Lophophaena arie, Trubovitz, Sarah, Renaudie, Johan, Lazarus, David & Noble, Paula, 2022

Trubovitz, Sarah, Renaudie, Johan, Lazarus, David & Noble, Paula, 2022, Late Neogene Lophophaenidae (Nassellaria, Radiolaria) from the eastern equatorial Pacific, Zootaxa 5160 (1), pp. 1-158 : 53

Lophophaena arie n. sp.

Plate 26, Figs. 1A – 6 (?7A–C).

urn:lsid:zoobank.org:act:D0F6C5BB-51B6-4520-BFC8-09B0B331B0CB

unknown plagonid group C sp 23, Trubovitz et al., 2020, supplementary data 7.

Diagnosis. Large Lophophaena with a cephalis that reaches its widest point near the top, and is flattened on the dorsal side where the apical spine is fused to the wall.

Description. This species is relatively large, with a high cephalis that becomes progressively wider toward the top until a point ~¾ of the way up, where it rounds smoothly toward the apex. The apical spine runs along the wall of the cephalis, and extends as a very short, thornlike spine where the cephalis reaches its maximum width. Pores on the cephalis are small, closely spaced, and regular in size and shape. They are close in size to those on the thorax, but may be slightly smaller. The neck area is long, and exhibits a bulge on the dorsal side where the AD and AL arches run along the shell wall. The ventral spine protrudes approximately perpendicular to the apical spine, and can be bladed and triangular in shape. The dorsal and lateral spines extend as thick appendages near the top of the thorax.

Remarks. This species resembles Peromelissa thoracites (Haeckel) Matsuzaki et al., 2015 (Pl. 38, Figs. 7A – 10 ) in general structure and proportions, but is significantly larger and no specimens of intermediate size were observed that would suggest an intraspecific morphological gradient. It also differs in having a short, thorn-like apical horn, rather than the straight and usually relatively longer horn present in P. thoracites . This species often stands out in assemblages for having an unusually large cephalis for a lophophaenid. A questionable specimen is included on Plate 26, Figs. 7A–C . This individual has an unusual flare on the ventral side of the cephalis, and a more pronounced gradient in pore size than the other specimens observed, but it shares the other characteristics and so is considered an atypical specimen of L. aerie rather than a different taxon. So far no specimen has been found with the thorax fully preserved, so the complete size and shape of the thorax of this species are not known.

Material examined. 17 specimens observed from samples 321-1337A-16H- 6, 121–124cm (Late Miocene), 321-1337A-12H-5, 23–26cm (Late Miocene), 321-1337A-7H- 6, 104–107cm (Early Pliocene), 321-1337A-6H-3, 29–32cm (Late Pliocene), 321-1337A-5H-5, 11–14cm (Late Pliocene), 321-1337A-4H- 6, 115–118cm (Early Pleistocene), 321-1337A-4H-2, 16–19cm (Middle Pleistocene), 321-1337A-3H- 2, 103–106cm (Middle Pleistocene), and 321-1337A-2H-3, 76–79cm (Late Pleistocene).

Holotype. Pl. 26, Fig. 1A–B ; sample 321-1337A-3H- 2, 103– 106cm ; ECO-126; H11-1.

Paratypes. (1) Pl. 26, figs. 2A–B; sample 321-1337A-4H-2 , 16–19cm; ECO-128; D11-4. (2) Pl. 26, figs. 4A–B; sample 321-1337A-4H-2 , 16–19cm; ECO-129; L12-2. (3) Pl. 26, figs. 3A–B; sample 321-1337A-7H- 6, 104–107cm ; ECO-134; T26-1. (4) Pl. 26, figs. 5A–B; sample 321-1337A-4H-2 , 16–19cm; ECO-128; U13-3. (5) [not figured] sample 321-1337A-7H- 6, 104–107cm ; ECO-134; R36-4 .

Measurements. Cephalis height 65–81 (74)μm; cephalis width 55–68 (63)μm; width of neck 49–56 (52)μm. Based on 9 specimens.

Etymology. Named for Arie, the large, benevolent yokai that comes from the sea to tell prophecies and ward off evil.

Range. Late Miocene—Late Pleistocene, EEP (Table 1).

Figures

FIGURE 1. Diagram illustrating the general skeletal morphology of Lophophaenidae, and terminology used in this manuscript. Dashed lines indicate spines that are not visible from the angle shown, as they extend into the skeleton. An example specimen of Lophophaena casperi n. sp. is included for comparison to the diagrams.

FIGURE 6. Internal skeletal structure of Arachnocorallium calvata (Haeckel, 1887) Petrushevskaya, 1971.

FIGURE 7. Internal skeletal structure of Arachnocorys umbellifera (Haeckel, 1862) Petrushevskaya, 1971.

FIGURE 10. Internal skeletal structure of Lithomelissa alkonost n. sp.