Arachnocorys spinosissima ( Tan and Tchang, 1976 ) 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 : 22

Arachnocorys spinosissima ( Tan and Tchang, 1976) n. comb.

Plate 6, Figs. 1A – 4B .

Lithomelissa spinosissima n. sp., Tan and Tchang, 1976, pl. 68, figs. 50a–e.

Lithomelissa spinosissima Tan and Tchang, Tan and Su, 2003 , text-fig. 108.

Lithomelissa spinosissima Tan and Tchang, Aita et al., 2009 , pl. 5, figs. 6a–c.

? Lithomelissa spinosissima Tan and Tchang, Trubovitz et al., 2020 , supplementary data 7.

unknown plagonid group C sp 58, Trubovitz et al., 2020, supplementary data 7.

Remarks. Tan and Tchang (1976) originally assigned this species to Lithomelissa but we are of the opinion that L. spinosissima does not fit the definition of Lithomelissa due to the apical spine running along the wall of the cephalis rather than passing freely through it. Tan and Tchang (1976) did not provide a discussion of the rationale for their genus assignment, and the only differential diagnosis was with the species Lithomelissa thoracites . L. thoracites has since been transferred to the genus Peromelissa , so it is problematic to keep L. spinosissima within Lithomelissa for multiple reasons. Here we propose that this species should be transferred to Arachnocorys due to similarities with A. pentacantha , namely the segment proportions, arches connecting the cephalis and thorax, and positioning of the apical spine.

Range. Late Miocene—Recent 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 4. Examples of specimen measurements discussed in the Systematic Paleontology section of this study.