Phylum: Annelida
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PHYLUM: ANNELIDA Authors Natasha Karenyi1 and Lara Atkinson2 Citation Karenyi N and Atkinson LJ. 2018. Phylum Annelida In: Atkinson LJ and Sink KJ (eds) Field Guide to the Ofshore Marine Invertebrates of South Africa, Malachite Marketing and Media, Pretoria, pp. 121-132. 1 University of Cape Town, Centre for Statistics, Environment and Conservation, Department of Biological Sciences 2 South African Environmental Observation Network, Egagasini Node, Cape Town 121 Phylum: ANNELIDA Polychaetes Polychaetes are segmented worms that are other species. Many tube worms are sedentary and easily identiiable by their leshy lobes projecting ilter feed by means of specialised cilia. They are from each segment called parapodia (‘feet’). The short-lived, having annual, or shorter, life spans, parapodia bear many bristles (chaetae) that are however, their tubes and the habitat they create used for movement, hence their common name of can be long-lived. Polychaetes provide an important bristle worms. Important diagnostic features when source of food for many deep-sea predators identifying polychaetes include the head, mouth including ish. parts, parapodia and chaetae. Collection and preservation More than 17 000 annelid species have been Polychaete specimens should be placed in 10% described, with approximately 800 polychaete bufered formalin for 24 hours before preserving species recorded in South Africa. in 96% ethanol. For genetic or molecular studies, specimens should be placed directly in 96% ethanol, These organisms are robust and occur in highly which should be changed after 24 hours. If necessary, variable conditions including extreme habitats specimens can be relaxed using 7% MgCl₂ solution such as hydrothermal vents and the deepest parts or sparkling water (over several hours) and then of the ocean. Polychaetes can range in length from transferred to 10-30% ethanol before preservation less than ten millimetres to nearly three metres and to allow the proboscis to expand. can occur in numerous colours (even iridescent or luminescent). Specimens should be handled with care. Fine-tip steel forceps should be used to place specimens into Polychaetes are highly adaptable and can create or containers to avoid damage to the soft diagnostic inluence habitat structure by burrowing or building features. tubes, which often provide attachment for many References Campbell NA, Reece JB and Mitchell LG. 1999. Biology (5th Ed.) Benjamin-Cummings Publishing Company Inc. Menlo Park, CA. Day JH. 1967. A Monograph on the Polychaeta of Southern Africa. Trustees of the British Museum (Natural History), London. 878pp. Raven PH and Johnson GB. 2002. Biology (6th Ed.), Chapter 45: Mollusks and Annelids. The McGraw Hill Companies, Boston. Rouse GW and Fauchald K. 1998. Recent views on the status, delineation, and classiication of the Annelida. American Zoologist 38 (6): 953–964.doi:10.1093/icb/38.6.953. Tracey DM, Anderson OF and Naylor JR. 2011. A guide to common deepsea invertebrates in New Zealand waters. New Zealand Aquatic Environment and Biodiversity Report No. 86. 317pp. 122 Phylum: Annelida Annelid (polychaete) general body plan (General FB code PolW): Jaws Parapodia (feet) Proboscis Antennae Chaetae Head (bristles) Tentacles Eye Tentacles Proboscis Jaws Body segments Family: Nereidae Genus: Nereis Anus External features anterior end Head Elytra (scales) Chaetae Body segments Parapodia Anus Family: Aphroditidae 123 Phylum: Annelida Chloeia inermis (Euphr1) Phylum: Annelida Class: Polychaeta Subclass: Errantia Order: Amphinomida Family: Amphinomidae Genus: Chloeia Species: inermis Common name: Bristle worm 40 mm 64 mm Distinguishing features Size Body fairly leshy and irm, dorso-ventrally lattened Up to 60 mm in length. and broadly oval. Long, pale yellow chaetae (bristles) along outer ventral edge, with shorter chaetae along Distribution mid-latero dorsal surface. Smooth segmented ventral West and South Coasts of South Africa. side (± 30 segments). Mouth parts may extrude in a bulbous type ‘head’. Branched gill pairs (branchiae) Similar species visible from segment four in mid-dorsal region (red Several large bristle worms occur in South African in colour). Bristles can break of into hands/ingers waters. Chloeia genus fairly distinct as described. and be slightly irritating, but not poisonous or C. inermis has no distinct colour pattern on the dorsal dangerous. Large catches of this species sometimes surface. occur. Reference Colour Day JH. 1967. A Monograph on the Polychaeta of Pale pink to dark brown with yellow bristles. Southern Africa. Trustees of the British Museum Protruding mouth parts red in colour. (Natural History), London. pp 123-125. (878pp.). 124 Phylum: Annelida Hyalinoecia tubicola (QuilWm) Phylum: Annelida Class: Polychaeta Subclass: Errantia Order: Eunicida Family: Onuphidae Genus: Hyalinoecia Species: tubicola Common name: Quill worm 40 mm 148 mm Distinguishing features Distribution Quill worms live inside inlexible straw-like tubes, West Coast of South Africa as far as Cape Agulhas frequently caught in research trawls. Long, thin body in south. shape with numerous rectangular segments. Three long antennae visible on head. Parapodia (feet) Similar species clearly visible, with ine chaetae (bristles) projecting. None – straw-like tubes are distinctive. NOTE: Even if only empty tubes are present, this Reference species must still be recorded with a note explaining Day JH. 1967. A Monograph on the Polychaeta of that only empty tubes were present under FishBoard Southern Africa. Trustees of the British Museum code ‘PolTub’. (Natural History), London. pp 411-412. (878pp.). Colour Pale pink to brown, with iridescent sheen. Size Can be up to 120 mm in length, but segments often break apart. 125 Phylum: Annelida Aphrodita alta (AphrSp) Phylum: Annelida Class: Polychaeta Subclass: Errantia Order: Phyllodocida Family: Aphroditidae Genus: Aphrodita Species: alta Common name: Sea mouse 38 mm 40 mm Distinguishing features Distribution Large polychaete species with irm, solid, leshy Mostly West Coast, but can occur along South Coast. texture. Body oval, arched dorsally, tapering posteriorly, with 35-45 segments bearing 15 pairs Similar species of scales (elytra). Usually curls into a circular or semi- Euphione elisabethae, but Aphrodita alta scales not circular shape. Dorsal surface covered with many as rigid and body is more oval-shaped. plates and ine hairs. Strong, stout bristles projecting along margin of dorsal and ventral surfaces. Dorsal Reference surface brown and often coated in ine mud. Ventral Day JH. 1967. A Monograph on the Polychaeta of surface pale pinkish-white colour. Southern Africa. Trustees of the British Museum (Natural History), London. p. 35. (878pp.). Colour Dorsal surface brown (muddy), ventral surface pale pink. Size Up to 60 mm in length. 126 Phylum: Annelida Laetmonice benthaliana (Aphro2) Phylum: Annelida Class: Polychaeta Subclass: Errantia Order: Phyllodocida Family: Aphroditidae Genus: Laetmonice Species: benthaliana Common name: Naked scale worm 32 mm 32 mm Distinguishing features Distribution Oval-bodied polychaete with very thin, transparent West and South Coasts, mostly in deeper waters scales covering the dorsal surface. Stout bristle along shelf edge. encased in each parapodia (foot), with long ilamentous yellow chaetae (bristles) projecting Similar species along dorso-lateral edge. Ventral surface clearly Similar to scale worm Euphione elisabethae, but segmented, pale yellow in colour. Body leshy, scales of Laetmonice benthaliana have no tubercles lexible and soft. and are soft and transparent. Colour Reference Pale pink, brown to yellow in colour. Day JH. 1967. A Monograph on the Polychaeta of Southern Africa. Trustees of the British Museum Size (Natural History), London. p. 33. (878pp.). 40–60 mm in length. 127 Phylum: Annelida Euphione elisabethae (Aphro1) Phylum: Annelida Class: Polychaeta Subclass: Errantia Order: Phyllodocida Family: Aphroditidae Genus: Euphione Species: elisabethae Common name: Scale worm Scales with Head and tubercles mouth parts Parapodia 33 mm 33 mm Distinguishing features Distribution Ventrally lattened species, with very clearly deined South African endemic. West and South Coasts of scales along dorsal surface that completely cover the South Africa. stoutly bristled parapodia (feet). Scales have small tubercles covering their surface. Ventral surface soft Similar species and segmented. Head, tentacles and mouth parts Laetmonice benthaliana looks similar, but does not clearly visible. have tubercles on dorsal scales. Colour Reference Pale brown on dorsal surface and pink to white on Day JH. 1967. A Monograph on the Polychaeta of ventral surface. Southern Africa. Trustees of the British Museum (Natural History), London. p. 77. (878pp.). Size Up to 70 mm in length. 128 Phylum: Annelida Macellicephala mirabilis (MacMir) Phylum: Annelida Class: Polychaeta Subclass: Errantia Order: Phyllodocidae Family: Polynoidae Genus: Macellicephala Species: mirabilis Common name: Purple scale worm 16 mm 16 mm Distinguishing features Distribution Body short (18 segments). Extending from the Recorded from the West Coast of South Africa. head is a very long middle antenna ending in a Further distribution uncertain. bulb. Although this is a scale worm, the scales are deciduous, therefore not always present. First few Similar species parapodia projecting forward. Several large scale worms occur in South African waters. The Macellicephala genus is fairly distinct Colour due to its colour and deciduous