Botryopera bolotniki, 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 : 26-27

Botryopera bolotniki n. sp.

Plate 8, Figs. 1A – 6B .

urn:lsid:zoobank.org:act:A713A6DA-F8AC-4111-BBFA-731495FC4DA7

unknown plagonid group C sp 51 cf, Trubovitz et al., 2020, supplementary data 7.

Diagnosis. Small lophophaenid with similarities to Botryopera , including a narrow cephalis and subcylindrical shell outline, but in addition has strong conical dorsal, lateral and apical spines, often with distinctly thickened tips.

Description. This species is overall subcylindrical in shape, with a small and narrow thumb-shaped cephalis and a slightly wider thorax. The apical spine is fused to the wall of the cephalis and extends upward as a distinct conical spine with a thickened tip. The thorax attaches to the bottom third of the cephalis with several small lobes. The dorsal and lateral spines extend outward from the thorax as conical spines with thickened tips, closely resembling the characteristics of the apical spine. The cephalis is slightly more heavily silicified than the thorax, but both segments are relatively thin compared to other Botryopera species. This species has a short, thin, dendritic axobate, which is not always preserved in every specimen. The specimen in figure 5 is aberrant, with a deformity that apparently caused the growth of two apical spines.

Remarks. This species closely resembles Botryopera amabie n. sp. (Pl. 7, Figs. 1 A-6), except that it has a thinner shell wall throughout the skeleton, more consistent pore sizes, and long, conical dorsal, lateral, and apical spines that are usually thickened at their tips, resembling cotton swabs. Transitional forms between the two species were not observed, and their ranges do not overlap, suggesting that they may be separate but related species. The genus designation was tentatively made due to the overall shell proportions and presence of an axobate, which would likely exclude it from Lophophaena and make Botryopera the best fit, despite this genus being poorly defined.

Material examined. 15 specimens observed from samples 321-1337D-23H- 6, 134–137cm (Late Miocene), 321-1337A-16H- 6, 121–124cm (Late Miocene), 321-1337A-14H-7, 39–42cm (Late Miocene), and 321-1337A-10H-2, 91–94cm (Early Pliocene).

Holotype. Pl. 8, Figs. 1A–B ; sample 321-1337A-14H-7 , 39–42cm; ECO-138; F36-4.

Paratypes. (1) Pl. 8, figs. 2A–B; sample 321-1337A-14H-7, 39–42cm; ECO-138; D30-1. (2) Pl. 8, figs. 3A–B; sample 321-1337A-14H-7, 39–42cm; ECO-140; M12-3. (3) Pl. 8, figs. 6A–B; sample 321-1337A-14H-7, 39–42cm; ECO-140; T27-2 . (4) Pl. 9, figs. 4A–B; sample 321-1337A-14H-7, 39–42cm; ECO-139; Y34-3. (5) Pl. 8, figs. 5A–B [deformed specimen]; sample 321-1337A-14H-7, 39–42cm; ECO-138; S33-3. (6) [not figured] sample 321-1337A-14H-7, 39–42cm; ECO-138; N10-4. (7) [not figured] sample 321-1337A-14H-7, 39–42cm; ECO-140; Z14-4 .

Measurements. Cephalis height 31–34 (32)μm; cephalis width 25–26 (26)μm; neck width 23–25 (24)μm; shoulder width 28–35 (32)μm. Based on 9 specimens.

Etymology. Named for the swamp spirit, bolotnik, in Slavic folklore.

Range. Late Miocene—earliest Pliocene in the 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.