Aphelochaeta hormosa Blake 2018, new species

• Main Author: Blake, James A.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2018
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Terebellida; Cirratulidae; Aphelochaeta; Aphelochaeta hormosa; Antarc*; Antarctica; East Antarctica
• Online Access: https://doi.org/10.5281/zenodo.3798624; http://treatment.plazi.org/id/03A2CB16FFECA256FF36F9AAFC66FC98

Aphelochaeta hormosa new species Figures 11–12 Material examined. East Antarctica, Budd Coast, Wilke’s Station, coll. Virginia Institute of Marine Science, 03 Dec 1961, 66.354°S, 110.468°E to 66.354°S, 110.471°E, dredged, 238 m, holotype (USNM 1490710) and 2 paratypes (USNM 1490711). Description. Holotype complete, broken into three parts, 16.4 mm long, 0.45 mm wide across expanded thoracic region, 0.145 mm across middle segments, with 97 setigerous segments. Holotype with anterior or thoracic segments expanded both dorsally and ventrally (Figs. 11A, 12A), more or less oval in cross section with narrow crowded segments; abdominal region with moniliform segments each about 1.5 times long as wide (Figs. 11B, 12B); posterior segments becoming narrow, wider than long, producing weakly expanded posterior end rounded dorsally, flattened ventrally with low ridge, then tapering to simple rounded pygidial lobe (Figs. 11C, 12C). Body tan in color; holotype with black pigment spots on dorso-lateral margins of peristomium (Fig. 11A). Prostomium conical, tapering to narrow rounded tip (Figs. 11A, 12A); eyespots absent, nuchal organs narrow lateral slits; dorsal crest not apparent. Peristomium broad, with three annular rings best seen laterally on holotype (Figs. 11A, 12A), only weakly observed on paratypes; relatively smooth dorsal surface not cut with annular rings, ventrally forming lips around of mouth. Pair of dorsal tentacles arising medially in notch on posterior margin of peristomium (Fig. 11A); first pair of branchiae arising lateral and slightly posterior to dorsal tentacles (Fig. 11A); subsequent branchiae on setiger 1 and following segments dorsal to notosetae, continuing through expanded thoracic segments, not observed on abdominal segments. Parapodia best developed in thoracic segments, inflated but weakly developed, consisting of low setal tori bearing fascicles of 8–10 thin, smooth capillaries in single row; parapodia of abdominal segments not evident, with 3–4 capillaries arising directly from body wall (Fig. ...