taxonID	type	description	language	source
CE19ECA5D74E5865913930C34E6E3278.taxon	type_taxon	Type species. Nereis sanguinea Montagu, 1813.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
CE19ECA5D74E5865913930C34E6E3278.taxon	diagnosis	Diagnosis (after Molina-Acevedo and Carrera-Parra 2017). Prostomium slightly or completely bilobed; five prostomial appendages without articulations; eyes present or absent. Peristomium without peristomial cirri. Maxillary apparatus with four pairs of maxillae, an unpaired on the left side; MI with falcal arch developed, extended, with the outer edge of the base arched; MIII curved, forming part of distal arc, with attachment lamella of rectangular or irregular shape, situated at centre of posterior edge of maxilla; MIV with circular or rectangular attachment lamella. Branchiae distributed along entire body. Dorsal cirri without articulation; postchaetal lobe well developed in anterior region. Ventral cirri with swollen, oval, or circular base. All sub-aciculae dark. Supracicular chaetae include limbate, pectinate isodont chaetae with slender teeth, pectinate anodont chaetae with long teeth. Subacicular chaetae include compound falcigers or spinigers, or only limbate chaetae. Subacicular hook dark or translucent, bidentate or unidentate. Pygidium with two pairs of anal cirri, without articulation.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
02B523B8A84257E99251CBE50DFBBA48.taxon	description	Figs 1, 2, 14, 15, 16	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
02B523B8A84257E99251CBE50DFBBA48.taxon	diagnosis	Diagnosis. Prostomium completely bilobed, five prostomial appendages without articulations; eyes absent. Peristomium without Peristomial cirri. Maxillary apparatus with four pairs of maxillae, an unpaired on the left side, MI with falcal arch extended at sub-right angle, basal outer edge arched, basal inner edge lacking curvature. MII with triangular teeth and without attachment lamella. MIII slightly curved, with equal-sized triangular teeth, without attachment lamella. MIV with curved attachment lamella. Branchiae distributed along entire body. Dorsal cirri without articulations; postchaetal lobe well developed in anterior regions. Ventral cirri with swollen, inflated base. Sub-aciculae black, blunt, and translucent at distal end, pale brown in posterior-most parapodia. Supra-acicular chaetae include limbate, pectinate, thin, narrow isodont with short and slender inner teeth, pectinate thin, narrow heterodont with short and slender inner teeth, pectinate thick, wide isodont with long or short and slender inner teeth, and pectinate thick, wide anodont with long and slender inner teeth. Subacicular chaetae include limbate and compound spinigers. Subacicular hook bidentate. Pygidium with two pairs of anal cirri, without articulation.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
02B523B8A84257E99251CBE50DFBBA48.taxon	description	Description (based on holotype, with variation in parentheses for paratypes). Preserved specimens beige (Fig. 14 A), ~ 195 (66 – 401) chaetigers and 52 mm (20 – 91 mm) long, L 10: 4.5 mm (2.25 – 6.3 mm), W 10: 2.85 mm (1.2 – 3.75 mm), excluding parapodia. Anterior region of body cylindrical, with shallow groove until median chaetigers (Fig. 14 A); body depressed from chaetiger 30, elongated, and tapering at distal end. Live specimens red (Fig. 16 C). Prostomium conically bilobed, with two dorsoventrally lobes separated by an anterior notch (Fig. 14 A, B). Prostomial appendages in a semicircle, median antennae separated by a gap. Palps, lateral and median antennae reaching first peristomium. Palpophores and ceratophores ring-shaped, short, and thin; palpostyles and ceratostyles tapering and slender. Prostomial appendage peduncles absent. Peristomium wider than prostomium; first ring 3 × longer than second ring, separation between rings distinct on all sides. Maxillae pale brown (Fig. 14 C) and maxillary formula as follows: MF = 1 + 1, 6 (5 – 6) + 7 (6 – 7), 7 (7 – 8) + 0, 4 + 10 (9 – 10), 1 + 1. Maxillary carrier ~ 2.2 × shorter than MI, rectangular anteriorly, triangular posteriorly. MI forceps-like, without attachment lamellae, falcal arch extended at sub-right angle, basal outer edge arched, basal inner edge lacking a curvature. Closing system is ~ 5.5 × shorter than MI. Ligament between MI and MII pale brown. MII without attachment lamella, teeth triangular, present on <1 / 2 of plate length. Ligament between MII and MIII pale brown. MIII single, longer than left MIV, slightly curved, with equal-sized triangular teeth, without attachment lamella. Left MIV short (<1 / 2 the size of right MIV) with curved attachment lamellae. Right MIV long, with teeth triangular and curved attachment lamellae, decreasing in size and teeth curved posteriorly. MV paired. Mandibles whitish with pale brown core, longer than MI; cutting longer than MI; cutting plates whitish (Fig. 14 D). First few parapodia inserted ventrolaterally, but then becoming lateral in anterior region and dorsolaterally in subsequent segments. Chaetal lobes rounded on all chaetigers (Fig. 14 F – H). Prechaetal lobe shorter than chaetal lobe along the entire body. Postchaetal lobe rounded and longer than chaetal lobe in anterior chaetigers and mid-body onwards (Fig. 14 F – H), becoming shorter and absent in the posterior-most chaetigers. Dorsal cirri digitiform and slender, longer than ventral cirri anteriorly, as long as or shorter from mid-body and shorter in posterior chaetigers (Fig. 14 F – H). Ventral cirri digitiform in first chaetigers, basally inflated with digitiform tip from chaetiger six onwards (Fig. 14 F – H). Branchiae pectinate, starting from chaetiger 20 (11 – 65) and continuing to near end (~ 13 last chaetigers without branchiae), branchial filament 3 × longer than dorsal cirri where best developed; number of filaments increasing from one anteriorly to eight in mid-body, decreasing to six in last several chaetigers. Pygidial cirri attached to ventral side of pygidium, dorsal pair ~ 4 × longer than ventral (Fig. 14 I). Notoaciculae absent. Neuroaciculae black, blunt, and translucent at distal end along most of body, pale brown in posterior-most parapodia; ~ 3 or 4 per parapodium in anterior, one or two per parapodium in median and one per parapodium in posterior chaetigers (Fig. 14 F – H). Supra-acicular chaetae with limbate capillaries and pectinates. Five types of pectinate chaetae were identified (types 1, 3, 4, 5, 7) (see Fig. 2): type 1: thin, narrow isodont with 12 – 15 short and slender inner teeth, present in anterior and median region (Fig. 15 A); type 3: thin, narrow heterodont with 12 short and slender inner teeth, outer teeth longer on one side, present in the anterior body region (Fig. 15 B); type 4: thick, wide isodont with 18 – 29 short and slender teeth, outer teeth different length to inner teeth, only present in median and posterior region (Fig. 15 C – F): type 5: thick, wide isodont with 15 – 18 long and slender inner teeth, present only posteriorly (Fig. 15 E, F); type 7: thick, wide anodont with ~ 15 long and slender inner teeth, only present in posterior parapodia (Fig. 15 F). Subacicular chaetae with compound spinigers and limbate capillaries in median and posterior chaetigers. Some limbate chaetae with inconspicuous serrations and numerous projections (Fig. 15 G). Subacicular hooks pale brown, translucent at distal end, from chaetiger 22 (22 – 46), 1 – 3 per parapodium; subacicular hooks bidentate present throughout (Fig. 14 E). Pygidium with crenulated margin, with two pairs of tapering pygidial cirri attached to ventral side of pygidium, dorsal pair ~ 4 × longer than ventral one (Fig. 14 I).	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
02B523B8A84257E99251CBE50DFBBA48.taxon	etymology	Etymology. Name refers to the type locality Kuala Ibai River.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
02B523B8A84257E99251CBE50DFBBA48.taxon	distribution	Distribution. Known only from the type locality.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
BF9FE410DC1E56E49E0865806C6310C6.taxon	description	Figs 1, 2, 5, 6, 7	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
BF9FE410DC1E56E49E0865806C6310C6.taxon	diagnosis	Diagnosis. Prostomium completely bilobed, five prostomial appendages without articulations; eyes absent. Peristomium without peristomial cirri. Maxillary apparatus with four pairs of maxillae, an unpaired one on the left side, MI with falcal arch extended at sub-right angle, basal outer edge arched, basal inner edge lacking curvature. MII with triangular teeth and without attachment lamella. MIII slightly curved, with equal-sized triangular teeth, without attachment lamella. MIV with dark and curved attachment lamella. Branchiae distributed along entire body. Dorsal cirri without articulations; postchaetal lobe well developed in anterior regions. Ventral cirri with swollen, inflated base. Sub-aciculae black, blunt and translucent at distal end, pale brown in posterior-most parapodia. Supra-acicular chaetae include limbate, pectinate thin, narrow and wide isodont with short and slender inner teeth, and pectinate thick, wide isodont with short and slender inner teeth. Subacicular chaetae include only limbate chaetae. Subacicular hook absent. Pygidium with two pairs of anal cirri, without articulation.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
BF9FE410DC1E56E49E0865806C6310C6.taxon	description	Description (based on holotype, with variation in parentheses for paratypes). Preserved specimens beige (Fig. 5 A), with 518 (135 – 578) chaetigers, ~ 413 mm (173 – 295) total length, 12 mm (6 – 10.8) in length to chaetiger 10 (L 10), 4.8 mm (3.15 – 5.1 mm) width at chaetiger 10 (W 10), excluding parapodia. Body with dorsum convex and flat ventrum (Fig. 5 A), without groove; body elongated, rounded in cross-section at anterior and median regions, and dorsoventrally flattened thereafter. Live specimens red (Fig. 7 D). Prostomium bilobed, anteriorly rounded with two dorsoventrally flattened lobes separated by an anterior notch between (Fig. 5 B). Prostomial appendages in a semicircle, median antennae separated by a gap (Fig. 5 B). Palps reach to first ring of peristomium; lateral and median antennae to second ring of peristomium. Palpophores and ceratophores are ring-shaped, short, thin; palpostyles and ceratostyles tapering and slender. Prostomial peduncles absent. Peristomium larger and wider than prostomium; first ring 3 × longer than second ring, separation between rings distinct on all sides. Maxillae dark (Fig. 5 C), and maxillary formula (MF) as follows: 1 + 1, 5 + 5 (4 – 5), 8 (7 – 8) + 0, 3 (3 – 4) + 9 (8 – 9), 1 + 1. Maxillary carrier ~ 2.8 × shorter than MI, rectangular anteriorly, triangular posteriorly. MI forceps-like, without attachment lamellae, falcal arch extended at sub-right angle, basal outer edge arched, basal inner edge lacking a curvature. Closing system ~ 4.2 × shorter than MI. Ligament between MI and MII dark. MII without attachment lamella, teeth triangular, distributed on <1 / 2 of plate length. Ligament between MII and MIII dark. MIII single, longer than left MIV, slightly curved, with equal-sized triangular teeth, without attachment lamella. Left MIV short (<1 / 2 the size of right MIV), attachment lamella dark, curved. Right MIV long, with teeth triangular, decreasing in size and teeth curved posteriorly; attachment lamella curved, dark. MV paired, longer than high. Mandible dark, longer than MI; cutting plates whitish (Fig. 5 D). First and second parapodia located ventrolaterally but gradually positioned dorsolaterally on subsequent segments. Chaetal lobes conical and directed to ventral cirri in anterior chaetigers, conical in median and posterior chaetigers (Fig. 5 E – G). Prechaetal lobe shorter than chaetal lobe throughout body. Postchaetal lobe rounded and longer than chaetal lobe in anterior chaetigers, conical in mid-body onwards and absent in the posterior-most chaetigers. Dorsal cirri digitiform with slender and tapering tips longer than ventral cirri anteriorly, digitiform and slightly longer from mid-body, digitiform and approximately similar length in posterior-most chaetigers (Fig. 5 E – G). Ventral cirri digitiform in first chaetigers, basally inflated with digitiform tip from chaetiger 15 onwards (Fig. 5 E – G). Branchiae pectinate, from chaetiger 41 (27 – 58), branchial filaments 3 × longer than dorsal cirri where best developed; number of filaments increasing from five anteriorly to nine in mid-body, decreasing to three in last several chaetigers. Black dot present at the base of dorsal cirri from median chaetigers toward posterior chaetigers (Fig. 5 F – H). Notoaciculae absent, neuroaciculae black, blunt, and translucent at distal end along most of body, pale brown in posterior-most parapodia; three or four per parapodium in anterior, one or two per parapodium in median and posterior chaetigers (Fig. 5 E – G). Supra-acicular chaetae with limbate capillaries and pectinates, subacicular chaetae with limbate capillaries, compound chaetae absent (Fig. 6 A, B). Three types of pectinate chaetae were identified (types 1, 2, 4; see Fig. 2): type 1: thin, narrow isodont with 28 short and slender inner teeth, outer teeth longer on one side, present only in the anterior body region (Fig. 6 C); type 2: thin, wide isodont with ~ 30 – 32 short and slender teeth, present only in median and posterior region (Fig. 6 C, D); type 4: thick, wide isodont with ~ 23 short and slender inner teeth, present only in posterior region (Fig. 6 E, F). Anodont pectinate chaetae and subacicular hooks (n = 30) completely absent. Pygidium with crenulated margin, with two pairs of pygidial cirri attached (Fig. 5 I).	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
BF9FE410DC1E56E49E0865806C6310C6.taxon	etymology	Etymology. The new name denotes the type locality (Kerteh River) where the specimens were collected.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
BF9FE410DC1E56E49E0865806C6310C6.taxon	distribution	Distribution. Known only from the type locality.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
37BB3E0577F650AD9CA20FA6E8FDE9F4.taxon	description	Figs 1, 2, 8, 9, 10	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
37BB3E0577F650AD9CA20FA6E8FDE9F4.taxon	diagnosis	Diagnosis. Prostomium completely bilobed, five prostomial appendages without articulations; eyes present. Peristomium without peristomial cirri. Maxillary apparatus with four pairs of maxillae, an unpaired on the left side, MI with falcal arch extended at sub-right angle, basal outer edge arched, basal inner edge lacking curvature. MII with triangular teeth and without attachment lamella. MIII slightly curved, with equal-sized triangular teeth, without attachment lamella. MIV with rectangular and curved attachment lamella. Branchiae distributed along entire body. Dorsal cirri without articulations; postchaetal lobe well developed in anterior regions. Ventral cirri with swollen, inflated base. Sub-aciculae black, blunt, and translucent at distal end, pale brown in posterior-most parapodia. Supra-acicular chaetae include limbate, pectinate thin, narrow isodont with short and slender inner teeth, pectinate thick, wide isodont with short or long and slender inner teeth, and pectinate thick, narrow and wide anodont with long and thick inner teeth. Subacicular chaetae include only compound spinigers. Subacicular hook unidentate throughout chaetigers. Pygidium with two pairs of anal cirri, without articulation.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
37BB3E0577F650AD9CA20FA6E8FDE9F4.taxon	description	Description (based on holotype, with variation in parentheses for paratypes). Preserved specimen beige (Fig. 8 A), 257 (165 – 294) chaetigers, 94 mm (37 – 144 mm) long, L 10 - 5.25 mm (3.45 – 5.85 mm), W 10 - 2.85 mm (1.95 – 3.15 mm), excluding parapodia. Anterior region of body with dorsum convex and flat ventrum, without groove (Fig. 8 A); body depressed from chaetiger 25, elongated and tapering at distal end. Live specimens pink with red branchiae (Fig. 10 D). Prostomium bilobed, anteriorly rounded with two dorsoventrally flattened lobes with an anterior notch between them (Fig. 8 A, B). Prostomial appendages in a semicircle, median antenna isolated by a gap (Fig. 8 B). Palps reach middle of second peristomial ring; lateral antennae reaching chaetiger 2; median antenna reaching chaetiger 3. Palpophores and ceratophores ring-shaped, short, and thick; palpostyles and ceratostyles tapering, and slender. Prostomial appendage peduncles absent. A pair of faded brown eyes present at posterior base of prostomium, between palps and lateral antennae (Fig. 8 B). Peristomium larger and wider than prostomium; first ring is 2.5 × longer than second ring, separation between rings distinct on all sides. Maxillae pale brown (Fig. 8 C), and maxillary formula as follows: MF = 1 + 1, 5 (4 – 5) + 5 (5 – 6), 7 (6 – 7) + 0, 4 (4 – 5) + 8 (5 – 8), 1 + 1. Maxillary carrier ~ 2.5 × shorter than MI, rectangular anteriorly, triangular posteriorly. MI forceps-like, without attachment lamellae, falcal arch extended at sub-right angle, basal outer edge arched, basal inner edge lacking a curvature. Closing system ~ 3 × shorter than MI. Ligament between MI and MII pale brown. MII without attachment lamella, teeth triangular, distributed on <1 / 2 length of the plate. Ligament between MII and MIII pale brown. MIII single, longer than left MIV slightly curved, with equal-sized triangular teeth, without attachment lamella. Left MIV short (<1 / 2 the size of right MIV) with rectangular attachment lamellae. Right MIV long with curved attachment lamellae, teeth triangular, decreasing in size and teeth curved posteriorly. MV paired. Mandible pale brown, with concentric stripes, longer than MI; cutting plates whitish (Fig. 8 D). First few parapodia located ventrolaterally but gradually becoming dorsolateral in subsequent segments. Chaetal lobes rounded in anterior and posterior chaetigers, conical in median chaetigers (Fig. 8 E – G). Prechaetal lobe shorter than chaetal lobe throughout body. Postchaetal lobe digitiform in first three chaetigers then rounded thereafter; longer than chaetal lobe in median chaetigers onwards, become shorter and absent in the posterior-most chaetigers. Dorsal cirri digitiform and slender, longer than ventral cirri anteriorly, slightly longer or similar from mid-body towards posterior-most chaetigers (Fig. 8 E – G). Ventral cirri thumb-shaped with rounded wide tips in first few chaetigers, basally inflated with digitiform tip from chaetiger 15, and gradually becoming conical posteriorly (Fig. 8 E – G). Branchiae pectinate, from chaetiger 24 (16 – 27) and continuing to last ~ 10 chaetigers, branchial filaments 4 × longer than dorsal cirri where best developed; number of filaments increasing from three anteriorly to six in mid-body, decreasing to one in last several chaetigers. Notoaciculae absent, neuroaciculae black, blunt, and translucent at distal end along most of body, pale brown in posterior-most parapodia; ~ 2 or 3 per parapodium in anterior, one per parapodium in median and posterior chaetigers (Fig. 8 E – G). Supra-acicular chaetae with limbate capillaries and pectinates. Five types of pectinate chaetae present (types 1, 4, 5, 6, 8) (see Fig. 2): type 1: thin, narrow isodont with 7 – 12 short and slender inner teeth, outer teeth longer, but with varying lengths, present in anterior and median body region (Fig. 9 A, B); type 4: thick, wide isodont with 12 – 15 short and slender inner teeth, present only in median and posterior region (Fig. 9 C); type 5: thick, wide isodont, with 15 – 18 long and slender inner teeth, only present in posterior region (Fig. 9 D); type 6: thick, narrow anodont with 11 or 12 long thick teeth, only present in posterior region (Fig. 9 E); type 8: thick, wide anodont, with five inner long and thick teeth, only present in the posterior region (Fig. 9 F). Subacicular chaetae with compound spinigers (Fig. 9 G). Subacicular hooks pale brown, translucent at distal end, emerge from chaetiger 37 (26 – 42) and then present on all chaetigers, one per parapodium; subacicular hooks unidentate throughout chaetigers (Fig. 9 H). Pygidium with crenulated margin, with two pairs of tapering pygidial cirri attached to ventral side of pygidium, dorsal pair ~ 4 × longer than ventral (Fig. 8 H).	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
37BB3E0577F650AD9CA20FA6E8FDE9F4.taxon	etymology	Etymology. The name denotes the type locality (Merchang estuary) where the specimens were collected.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
37BB3E0577F650AD9CA20FA6E8FDE9F4.taxon	distribution	Distribution. Known only from the type locality and Setiu Wetlands, Terengganu, Malaysia.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
01A9E8EEC19B5AB194C50570A564565C.taxon	description	Figs 1, 2, 11, 12, 13	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
01A9E8EEC19B5AB194C50570A564565C.taxon	diagnosis	Diagnosis. Prostomium completely bilobed, five prostomial appendages without articulations; eyes present. Peristomium without Peristomial cirri. Maxillary apparatus with four pairs of maxillae, an unpaired on the left side, MI with falcal arch extended at sub-right angle, basal outer edge arched, basal inner edge lacking curvature. MII with triangular teeth and without attachment lamella. MIII slightly curved, with equal-sized triangular teeth, without attachment lamella, MIV with curved attachment lamella. Branchiae distributed along entire body. Dorsal cirri without articulations; postchaetal lobe well developed in anterior regions. Ventral cirri with swollen, inflated base. Sub-aciculae black, blunt, and translucent at distal end, pale brown in posterior-most parapodia. Supra-acicular chaetae include limbate, pectinate thin, narrow and wide isodont with short and slender inner teeth, and pectinate thick, wide anodont with long and slender or thick inner teeth. Subacicular chaetae include only compound spinigers. Subacicular hook unidentate, and a few bidentate present in posterior chaetigers. Pygidium with two pairs of anal cirri, without articulation.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
01A9E8EEC19B5AB194C50570A564565C.taxon	description	Description (based on holotype, with variation in parentheses for paratypes). Preserved specimens beige (Fig. 11 A), ~ 154 (141 – 259) chaetigers, ~ 51 mm (27 – 75 mm) long, L 10 - 2.7 mm (2.85 – 4.8 mm), W 10 - 1.8 mm (1.65 – 2.55 mm), excluding parapodia. Anterior region of the body with dorsum convex and flat ventrum, without groove; body depressed from chaetiger 11, elongated and tapering at the distal end. Live specimens pink (Fig. 13 B, D). Prostomium bilobed, anteriorly rounded with two dorsoventrally flattened lobes separated by an anterior notch (Fig. 11 A, B). Prostomial appendages in a semicircle, median antenna isolated by a gap (Fig. 11 B). Palps reaching chaetiger 3; lateral antennae reaching chaetiger 4; median antenna reaching chaetiger 5. Palpophores and ceratophores ring-shaped, short, and thick; palpostyles and ceratostyles tapering and slender. Prostomial appendage peduncles absent. Pair of faded brown eyes at posterior base of prostomium, between palps and lateral antennae. Peristomium similar in size (width and length) to prostomium; the first ring is 1.5 × longer than second ring, and separation between rings distinct on all sides. Maxillae dark brown (Fig. 11 C) and maxillary formula as follows: MF = 1 + 1, 5 (4 – 5) + 5 (4 – 6), 5 (4 – 6) + 0, 3 (3 – 4) + 6 (7 – 8), 1 + 1. Maxillary carrier ~ 2.4 × shorter than MI, rectangular anteriorly, triangular posteriorly. MI forceps-like, without attachment lamellae, falcal arch extended at sub-right angle, basal outer edge arched, basal inner edge lacking a curvature. Closing system ~ 5 × shorter than MI. Ligament between MI and MII pale brown. MII without attachment lamella, teeth triangular, distributed along half of plate length. Ligament between MII and MIII pale brown. MIII single, longer than left MIV, slightly curved, with equal-sized triangular teeth, without attachment lamella. Left MIV short (<1 / 2 the size of right MIV) with curved attachment lamellae. Right MIV long, with teeth triangular with curved attachment lamellae, decreasing in size and teeth curved posteriorly. MV paired. Mandibles dark brown (Fig. 11 D), with concentric stripes; longer than MI; cutting plates whitish. First parapodia occur ventrolaterally, gradually becoming dorsolateral in following segments. Chaetal lobes rounded in all chaetigers (Fig. 11 G – I). Prechaetal lobe shorter than chaetal lobe along whole body. Postchaetal lobe digitiform in first three chaetigers and rounded thereafter; conical and longer than chaetal lobe in median and posterior chaetigers, becoming shorter and absent in the posterior-most chaetigers. Dorsal cirri thumb-shaped with digitiform tips, shorter than ventral cirri in anterior, digitiform with slender and tapering tips; slightly longer or similar length from mid-body onwards and shorter in posterior-most chaetigers (Fig. 11 G – I). Ventral cirri thumb-shaped with digitiform tips in the first few chaetigers, basally inflated with digitiform tip from chaetiger 15 onwards, and gradually becoming conical posteriorly (Fig. 11 G – I). Branchiae pectinate, from chaetiger 20 (15 – 25) and continuing to near the end (~ 8 last chaetigers without branchiae), branchial filament 4 × longer than dorsal cirri where best developed; number of filaments increasing from two anteriorly to five in mid-body, decreasing to one in last several chaetigers. Notoaciculae absent, neuroaciculae black, blunt, and translucent at distal end on most of body, pale brown in posterior-most parapodia; ~ 2 or 3 per parapodium in anterior, one per parapodium in median and posterior chaetigers (Fig. 11 G – I). Supra-acicular chaetae with limbate capillaries and pectinates. Four types of pectinate chaetae were identified (types 1, 2, 7, 8) (see Fig. 2): type 1: thin, narrow isodont with ~ 18 – 22 short and slender inner teeth, outer teeth longer, but of varying lengths, present in anterior and median body region (Fig. 12 A, B); type 2: thin, wide isodont with 14 – 21 short and slender teeth, outer teeth same length as inner teeth, present only in anterior and posterior region (Fig. 12 C, D); type 7: thick, wide anodont with 15 – 18 long and slender inner teeth, only present in posterior region (Fig. 12 E, F); type 8: thick, wide anodont, with seven inner long and thick teeth, only present in posterior region (Fig. 12 F). Subacicular chaetae with compound spinigers (Fig. 12 G). Subacicular hooks unidentate (Figs 11 E, 12 H), pale brown, translucent at distal end, commencing from chaetiger 25 (21 – 38) and then present on all subsequent chaetigers, one per parapodium and with a few bidentate hooks in posterior chaetigers (Fig. 11 F). Pygidium with crenulated margin, with two pairs of tapering pygidial cirri attached to ventral side of pygidium, dorsal pair ~ 4 × longer than ventral one (Fig. 11 J).	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
01A9E8EEC19B5AB194C50570A564565C.taxon	etymology	Etymology. The name refers to the type locality Setiu Wetlands.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
01A9E8EEC19B5AB194C50570A564565C.taxon	distribution	Distribution. Known only from the type locality.	en	Che Engku Abdullah, Che Engku Siti Mariam, Idris, Izwandy, Fahmi, Afiq Durrani Mohd, Flaxman, Beth, Hutchings, Pat (2024): Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia. ZooKeys 1204: 65-103, DOI: 10.3897/zookeys.1204.117261
