Echinoderes sublicarum Higgins, 1977

Sørensen, Martin V., Goetz, Freya E., Herranz, María, Chang, Cheon Young, Chatterjee, Tapas, Durucan, Furkan, Neves, Ricardo C., Yildiz, N. Özlem, Norenburg, Jon & Yamasaki, Hiroshi, 2020, Description, redescription and revision of sixteen putatively closely related species of Echinoderes (Kinorhyncha: Cyclorhagida), with the proposition of a new species group - the Echinoderes dujardinii group, European Journal of Taxonomy 730, pp. 1-101 : 49-50

Echinoderes sublicarum Higgins, 1977

Fig. 8C, F, I

Emended diagnosis

Echinoderes with middorsal spines on segments 4 to 8, and lateroventral spines on segments 6 to 9; middorsal spines on segments 5 to 8 extend well beyond the posterior margin of their respective segments. Tubes present in lateroventral positions on segments 2 and 5, and in laterodorsal positions on 10; tubes on segment 10 are long and slender. Minute glandular cell outlets type 2 in laterodorsal positions on segment 8. Tergal extensions of segment 11 pointed, with additional tooth on inferior margin. Females with ventromedial female papillae formed by crescentic substructure and a tube on segment 8; similar ventrolateral female papillae might also be present on segment 7.

Material examined

Holotype

SOUTH CAROLINA • 1 ♀; Georgetown, North Inlet Estuary, Clambank docks ; 33°20′ N, 079°11′ W; <1 m b.s.l.; 19 Mar. 1975; W. Sikora leg.; from the hydroid Eudendrium sp.; USNM-54397 . Specimen mounted for LM.

Paratypes

SOUTH CAROLINA • 4 ♀♀, 4 ♂♂; same collection data as for holotype; USNM-54399 to 54400 . Specimens mounted for LM .

Most of the types were in good condition, although the mounting medium was partly or fully dried out. While it was easy to see spines and tubes, it was very difficult or impossible to see the mostly subcuticular structures, such as glandular cell out type 1, female papillae and sensory spots. SEM specimens were not available. See Table 1 for an overview.

Description

The appearance of the species generally follows the description provided by Higgins (1977b), hence the following notes only provide additional information not included in the original description.

Males and females with minute laterodorsal glandular cell outlets type 2 on segment 8 ( Fig. 8C ). Spines and tubes as described by Higgins (1977b). Glandular cell outlets type 1 present in middorsal positions on segments 1 to 3, 10 (two longitudinally aligned) and 11, in subdorsal positions on segments 4 to 9, in sublateral positions on segment 1, and ventromedial positions on segments 2 to 10 (most of these structures are also included in the original description, but generally referred to as ‘sensory spots’).Actual sensory spots were only observed in paradorsal positions on segments 6 to 8, but more sensory spots are most likely present. Female papillae are present in ventromedial positions on segment 8 ( Fig. 8F ). The intracuticular substructures indicate the presence of a very weak crescentic line, and a more distinct tube extending from the centre of this line. Higgins (1977b) also reports these structures but refers to them as “bracket-shaped muscle scars”. He does not mention that they are restricted to females, but we can confirm that this is the case. Higgins (1977b) furthermore reports the present of “bracket-shaped muscle scars” in ventrolateral positions of segment 7. This suggests that female papillae also could be present on this segment. We cannot confirm their presence, but this is most likely due to the age and condition of the type specimens. Hence, based on own observations and information provided by Higgins (1977b) we find it likely that female papillae are present in ventrolateral positions of segment 7 and ventromedial positions of segment 8. Laterodorsal tubes on segment 10 are quite long and slender ( Fig. 8I ). Tergal extensions of segment 11 are well-spaced and pointed ( Fig. 8I ). Lateral terminal spines are regular acicular, and gradually tapered towards tips.

Figures

Fig. 8. Comparative light micrographs showing selected details of E. pacificus Schmidt, 1974. A. Holotype, ♀ (USNM-53335). D–G. Paratype (USNM-53336). B, E, H. E. kozloffi Higgins, 1977. Holotype, ♀ (USNM-53337). C, F, I. E. sublicarum Higgins, 1977. Paratype, ♀ (USNM-54399). A–C. Segments 8 to 9, dorsal view, showing presence of glandular cell outlets type 2 on segment 8. D–F. Segments 6 to 8, ventral view, position and appearance of sexually dimorphic female papillae. G–I. Segments 10 to 11, with midlateral tubes on segment 10, and lateral terminal spines.