Boroecia hopcrofti Stępień & Błachowiak-Samołyk & Krawczuk & Angel 2018, new species

• Main Authors: Stępień, A., Błachowiak-Samołyk, K., Krawczuk, M., Angel, M. V.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2018
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Ostracoda; Halocyprida; Halocyprididae; Boroecia; Boroecia hopcrofti; Arctic; Gulf of Alaska; Zooplankton; Alaska
• Online Access: https://zenodo.org/record/5958709; https://doi.org/10.5281/zenodo.5958709

2.6. Boroecia hopcrofti new species (Figures 16–18) Etymology. The species is named after Professor Russ Hopcroft, both in recognition of his considerable contributions to the study of zooplankton especially in the Arctic, and for facilitating our studies of the halocyprids from the Canadian Deep and from the Gulf of Alaska. Type locality. Holotype: A male 2.64 mm long, dissected, stained with lignin pink and mounted on slides. Collected at Healy 0 502 station 13, 15th July 2005 at the type locality 75°15.8’N, 161° 12’W; depth 750– 500 m. Deposited at the Natural History Museum London NHMUK2016-628. Paratype: A female 2.76 mm long, dissected, stained with lignin pink and mounted on slides. Collected in the same samples as the holotype. Museum registration number NHMUK 2016-629. The other material examined is listed in Appendix 1. Male. Carapace (Figures 16 A,B). The length is 2.67 ± 0.069 mm (Table 1), the height, that is 40.0% CL is only slightly greater than the width (38.4% CL). The lateral outline is sub-rectangular with little or no anterior taper. The shoulder vaults are rounded and not strongly developed. In ventral view, the maximum width is just posterior to mid-length, and the anterior margin of the carapace below the incisure is slightly flanged. The rostrum, measured from the anterior end of the hinge between the valves, is 11–12% CL, which is slightly longer than the depth of the incisure (~8% CL). The left asymmetrical gland (LAG) opens just anterior to the posterior end of the carapace hinge (~4% CL) and twice that distance from the posterior margin of the carapace. The right asymmetrical gland (RAG) opens slightly above PVC (30–31% CL below the hinge-line). There is a group of lateral edge glands on both valves just dorsal to the RAG. The posterior dorsal corner of the carapace forms a rounded right angle on both valves, and lacks spines, although on the left valve there is a slight process that may be a residual spine. Beneath the incisure on the anterior flanks of the carapace are clear oblique ...