taxonID	type	description	language	source
03D387B6FFBBFFC5C9837B374A8810E7.taxon	type_taxon	Ty p e s p e c i e s. Chiton janeirensis Gray, 1828, sensu Thiele, 1893 (= Chiton affinis Issel, 1869), by subsequent designation.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC6C9837EDA4B0F1217.taxon	description	Ty p e s p e c i e s. Chiton confissus Gould, 1846 (= Chiton lamellosus Quoy et Gaimard, 1835) by subsequent designation by Pilsbry, 1893.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC6C9B97DCA4BE515D1.taxon	description	Figs. 1, 2, 12 B	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC6C9B97DCA4BE515D1.taxon	description	Ty p e l o c a l i t y. Queensland, Keppel Bay, Emu Park. M a t e r i a l e x a m i n e d. Papua New Guinea, Bismarck Archipelago, Manus Island, Silver Sound, 02 ° 01 ′ S, 146 ° 53 ′ E, R / V Dmitriy Mendeleev, 18 cruise, sample 4, 1 m, 1 spm, BL 14 mm (ZISP 2302), 27.01.1977. D i s t r i b u t i o n. This species is widely distributed in the western Pacific and was found in north-eastern Queensland, Papua New Guinea, Vietnam and Guangxi Province of southern China. It is first find of the species near Papua New Guinea. The species lives near Vietnam and southern China at depth from 0 to 20 m. R e m a r k s. The studied specimen was damaged. All its features (shell, armature of girdle and head of major lateral teeth of radula match the original description and the drawings of Hull [1923]. Slit formula of this specimen is 8 / 1 / 15.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC3C9AD79BA496C13CD.taxon	description	Figs. 3 – 5, 12 C urn: lsid: zoobank. org: act: 9 A 18 C 9 A 0 - 1 FCB- 4 BA 3 - 9754 - 0549511 DA 62 E	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC3C9AD79BA496C13CD.taxon	materials_examined	Ty p e m a t e r i a l. Holotype (ZISP 2303), now disarticulated, consisting of the mount of part of girdle and radula, vial with valves, part of radula and part of girdle. Ty p e l o c a l i t y. Papua New Guinea, Astrolabe Bay, Bilibili Island, intertidal, rocks, R / V Kallisto, cruise 1, 03.01.1975, leg. B. I. Sirenko.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC3C9AD79BA496C13CD.taxon	etymology	E t y m o l o g y. From the Latin insuetus, uncommon, referring to the uncommon number of slits and rudiment of callus in the tail valve.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC3C9AD79BA496C13CD.taxon	distribution	D i s t r i b u t i o n. Known only from the type locality.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC3C9AD79BA496C13CD.taxon	diagnosis	D i a g n o s i s. Animal of medium size, shell rather low, back rounded. Tegmentum smooth in all areas except for a few weak concentric growth lines. Slit formula 9 / 1 / 2 + rudiment of callus. Girdle looking smooth, leathery, dorsal scales very small and short with one longitudinal rib, ventral scales subquadrangular, ornamented around with 14 – 15 distally converging riblets. Major lateral tooth of radula with tetracuspid cap, the outer three denticles blunt and much rounded, the innermost sharpest.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC3C9AD79BA496C13CD.taxon	description	D e s c r i p t i o n. Chiton of medium size, holotype, BL 20.0 mm, elongate oval. Shell low (dorsal elevation 0.27), back rounded, intermediate valves side slopes straight, valves slightly beaked. Tegmentum mainly yellowish with brown and olive spots. Girdle of fixed holotype colored in predominant tegmental color yellow. Head valve semicircular. Intermediate valves with anterior margin straight in a wide central part, splayed laterally, side margins rounded, hind margin almost straight at both sides of rounded apex, lateral areas not raised. Tail valve slightly narrower than head valve, the length somewhat less than half the width, front margin weakly convex in the middle, hind margin evenly convex, mucro posterior, hind slope steep, convex, antemucronal area convex. Tegmentum smooth in all areas, with a few weak concentric growth lines. Head valve with minute, black ocelli sparsely distributed in 8 radiating series in between, lateral and postmucronal areas with one row of ocelli in anterior portion. Articulamentum white with light brown in middle portion, apophyses triangular with rounded top in intermediate valves, and trapezoidal in tail valve, jugal sinus straight, about 1 / 3 of the valve’s width, provided with a very short, finely denticulated plate. Slit formula 9 / 1 / 2 + rudiment of callus, pectination and slit rays well indicated in head and intermediate valves, insertion teeth short, finely grooved on the upper side, sharply pectinated at outer edge, eaves short, solid. Tail valve with pectination on the hind parts of the apophyses, with two obsolete slits and a smooth rudiment of callus between the slits (Fig. 4 B). Girdle about 3.3 mm wide near valve V, looking smooth, leathery dorsally covered with not numerous, small scales (20 x 10 μm), protruded from cuticula, and ornamented with one longitudinal rib, and more rare small spicules (8 x 4 μm). Ventral scales (27 – 29 x 25 µm) subquadrangular, ornamented around with 14 – 15 distally converging riblets. Radula of the holotype 6.5 mm long, with 42 transverse rows of mature teeth, central tooth of radula knobby in the lower part, slightly narrow in the central part, distally widening to an even wider quadrangular blade, major lateral tooth with tetracuspid cap, the outer three denticles blunt and much rounded, the innermost sharpest. The holotype with 39 gills on both sides, extending from valve II to first half of valve VIII.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB8FFC3C9AD79BA496C13CD.taxon	discussion	R e m a r k s. The rudiment of callus bring this species closer to species of the genus Onithochiton but pectination and two obsolete slits on the sides of insertion plate of the tail valve require to place this species in the genus Lucilina. L. insueta sp. n. is superficially similar to south Australian L. dupuisi (Leloup, 1973) that has also practically smooth tegmentum, but differs from the latter in having unique rudiment of callus and only two slits in insertion plate of the tail valve (vs. 9 equidistant slits in L. dupuisi).	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFBDFFCFC9B878E14B8615A5.taxon	description	Figs. 6 – 8 urn: lsid: zoobank. org: act: 04 BE 4 B 58 - AFE 5 - 4 F 27 - B 020 - 5 B 570 A 1 B 25 F 8	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFBDFFCFC9B878E14B8615A5.taxon	materials_examined	Ty p e m a t e r i a l. Holotype (ZISP 2304) now disarticulated, consisting of mount of part of girdle and radula, vial with valves, part of radula and part of girdle. Ty p e l o c a l i t y. Papua New Guinea, Bismarck Archipelago, Manus Island, Silver Sound, 02 ° 01 ′ S, 146 ° 53 ′ E, 1 m (R / V Dmitriy Mendeleev, 18 cruise, sample 4, 27.01.1977).	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFBDFFCFC9B878E14B8615A5.taxon	etymology	E t y m o l o g y. Named in honour of my wife Alena Nemirko who help me to live and to work.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFBDFFCFC9B878E14B8615A5.taxon	distribution	D i s t r i b u t i o n. Only known from the type locality.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFBDFFCFC9B878E14B8615A5.taxon	diagnosis	D i a g n o s i s. Animal of small size, shell rounded. Intermediate valves sinuate in anterior margin, concave in the jugal area, convex at side margins, evenly convex, not beaked in posterior margin. Tail valve slightly narrower than head valve. Tegmentum of head valve, lateral area of intermediate valves, and postmucronal area of tail valve smooth, only with growth line. Pleural areas with 8 – 9 very short and deep longitudinal, sometimes interrupted grooves along diagonal line. Insertion plates very short and smooth. Dorsal spicules small, blunt-topped, with 8 – 10 ribs around. Ventral scales more or less rectangular, ornamented around 8 – 10 distally converging riblets. Major lateral tooth bearing a cusp with 4 denticles.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFBDFFCFC9B878E14B8615A5.taxon	description	D e s c r i p t i o n. Holotype of small size, BL 7.0 mm, elongate oval. Valves low (dorsal elevation 0.37), back rounded, side slopes convex, not beaked. Tegmentum light yellow with white spots. Head valve semicircular, front slope convex, posterior margin widely V-shaped, shallowly notched in the middle. Intermediate valves more than twice as wide as long, anterior margin sinuate, concave in the jugal area, convex at the pleurae, posterior margin evenly convex not beaked, lateral areas slightly raised. Tail valve slightly narrower than head valve, anterior margin slightly concave, hind margin evenly convex, mucro posterior, hind slope almost steep, convex, antemucronal slope straight. Tegmentum of head valve, lateral area of intermediate valves, and postmucronal area of tail valve smooth, only with well noticeable growth line. Pleural areas with 8 – 9 very short and deep longitudinal, sometimes interrupted grooves along diagonal line on each side. Articulamentum white, apophyses triangular with rounded top in intermediate valves, and trapezoidal in tail valve, separated by a wide, deep, slightly concave, delicately dentate sinus (10 – 11 denticles in valves IV – VI). Slit formula 9 / 1 / 11, slit rays hardly or not indicated, teeth rather long, not pectinated, those of the tail valve much deformed, eaves narrow, porous. Girdle dorsally covered with close-set small (45 x 21 µm), blunt-topped spicules, with 10 – 11 ribs around, and scattered curved needles (39 – 42 x 5 µm). Marginal spicules slightly ribbed, round-topped up to 79 x 17 µm. Ventral side of girdle clothed with more or less rectangular scales (25 x 21 µm), ornamented around 12 – 13 distally converging riblets. Radula of the holotype was damaged, only the head of major lateral tooth is preserved, It has four denticles. Due to the fact that the holotype was damaged, it was not possible to calculate the number of gills.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFBDFFCFC9B878E14B8615A5.taxon	discussion	R e m a r k s. Despite the fact that this new species has a small size it looks like an adult chiton. Suffice it to recall a related species Tonicia disalvoi (Dell Angelo, Raines et Bonfitto, 2004) whose body length is two millimeters less. The present new species is most similar to Tonicia disalvoi that also has similar sculpture of tegmentum and not pectinated insertion plates, but differs from the latter in having ribbed ventral scales (vs. smooth scales in T. disalvoi), posterior mucro (vs. anterior mucro in T. disalvoi), jugal and most part of central area smooth (vs. with small pits in T. disalvoi), and curved shape of intermediate valves (vs. broadly rectangular in T. disalvoi).	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB1FFCFC9817ED048AB12E2.taxon	type_taxon	Ty p e s p e c i e s. Chiton undatus Quoy et Gaimard, 1835, non Wood, 1828 (= Onithochiton neglectus de Rochebrune, 1881) by subsequent designation by Gray, 1847.	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
03D387B6FFB1FFD4C9AB79B64BF11201.taxon	description	Figs. 9 – 11, 12 A urn: lsid: zoobank. org: act: 6376 B 502 - 81 F 9 - 4981 - 98 DA-E 83 BBFEC 8 DE 0 Ty p e m a t e r i a l. The holotype (ZISP 2305) now disarticulated, consisting of mount of part of girdle and radula, vial with valves, part of radula and part of girdle. Ty p e l o c a l i t y. Papua New Guinea, Astrolabe Bay, Bilibili Island, intertidal, rocks (R / V Kallisto, cruise 1, 03.01.1975, leg. B. I. Sirenko). E t y m o l o g y. Named in honour of the Russian ethnographer Nikolay Miklukho-Maklay, who studied the populations of South-East Asia, Australia and Oceania, including the indigenous tribes of North-Eastern Papua New Guinea in Astrolabe Bay. D i s t r i b u t i o n. Known only from the type locality. M a t e r i a l e x a m i n e d. Papua New Guinea, Astrolabe Bay, Bilibili Island, R / V Kallisto, cruise 1, intertidal, rocks, holotype (ZISP 2305), BL 36.0 mm, 1 paratype (ZISP 2306), BL 35 mm, 03.01.1975, leg. B. I. Sirenko. D i a g n o s i s. Animal of medium size, shell rounded. Tail valve narrower than head valve. Tegmentum of head valve, lateral area of intermediate valves, and postmucronal area of tail valve with round or oval, convex pustules (up to 300 – 400 µm) more or less arranged in radial rows at least in head valve. Central area with flattened riblets along diagonal line arranged longitudinally at the sides, anteriorly converging towards the jugum; interstices in two times narrower than riblets. There are distinct growth lines in all areas near anterior and side margins. Dorsal side of girdle beset with sharp-topped spicules, with longitudinal ribs around and scattered smooth needles. Major lateral tooth bearing a cusp with two denticles the outer denticle large, blunt and much rounded, the innermost small and sharp. D e s c r i p t i o n. The holotype 36.0 x 19.0 mm, elongated, oval, shell rather flat (dorsal elevation 0.25), rounded, slightly beaked. Color of tegmentum blackish-green in anterior margin of head valve, lateral and pleural areas of intermediate valves and hind margin of tail valve, other portion of central area and middle of head and tail valves yellow except red-brown in jugal area. Girdle yellow with reddish-brown spots. Head valve semicircular, hind margin straight, Intermediate valves rectangular, front margin convex in valve II and concave medially, convex at the pleurae in other valves, hind margin beaked, straight to concave at both sides of the strongly, bluntly protruding apex, lateral areas not raised, Tail valve considerably narrower than head valve, triangular, the length almost half the width, front margin straight, hind margin angularly rounded, mucro terminal, antemucronal slope convex, postmucronal area restricted to a narrow strip on both sides of the terminal mucro. Tegmentum of head valve, lateral area of intermediate valves and postmucronal area of tail valve with round or oval, convex pustules (up to 300 – 400 µm) more or less arranged in radial rows. Central area of intermediate valves and antemucronal area of tail valve with numerous flattish, longitudinal, forwardly converging ribs, interstices half as wide, ribs anteriorly converging, getting more fine and close set towards the very narrow, smooth jugum. Articulamentum white with light brown in the middle, apophyses well rounded, separated by wide finely pectinated sinus (23 small, short denticles in valve V), insertion plates of head and intermediate plates pectinated. Slit formula 8 / 1 / 0 (callus), slit rays slightly indicated. Girdle about 5.1 mm wide near valve V, dorsally covered with short, thick, sharp-topped spicules with 12 – 16 longitudinal riblets, 190 – 200 x 40 μm, among them randomly dispersed smooth needle 190 x 26 μm. Marginal spicules the same size. Ventral side of girdle covered with more or less rectangular scales with 18 - 20 distinct, distally converging riblets 60 x 28 µm. Radula of the holotype 11.0 mm long with 42 transverse rows of mature teeth, central tooth somewhat pinched in the middle with rectangular blade, first lateral tooth twice longer than central tooth, cusp of major lateral tooth with two denticles, the outer denticle large, blunt and much rounded, the innermost small and sharp. The holotype with 45 gills on both sides, extending from valve II to valve VIII. R e m a r k s. The present new species much resembles Australian Onithochiton quercinus (Gould, 1846), South African O. literatus (Krauss, 1848) and Vietnamese O. stracki Sirenko, 2012, but differs from them by having bidentate cusp of major lateral tooth of radula (vs. tetracuspid in all three), tegmentum of head valve, lateral area of intermediate valves, and postmucronal area of tail valve with round or oval, convex pustules (vs. irregular, flattish, concentric rugosites or transversely elongate, flattish nodules in all three). O. maclayi sp. nov. differs also from O. quercinus by having less number of longitudinal riblets and wider interstices between the riblets in central areas of intermediate valves. The new species differs from O. lyellii (Sowerby, 1832) and O. neglectus neglectus de Rochebrune, 1881 by having bidentate cusp of major lateral tooth of radula (vs. unicuspid cap in O. neglectus neglectus and tetracuspid cap in O. lyellii)	en	Sirenko, Boris I. (2019): New chitons (Mollusca: Polyplacophora) of the genera Rhyssoplax, Lucilina and Onithochiton from shallow waters of Papua New Guinea. The Bulletin of the Russian Far East Malacological Society 23 (1 / 2): 63-81, DOI: 10.5281/zenodo.11088070
