Echinoderes undetermined
Creators: name: Grzelak, Katarzyna
name: Sørensen, Martin V.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Kinorhyncha
Cyclorhagida
Echinorhagata
Echinoderidae
Echinoderes
Echinoderes undetermined

description: Echinoderes sp. aff. E. galadrielae / E. beringiensis
Fig. 32; Table 20
Material examined
NEW ZEALAND • 1 ♀; Hikurangi Slope, stn TAN1004/4; 41.6837° S, 175.6642° E; 1046 m b.s.l.; Apr. 2010; NIWA TAN1004 Voyage; soft sediment; NIWA-159427. Mounted for LM in Fluoromount G on glass slide • 2 ♂♂; Hikurangi Slope, stn TAN1004/38; 41.5937° S, 175.8532° E; 1121 m b.s.l.; Apr. 2010; NIWA TAN1004 Voyage; soft sediment; personal reference collection of MVS. Mounted for SEM • 1 ♀; Hikurangi Slope, stn TAN1004/76; 41.6833° S, 175.6500° E; 1282 m b.s.l.; Apr. 2010; NIWA TAN1004 Voyage; soft sediment; NHMD-921503. Mounted for LM in Fluoromount G on HS slide • 1 ♂; same collection data as for preceding; personal reference collection of MVS. Mounted for SEM • 1 ♀, 1 ♂; Pahaua Canyon, stn TAN1004/12; 41.5508° S, 175.7250° E; 1350 m b.s.l.; Apr. 2010; NIWA TAN1004 Voyage; soft sediment; NHMD-921498 to 921499. Mounted for LM in Fluoromount G on glass slides • 2 ♂♂; Pahaua Canyon, stn TAN1004/27; 41.4983° S, 175.7043° E; 1013 m b.s.l.; Apr. 2010; NIWA TAN1004 Voyage; soft sediment; personal reference collection of MVS. Mounted for SEM • 1 ♂; Honeycomb Canyon, stn TAN1004/53; 41.4563° S, 175.8970° E; 948 m b.s.l.; Apr. 2010; NIWA TAN1004 Voyage; soft sediment; NHMD-921500. Mounted for LM in Fluoromount G on glass slide • 1 ♂; Honeycomb Canyon, stn TAN1004/58; 41.4080° S, 175.8977° E; 1171 m b.s.l.; Apr. 2010; NIWA TAN1004 Voyage; soft sediment; NHMD-921502. Mounted for LM in Fluoromount G on HS slide • 1 ♀; Seamount 310, stn TAN1004/69; 41.3353° S, 176.1882° E; 670 m b.s.l.; Apr. 2010; NIWA TAN1004 Voyage; soft sediment; NHMD-921501. Mounted for LM in Fluoromount G on glass slide.
Distribution
Hikurangi Margin, from slope, through canyon, and seamount habitats, 670–1350 m b.s.l. See Fig. 1 for a geographic overview of stations and Table 1 for station and specimen information.
Brief description and remarks
The examined specimens closely follow the morphology of E. galadrielae sp. nov. in terms of distribution of spines, tubes, glandular cell outlets, and even the middorsal division of the tergal plate of segment 11. However, E. galadrielae and E. aff. E. galadrielae / E. beringiensis differ at two important points, i.e., spine morphometrics (see Table 20) and the shape of the tergal extensions (compare Figs 30A, 31D, I with Fig. 32). Middorsal spines were in general longer in this current set of specimens, while the lateroventral ones were shorter than in E. galadrielae. The unidentified specimens have also markedly longer lateral terminal spines, which in most cases exceed the trunk length, resulting in markedly higher LTS/TL ratio in this species compared to E. galadrielae (average LTS/TL: 106% vs 87%, respectively). The most conspicuous difference between E. galadrielae and these unidentified specimens is expressed in the tergal extensions, which are exceptionally long in E. galadrielae (Figs 29–31). This stands in strong contrast to the short, triangular tergal extensions in the unidentified specimens (Fig. 32). These tergal extensions are much more similar to those in E. beringiensis as well as many other species of Echinoderes.
We would, on the other hand, hesitate in identifying the specimens as E. beringiensis, since they differ in the distribution of sensory spots and lack the midlateral glandular cell outlets type 2 that characterizes females of E. beringiensis (see Adrianov & Maiorova 2022). In addition, E. beringiensis has a longer trunk (TL: 331 µm vs 208 µm, respectively) and has proportionally shorter lateral terminal spines (LTS/TL: 50% vs 106%, respectively). In conclusion, these enigmatic specimens appear to represent an intermediate between E. galadrielae sp. nov. and E. beringiensis, and it would require a molecular comparison to unveil their true identity.
description: Published as part of Grzelak, Katarzyna & Sørensen, Martin V., 2022, Echinoderes (Kinorhyncha: Cyclorhagida) from the Hikurangi Margin, New Zealand, pp. 1-108 in European Journal of Taxonomy 844 on pages 81-82, DOI: 10.5852/ejt.2022.844.1949, http://zenodo.org/record/7222155