taxonID	type	description	language	source
038A9201E41AFFCBFF7E8F95728F510B.taxon	description	urn: lsid: zoobank. org: act: ACBF 2731 - 315 F- 4 BED-B 31 C- 17 EE 83 CD 310 C	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E41AFFCBFF7E8F95728F510B.taxon	materials_examined	Material examined. Holotype (NSMT-Pol H- 975) and two paratypes (NSMT-Pol P- 976): Japan, Misaki: Arahaima Beach, Sagami Bay, Misaki, 35 ° 09 ' 34 " N 139 ° 36 ' 40 " E, 2 – 5 m, coll. Oguchi, 2022. Three paratypes (ZMUG 32498) and additional material (NSMT-Pol 113615): Japan, Misaki: Sagami Bay, Misaki Marine Biological Station, 35 ° 09 ' 36.1 " N 139 ° 36 ' 40.1 " E, 2 – 5 m, coll. Aguado & Oguchi 2019, Sato & Aguado 2024. Additional material (ZMUG 32500): Japan, Sugashima Island: Kamekobana, 34 ° 28 ' 40 " N 136 ° 53 ' 00 " E, 5 m, coll. Jimi, Tsuyuki & Ishibashi 2024. Comparative material. Virchowia pectinans (Hartmann-Schröder, 1983) (AM-W 41620): New South Wales: S. of Grasshopper Is., 2004.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E41AFFCBFF7E8F95728F510B.taxon	description	Description. Length between 8.7 – 12.8 mm for 37 – 39 segments, width 0.35 – 4 mm. Adult specimens with developing stolons. Body consists of prostomium, 13 segments, stolon head, 37 – 39 stolon segments (depending on the stolon’s developmental stage) and pygidium. Adult specimens without stolon consist of prostomium, 50 segments and pygidium. Body slender, tubular, ventrally flattened and thickest in segments 5 – 7 (Fig. 4 A). Body and appendages contracted in fixed material (Fig. 4 A), longer and slender in live specimens (Fig. 5 A, B). Prostomium with four red eyes in trapezoidal arrangement. Nuchal epaulettes sand coloured in both live and fixed specimens, originating dorsally on prostomium (Figs 4 A, 5 B), bifurcated (Fig. 6 A – C, E), and highly ciliated (7 C). One band of cilia around the eyes (Fig. 7 D). Median antenna thick (Fig. 4 A), sand coloured, as long as three segments (Fig. 5 A – B). Lateral antennae slim, sand coloured, length 2 / 3 of median antenna (Figs 4 A, 5 A – B). Palps ventrally located, basally fused to the prostomium, free distal ends (Fig. 6 D). Peristomium fused with prostomium, not distinguishable. Dorsal tentacular cirri 2 / 3 length of median antenna, ventral pair long, thinner than dorsal pair (Figs 4 A, 5 A – B). Median antenna, lateral antennae, tentacular cirri cylindrical, distally pointed (Figs 4 A, 5 A – B, 6 A – B, E). First dorsal cirri reaching chaetiger 3, longer than lateral antennae, fourth dorsal cirri as long as first pair (Figs. 4 A, 5 A – B). Second and third dorsal cirri smaller, as long as ventral tentacular cirri (Figs 4 A, 5 A – B). Ventral cirri fused to parapodia (Figs 4 A, 7 A). Dorsal cirri follow consistent pattern of alternation (pointing up: U; down: D): adult head, U, D, D, U, D, U, D, D, U, D, U, D, U, stolon head, D, U, D, U, D, U, D, D, D, U, D, U, D, U, D, D, U, U, D, D, D, U, D, D, U, U, D, D, D, U, D, D, U, D, D, U, D, stolon pygidium (Fig. 5 A – B). Same alternation pattern in all specimens. No alternation in cirri placement (Fig. 8 A). Upwards oriented dorsal cirri clavate, thick, sandy colouration, distally pointed (Figs 4 A, 5 A – B). Downwards oriented dorsal cirri short, slim, whitish, distally pointed (Figs 4 A, 5 A – B). Segments faintly secondarily annulated, more pronounced in anterior region (Figs 4 A, 6 A, 8 B). All dorsal surface, dorsal cirri and antennae with glandular openings (Figs 8 B, 9 D, E). Bunch of cilia in antennae and first dorsal cirri (Figs 7 A, B, 9 A – D) and “ star-shaped ” filament extensions (Fig. 9 B, F). Striking colour pattern (Figs 5, 6), consistent in all specimens, only slight deviations in the stolons. Colouration identical in both live and fixed specimens with no fading observed after five years of storage. Segment colours vary between sandy / beige and dark brown. Thin, dark brown bands mark the end / the beginning of each segment (Fig. 5 A, B). Two dark-brown, rounded spots located laterally between segments 3 / 4; 8 / 9 and 12 / 13 of the adult holotype. Spots can vary in size; but placement is consistent in all specimens. Most segments with at least one line of small white refringent dots spanning across the width of the segment, some segments with up to four lines of white dots. Dotted lines may continue onto the downwards oriented dorsal cirri, but never onto the upwards oriented dorsal cirri. Most segments do not vary in colour within themselves, but the number of white dots per annulation may vary within a segment. Segments 10 and 11 of the adult holotype appear almost white and shining due to high number of white dots. Segments 4, 9 and 13 of the adult holotype appear dark brown. Parapodia with 7 – 10 chaetae (Fig. 10 A). Parapodia rounded, bilobed (Fig. 10 A). Chaetae bidentate, without blade serration (Figs 4 B – C, 10 B – D), and simple (shafts and blades fused, Figs 10 B, C), 1 – 2 most-ventral ones within the chaetae fascicle remain compound (Fig. 10 D). Proximal tooth larger than distal one (Figs 4 C, 10 C, D). Chaetae from anterior and posterior-most segments with elongated distal teeth, especially the proximal one. No simple chaetae or bayonet chaetae present. Two pointed aciculae. Long and twice-sinuated pharynx reaching segments 1 – 3. Trepan provided with 25 unequal teeth, alternating 1 large and 1 – 2 small teeth, arranged in 1 ring (Fig. 4 D). Proventricle cylindrical, occupying segments 3 – 6 (not clearly seen by transparency) in both live and fixed specimens. Pygidium with two small, opaque and cylindrical anal cirri (Fig. 5 A – B, 6 F).	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E41AFFCBFF7E8F95728F510B.taxon	biology_ecology	Reproduction. Schizogamy by anterior scissiparity. Developing stolon behind segment 13 (Fig. 5 A – B). Stolon with four red eyes in trapezoidal arrangement, anterior pair larger (Fig. 5 B). Median and lateral antennae developed, small, white opaque. Cirri, at this point of development (Figs 5 A, B, 8 C – D), with same colour and shape as anterior adult cirri. Pattern of alternation consistent across all stolon specimens. Pygidium with pair of small, rounded, white opaque anal cirri. Segment colours vary between sandy / beige and dark brown. Colouration pattern as described for the atoke specimens. Two dark-brown, rounded spots located laterally between segments 4 / 5; 8 / 9; 9 / 10; 10 / 11; 14 / 15; 15 / 16; 22 / 23; 30 / 31 of the stolon. Segments 6, 7, 13, 17, 18, 24 – 26, 29, 30 and 33 – 36 of the stolon appear almost white and shining due to high number of white dots. Segments 5, 8 – 11, 15, 16, 20, 24, 28 and 32 dark brown. Parapodia with 7 – 10 chaetae. Chaetae with slim shafts, no blade serration. Bayonet chaetae not seen. No notochaetae present at the described development stage. Habitat. Rocky shorelines, shallow waters 2 – 5 m deep, on algae and below rocks.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E41AFFCBFF7E8F95728F510B.taxon	discussion	Remarks. Virchowia christophi sp. nov. is characterized by the unique combination of bifurcated nuchal epaulettes, a striking colour pattern, the distinctly shaped chaetae (with long distal teeth and absence of serration on verge), and the alternation pattern of dorsal cirri in colour, shape and size. Its diagnostic characters fit well with those from the genus Virchowia (Nygren, 2004) (Table 1). The palps in Virchowia christophi sp. nov. are not completely fused to the prostomium. Virchowia branchiata Averincev, 1972, from the Antarctic, is the only other Autolytinae with nuchal epaulettes as bifurcated outgrowths (Nygren 2004). However, this species has chaetae with fine spinulation on verge, bayonet chaetae and less teeth on the trepan ring. Virchowia pectinans from Australia has a complex colour pattern, whose colours are similar to those of V. christophi sp. nov. (pers. obs. from AM fixed material). However, the colour pattern is different and it has chaetae with more curved distal teeth and long spinulation on verge. The number of trepan teeth and convolutions of the pharynx are also different to those of V. christophi sp. nov. In Japan, the only known species of the genus is V. japonica Imajima & Hartman, 1964, which was described from a single male stolon (Nygren 2004). This species possesses compound chaetae with serrations on the verge and includes bayonet chaetae. In contrast, V. christophi sp. nov. mostly has simple chaetae with shafts and fangs fully fused, (excepting those located most ventrally in the chaetiger), long distal teeth, serrations on the verge completely missing, and absence of bayonet chaetae. Additionally, V. japonica exhibits only DU-groups of alternating cirri, while the dorsal cirri alternation pattern in V. christophi sp. nov. is different. Regarding the shape of compound chaetae, V. spirifer Augener, 1913 is the only other species of Virchowia without serrations or spines along the cutting margin of the chaetae. Similarly, Imajimaea draculai also lacks blade serration along the blades of compound chaetae. However, V. christophi sp. nov. can be distinguished from V. spirifer and I. draculai, in addition to the bifurcated nuchal epaulettes, by its chaetae shape, trepan structure, absence of bayonet chaetae, and distinct dorsal cirri pattern. SEM images revealed glandular structures covering the entire body of V. christophi sp. nov. While similar structures have been observed in other syllids (San Martín & Aguado 2012; Jimi et al. 2024), their function remains unclear.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E41AFFCBFF7E8F95728F510B.taxon	distribution	Distribution. Misaki Sagami, Bay; Sugashima Island; Japan; NW Pacific.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E41AFFCBFF7E8F95728F510B.taxon	etymology	Etymology. This species is dedicated to Professor Dr. Christoph Bleidorn, for all his important contributions to systematics, and specifically to the phylogenetic relationships of Annelida.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E412FFD6FF7E8EB4725D5193.taxon	description	urn: lsid: zoobank. org: act: EBEFAB 46 - 9863 - 4144 - 9117 - 7013 B 664845 B	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E412FFD6FF7E8EB4725D5193.taxon	materials_examined	Material examined. Holotype (NSMT-Pol H- 977) and seven paratypes (NSMT-Pol P- 978): Japan, Misaki: Arahaima Beach, Sagami Bay, Misaki, 35 ° 09 ' 34 " N 139 ° 36 ' 40 " E, 2 – 5 m, coll. Sato, 2022. Paratypes (NSMT-Pol P- 1006, ZMUG 32499) and additional material. (NSMT-Pol 113616): Japan, Misaki: Araihama Beach, Sagami Bay, Misaki Marine Biological Station, 35 ° 09 ' 36.1 " N 139 ° 36 ' 40.1 " E, 2 – 5 m, coll. Oguchi & Aguado 2019, Sato & Aguado 2024.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E412FFD6FF7E8EB4725D5193.taxon	description	Description. Large-sized body, largest specimen examined (holotype) 19.5 mm long, 0.8 mm wide, prostomium, 94 body segments and pygidium. Paratypes vary significantly in number of segments and body length. Body length ranges between 7.75 – 19.5 mm, number of segments between 58 – 94. Body cylindrical, broad (Figs 11 A, 12 A – B), flattened ventrally (Fig. 13 A, D). Main body colour red, anterior end reddish / pink, midbody section dark red, posterior region light red to white / opaque (Figs 12 – 14) (in live and fixed specimens). Appendages in anterior region faintly orange / red coloured (Fig. 12 B), in midbody and posterior section white / opaque (Fig. 12 A – B). Segments secondarily triannulated (Figs 11 A, 12 A, 13 D, E). Segments thickest in anterior region, segments 1 – 8 enlarged (Figs 12 A – B, 13 A, 15 A). Body surface, including cirri, covered by small papillae (Figs 15 C – E, 16 G). Prostomium with 4 lensed eyes arranged in trapezoidal shape, one thick and short median antenna and two lateral antennae (Figs 11 A, 12 A, 13 A, D). Ciliation around the eyes present (Fig. 15 C). Median antenna similar to prostomium length, lateral antennae longer than prostomium (Figs 13 D, 15 A, B). Palps broad, elongated, rounded, reddish in colour, basally fused (Fig. 13 B, C). Peristomium with elongated, forward-pointing, cylindrical dorsal and ventral tentacular cirri (Figs 13 D, 15 A – B). Dorsal one longer than ventral one (Fig. 13 D). Nuchal organs in ciliated grooves (Fig. 15 B, E). Dorsal cirri digitiform (Fig. 12 A, B), in a consistent pattern in their arrangement and length (Figs 12 A, B, 13 E). The dorsal cirri pointing upwards (U) arranged on a high position (closer to the dorsum) are double the length and thickness than those downwards (D) directed, whose arrangement is closer to the ventral side (Fig. 12 A). The pattern of the first nine dorsal cirri is: U, D, D, U, D, U, D, D, U. Following ones alternate in a D, U, D, U, D, U pattern until they shift to the same position and continue at same arrangement height along the rest of the body. The shift from alternating to non-alternating dorsal cirri is consistent across all specimens, but the segment at which the alternation stops varies between individuals and ranges from segment 32 – 37. In some specimens, fourth dorsal cirri thickened compared to rest of upwards oriented dorsal cirri (Figs 11 A, 15 A). Ventral cirri of same length as parapodia, ovate, covered in small papillae (Figs 16 A – E, 17 A, C). Parapodia short, thick, distally bilobed, each with 12 compound chaetae (Fig. 17 A – C). Compound chaetae bidentate with small serrations along the inner margin of the blade (5 μm) (Figs. 11 B, 17 C, D). Shafts smooth and slender. Longest chaetae article ~ 43 µm, shortest ~ 18 µm. Simple chaetae not seen. Pygidium short and triangular, with two club-shaped and short anal cirri (Fig. 14 A, 16 F). Pharynx straight, occupying segments 1 – 6, followed by a cylindrical proventricle present in segments 7 – 11 in both live and fixed specimens (Fig. 12 B). One single pharyngeal tooth located retarded on posterior dorsal outer side of the pharynx.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E412FFD6FF7E8EB4725D5193.taxon	biology_ecology	Reproduction. Schizogamy by scissiparity. Paratypes adult specimens developing mature dicerous female stolons (Fig. 14 B – H). The stolon head with two pairs of red eyes (Fig. 14 E – F, H). Lateral antennae opaque, smaller than cirri, observed in developing and mature stolons (Fig. 14 H). Female stolons with ovules visible by transparency, red / purple in colour (Fig. 14 B – D, H). Dorsal cirri and ventral cirri present, elongated. Parapodia and compound chaetae present, notoaciculae present in mature stolons (Fig. 14 H). Pygidium with two club-shaped anal cirri, similar to adult specimens (Fig. 14 B, D). Stock forming a secondary tail ventrally while the stolon is still attached to the parental stock observed in paratype (Fig. 14 F). Regenerating posterior end after detachment of stolon (Fig. 14 G). Habitat. Rocky shorelines, shallow waters 2 – 5 m deep, on algae and coral rubble.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E412FFD6FF7E8EB4725D5193.taxon	discussion	Remarks. Paraopisthosyllis rufa sp. nov. is characterized by the distinctive alternation pattern of dorsal cirri and the distinct shape of the compound chaetae, together with its prominent colour in both live and fixed specimens (5 years storage). It is the first record of the genus Paraopisthosyllis in Japan (Jimi 2024). Chaetae of P. rufa sp. nov. are most similar to those of P. correiae Paresque et al. 2016, P. fusigera Augener, 1913, P. ornaticirra San Martín & Hutchings, 2006 and P. phyllocirra Hartmann-Schröder, 1991. They all have bidentate compound chaetae with serrations along the blade and spinulations on the chaetae shafts. Additionally, P. brevicirra Hartmann-Schröder, 1979, P. fusigera and P. phyllocirra all lack simple chaetae as P. rufa. sp. nov. Like in most Paraopisthosyllis species (except for P. fusigera and P. victoriae San Martín, López & Aguado, 2009) the body surface of P. rufa sp. nov. is covered with small papillae. P. rufa sp. nov. is further differentiated from P. victoriae by the continuous prominence of the intersegmental furrows and from P. fusigera by a longer pharynx and proventricle, as well as the red colouration. The regeneration of the pygidium, while the stolon is still attached, firstly reported herein for Paraopisthosyllis, is a feature in common with Megasyllis and Alcyonosyllis (Aguado & Glasby 2015; Nakamura et al. 2023; Sato et al. 2024). The three genera form a monophyletic group, potentially inheriting this ability from their common ancestor. Convergently, other genera within Syllinae regenerate the pygidium while the stolons are still attached, such as Ramisyllis kingghidorahi Aguado et al. 2022, R. multicaudata Glasby, Schroeder & Aguado, 2012, Parahaplosyllis kumpol and some species of Trypanobia Imajima & Hartmann, 1964, Trypanosyllis and Myrianida (Okada 1937; Glasby et al. 2012; Álvarez-Campos et al. 2013; Aguado et al. 2022). However, a detailed morphological comparison of this process in different groups has never been performed.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E412FFD6FF7E8EB4725D5193.taxon	distribution	Distribution. Misaki, Sagami Bay; Japan; NW Pacific.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E412FFD6FF7E8EB4725D5193.taxon	etymology	Etymology. This species is the first known species of Paraopisthosyllis with a striking red colouration and is therefore named “ rufa ” from Latin “ rufus “ meaning red.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E40AFFDEFF7E8B6375B755C3.taxon	materials_examined	Material examined. Two specimens (NSMT-Pol 113617), Japan, Misaki: Araihama Beach, Sagami Bay, Misaki Marine Biological Station, 35 ° 09 ' 36.1 " N 139 ° 36 ' 40.1 " E, 2 – 5 m, coll. Oguchi & Aguado, 2019. Additional material (ZMUG 32501): Japan, Misaki: Sagami Bay, Misaki Marine Biological Station, 35 ° 09 ' 36.1 " N 139 ° 36 ' 40.1 " E, 2 – 5 m, coll. Aguado & Sato 2024.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E40AFFDEFF7E8B6375B755C3.taxon	description	Description. Largest specimen complete, 11.8 mm long and 0.5 mm wide without chaetae. 82 chaetigers, prostomium and pygidium. Body subcylindrical, broad, ventrally flattened (Fig. 18). Segments 1 – 2 dark brown, segments 3 – 6 white, segments 7 – 9 dark brown, rest is dark red, segments ventrally white (Fig. 18 A – E). Dorsal side with four rows of white spots, two spots per row and segment, rows located more ventrally fade out posteriorly (Fig. 18 A – E). Head appendages (except palps), pygidium and cirri white (Fig. 18 A, D – E). Prostomium with one median antenna located at the posterior end, two pairs of orange / red eyes and a pair of lateral antennae (Figs 18 A, D – E, 19 B). Two brown palpi form the anterior part of the prostomium (Fig. 18 A, D – E). Grooves of cilia around the eyes, nuchal organs located at the posterior end of the prostomium, between prostomium and first segment (Fig. 20 B, E). Two pairs of tentacular cirri (Fig. 20 B). Dorsal cirri longer in anterior region, become gradually shorter towards posterior end (Fig. 18 A – E). Annulated dorsal cirri (Figs 19 B, F, 20 A – D, F) with around 9 annulations. Pygidium with two short, white anal cirri (Fig. 20 C, F). Anterior chaetae compound, 10 – 14 per parapodium (Fig. 21 B – G). Anterior chaetae with long and slender shafts, denticles at the distal end of the shaft, large blades with serrations along the cutting margin and two distal teeth, proximal one slightly larger than distal one (Fig. 21 C – D). Posterior parapodia with eight compound chaetae with short and broad shafts, bidentate (Fig. 21 E – G). Additionally, posterior parapodia with two short and broad simple chaetae, one dorsal with a subdistal secondary tooth and one unidentate, distally curved ventral (Fig. 21 A, E – G). Last chaetiger with only eight chaetae (six compound, two simple).	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E40AFFDEFF7E8B6375B755C3.taxon	biology_ecology	Reproduction. Schizogamy by scissiparity. Adult specimens developing each a dicerous stolon (Fig. 19 A – E). Stolon with 14 – 21 body segments and pygidium. Stolon with two pairs of orange / red eyes, located laterally, one pair more dorsally, one more ventrally (Fig. 19 A – E). Two lateral antennae developed, small (Fig. 19 C, E). Female stolons with green ovules visible by transparency (Fig. 19 E). Male stolons with beige sperm visible by transparency (Fig. 19 B). Pygidium with pair of small and conical anal cirri. Compound chaetae present. Notoaciculae present in developing and mature stolons (Fig. 19 A – E). Stock forming a pair of tail primordia ventrally while the stolon is still attached to the parental stock (Fig. 19 D). The tail primordia (Fig. 19 F) fuse to form a new pygidium after the detachment of stolon. Habitat. Rocky shorelines, shallow waters 2 – 5 m deep, on algae and coral rubble.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E40AFFDEFF7E8B6375B755C3.taxon	discussion	Remarks. Syllis okadai is distinguished by a unique colour pattern (live and preserved specimens) and specially shaped compound chaetae in both the anterior and posterior regions. Additionally, the ciliated grooves around the eyes, a newly identified feature, were not mentioned in the original description. Apart from the newly identified features, the examined specimens closely match the original description.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
038A9201E40AFFDEFF7E8B6375B755C3.taxon	distribution	Distribution. Cambodia, Andaman Islands; Gulf of Siam; Seto, Manazuru and Misaki, Japan.	en	Springer, Chris, Sato, Daisuke S., Oguchi, Kohei, Jimi, Naoto, Miura, Toru, Aguado, M. Teresa (2025): Two new species of Syllidae (Annelida) from Misaki Bay and Sugashima Island, Japan. Zootaxa 5632 (1): 51-83, DOI: 10.11646/zootaxa.5632.1.3, URL: https://doi.org/10.11646/zootaxa.5632.1.3
