Heteromesus oryktus Cunha & Wilson 2006, sp. nov.

• Main Authors: Cunha, Marina R., Wilson, George D. F.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2006
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Malacostraca; Isopoda; Ischnomesidae; Heteromesus; Heteromesus oryktus; Greenland; North Atlantic
• Online Access: https://doi.org/10.5281/zenodo.5064428; http://treatment.plazi.org/id/EB65B41CFFAFE4336A4DFD9BD5AD9038

Heteromesus oryktus sp. nov. (Figs 24–25) Etymology Oryktos means "digger" (Greek, masculine) because this species was collected from mudstone burrows possibly made by the animals. Material examined Holotype: female (6.1 mm), North Atlantic: off West Greenland, canyon bordering the western margin of the Fylla Structural Complex, 63º14.1’N, 55º26.0’W, 18.Aug 2003, R / V Prof Logachev, TTR13 stn AT­457­GR, 2140 m (ZMUC CRU­9872) Paratype: male (5.7 mm), same data as holotype (ZMUC CRU­9873). Diagnosis Pereonites 1–3 with anterolateral denticulate spines; pereonites 1–4 with median and paired lateral denticulate spines arranged in dorsal rows. Pereonite 1 of male with paired lateral rook spines. Pereonite 5 in female length 2.2 width, in male 4.1 width. Pleotelson posterolateral margin anterior to uropods without spines or tubercles. Antennula with 5 articles altogether; article 3 length similar to article 4. Uropods in male length 0.45 length of pleotelson. Description Body length in female 6.1 mm; granular. Head in female length 0.60 width, with 1–2 pairs of simple spines, cuticular structure fine spinous granulations, lobe on ventrolateral margin absent in lateral view. Pereonite 1 in female width 0.20 total body length; with median simple spine, 2–3 pairs of dorsal simple spines, 1 pair of anterolateral simple spines, 2 pairs of lateral simple spines. Pereonite 2 in female with median simple spine, 2 pairs of dorsal rook spines, 2 pairs of lateral simple spines. Pereonite 3 in female with median simple spine, 2–3 pairs of dorsal simple spines, 1 pair of lateral simple spines. Pereonite 4 length 0.65 width; with 2 pairs of dorsal simple spines. Pereonites 1–4 in female with spines stout to short, denticulate and topped by setae; anterolateral spines decreasing in length from pereonite 1 to pereonite 3, length distinctly less than length of pereonite 1. Pereonite 5 in female length 0.25 total body length. Pereonite 5 with lateral row of setae. Pleotelson in female length 1.5 width. Antennula in female article 2 ...