Higginsarctus alatus (Gomes-Júnior, E. Santos, da Rocha, P.J.P. Santos & Fontoura, 2018) Hansen & Kristensen, 2021

Hansen, Jesper G. & Kristensen, Reinhardt M., 2021, A new genus and five new species of the subfamily Florarctinae (Tardigrada, Arthrotardigrada), European Journal of Taxonomy 762 (1), pp. 149-184 : 178

Higginsarctus alatus (Gomes-Júnior, E. Santos, da Rocha, P.J.P. Santos & Fontoura, 2018) gen. et comb. nov.

Figs 17–18

Amended diagnosis (characters uniquely defining the taxon are written in bold)

Characterized by flat, bilobed secondary clavae. Unilobed, rectangular antero-lateral alae with weakly undulating distal margins without indentations. Unilobed, rectangular medio-lateral alae with weakly undulating distal margins without indentations. Antero-lateral alae and medio-lateral alae similar in size. Bilobed postero-lateral alae with a medial arched identation. Postero-lateral alae larger than antero-lateral alae and medio-lateral alae. Bilobed, rectangular caudal ala with deep arched identation medially. Lobes of the caudal ala nearly rectangular. Leg sense organs I–III highly different in length. Genital stoup present. Duct openings of seminal receptacles with true papillae.

Material examined

Holotype BRAZIL • Southwestern Atlantic Ocean, Potiguar Basin , Rio Grande do Norte State; 04°37′ S, 36°45′ W; depth 150 m; 2009; bioclastic and lithoclastic sand; P. Fontoura (C. VII-84).

Paratype BRAZIL • 1 spec.; same collection data as for holotype; P. Fontoura (C. VII-87) .

Remarks

The results of our examination of the species described as Ligiarctus alatus confirm the presence of large, rigid and backwards bending primary clavae supported by strong internal cuticular structures at their bases, proximal part of the alae internally supported by procuticle which sends out branching processes (ramuli) into the distal part of the alae, and all claws with a small internal notch. Furthermore, it is evident that this species has three pairs of lateral alae. Thus, conforming to the diagnosis of Higginsarctus gen. nov., the species is here transferred to the new genus as Higginsarctus alatus gen. et comb. nov. In addition, our observations revealed the presence of a genital stoup ( Figs 17B , 18A ) and genital papillae ( Figs 17B , 18A ). We were also able to determine the shape of the secondary clavae ( Figs 17A , 18B ). As a consequence of the new information attained, the diagnosis of Higginsarctus alatus gen. et comb. nov. is amended accordingly.

Ecology and distribution

Known only from the type locality.

Figures

Fig. 17. Higginsarctus alatus (Gomes-Júnior, E. Santos, da Rocha, P.J.P. Santos & Fontoura, 2018) gen. et comb. nov. A. Paratype (C.VII-87). Close up on the head, ventral view showing the cephalic cirri and secondary clavae. B. Holotype (C.VII-84). Close up on the caudal region, ventral view showing the gonopore, genital stoup, anus and seminal receptacles with genital papillae. Abbreviations: see Material and methods. Drawing by Stine B. Elle.

Fig. 18. Higginsarctus alatus (Gomes-Júnior, E. Santos, da Rocha, P.J.P. Santos & Fontoura, 2018) gen. et comb. nov. A. Holotype (C.VII-84). Close up on the caudal region, ventral view showing the gonopore, genital stoup, anus and genital papillae. B. Paratype (C.VII-87). Close up on the secondary clava. Abbreviations: see Material and methods.