frame is always connected with the inner part of the test by a pillar beam. The 2nd pseudo-concentric shell develops from both ends of the longest direction (Lt-axis) of the test to revolve around the short axis-side of the test. The 2nd pseudo-concentric shell consists of with two girdles that encircle the longest axis of the test and two other girdles along the shortest axis of the test. Spinelike spinules tend to extend from both sides along the longest axis of the test from the 2nd pseudo-concentric shell. Pores of the 2nd pseudo-concentric shell and outer test are as large as 15–25 μm in diameter. Remarks. The species name “ Tholospira cervicornis ” has been applied for two distinct morphotypes:

PALAEO- ELECTRONICA.ORG one shown on plate 5, figures 16 and 17 and the other on plate 15, figure 18 of Takahashi and Honjo (1981), for example. The detailed skeletal characteristics in the type image of this species by Haeckel (1887) are somewhat unclear. According to the original description of this species by Haeckel (1887, p. 700), this species has “perimeter of the lateral plane elliptical, one and a third times as long as broad. Four internal kidney-shaped gates, as in Tetrapyle . Both wings of the sagittal girdle turn round one another in one and a half to two double spiral turns.” Here, the topotypes from the H.M.S. Challenger Station 271, housed at Tohoku University, are shown in Figure 17.1-6 to more clearly represent this species. The features of these specimens are consistent with those in plate 5, figures 16 and 17 of Takahashi and Honjo (1981). The internal structures of these topotypes were similar to the specimen illustrated in text-figure 73 of Popofsky (1912). Larcopyle cervicornis ( Haeckel, 1887) is easily distinguished from other Larcopyle species based on its elongate form, the distinctive pylodiscid central part that is parallel to the shortest axis, the twin G2-gates aligned along the longest axis of the test, and its very coarse pores. This species has multi-branched (fork-shaped) spines according to original description and drawing by Haeckel (1887), and such characteristic has been shown in Takahashi and Honjo (1981, plate 5, figure 17) and Itaki (2009, plate 11, figures 14, 18). However, it isn’t always clear in microphotographs showing in Figure 16 .

Figures

FIGURE 16. Photographs of the encountered morphotypes of Larcopyle cervicornis (Haeckel, 1887) sensu stricto. All are Pl-view at Type 1. Scale bar equals 0.1 mm. All specimens are from YDY05-01.

FIGURE 17. The topotypes from the H.M.S. Challenger station 271. 1-6, Larcopyle cervicornis (Haeckel, 1887); 7-12, Larcopyle buetschlii buetschlii Dreyer, 1889. All are Pl-view at Type1. Scale bar equals 0.1 mm. All specimens are from H.M.S. Challenger Station 271 sample.