Echinoderes riedli Higgins, 1966

Sørensen, Martin V., B, Maria Herranz, B, Fernando Pardos & B, Furkan Durucan, 2021, Kinorhynchs from sandy coastal habitats in Turkey, with the description of a new pan-Mediterranean species of Echinoderes (Cyclorhagida: Echinoderidae), Turkish Journal of Zoology 45 (7), pp. 526-549 : 537

3.3. New records of Echinoderes riedli Higgins, 1966

Figures 6A–6E

Material examined: A single female specimen collected from St. 3/4 (see Table 1 for station data). The specimen was mounted for LM, and deposited at NHMD under catalogue number NHMD-872891.

Notes on morphology, habitat and distribution: The species was originally described from Al-Ghardaqa, Egypt, in the Red Sea ( Higgins, 1966), and was later found and redescribed (with emphasis on information from juvenile stages) from Carthage, Tunisia, in the Mediterranean ( Higgins, 1978). The current record is the first reporting of the species since Higgins (1978).

The single specimen collected from Balıkesir, Ayvalık (St. 3/4) in the present study followed Higgins’ (1966, 1978) descriptions of E. riedli so closely that we believe this is the same species. The spine and tube patterns fit Higgins’ description, and even though all spines tend to be slightly longer in the Turkish specimen, the overall trunk dimensions, trunk appearance and shape of tergal extensionsfolloweddescriptions ( Figure 6F ).Theexamined specimen also suggests that E. riedli does not possess any previously overlooked tubes or glandular cell outlets type 2. The only noteworthy difference between the examined specimen and the redescription provided by Higgins (1978) regards the distribution of sensory spots/glandular cell outlets type 1. As in other early Higgins contributions, these cuticular structures tend to get confused with each other, and what Higgins (1978) reports as sensory spots are actually glandular cell outlets type 1. This is confirmed by the specimen from Balıkesir, which has a distribution of glandular cell outlets type 1 that perfectly (except for one deviation on segment 9) fits the described sensory spot pattern in E. riedli ( Higgins, 1978) . This suggests that E. riedli has following dorsal pattern of glandular cell outlets type 1: Middorsal outlets on segments 1 to 3, paradorsal outlets on segments 4 to 9 ( NB: Higgins (1978) reports the outlet/sensory spot on segment 9 as middorsal), and middorsal outlets on segments 10 and 11 ( Figures 6B and 6D ). This adds E. riedli to the group of echinoderids with the ‘ MD 1-3, PD 4-9 gco1 pattern’ (see Table 21 in SØrensen et al., 2020). Since E. riedli never previously was documented photographically, we are providing an LM plate ( Figures 6A–6E ) showing cuticular details and diagnostic characters for the species.

Figures

Figure 6. Light micrographs showing overviews and details of female Echinoderes riedli, NHMD-872891, from Balıkesir, Ayvalık, Turkey. (A) Ventral overview. (B) Segments 1 to 6, dorsal view. (C) Segments 1 to 6, ventral view. (D) Segments 6 to 9, dorsal view. (E) Segments 5 to 9, ventral view. (F) Segments 10 to 11, focusing on tergal extensions. Abbreviations: ltas, lateral terminal accessory spine; lvs, lateroventral spine; lvt, lateroventral tube; mdgco1, middorsal glandular cell outlet type 1; mds, middorsal spine; pdgco1, paradorsal glandular cell outlet; te, tergal extensions; vlt, ventrolateral tubes.