taxonID	type	description	language	source
C61387E91C51FFFC8C50EC7F1C3E0D2C.taxon	materials_examined	Type species. Sicyonella maldivensis Borradaile, 1910. Other species. Sicyonella antennata Hansen, 1919 and S. inermis (Paulson, 1875).	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C52FFF58C50EB951B5E0E3C.taxon	materials_examined	Type locality. Kai Islands, eastern part of the Banda Sea, Indonesia, 22 m. Type specimens. Hansen did not designate type series. Material examined. [USNM Collection] USNM­ 1026369: 1 male (cl 5.9 mm) and 2 females (cl 6.9 and 7.9 mm), Sitanki, Sibutu Island, Sulu Archipelago, Philippines, surface, electric light, 25 Feb. 1908, separated from USNM­ 260757. USNM­ 173562: 1 male (cl 7.6 mm) and 1 female (cl 7.7 mm), Singapore, date unknown. [NSMT Collection] NSMT­Cr 16021: 1 male (cl 5.4 mm), Nagura Bay, Ishigaki Island, Okinawa, Japan, seagrass bed, 2 – 3 m, light trap, 27 Dec. 1998, coll. M. Tamaki. NSMT­Cr 14116: 5 males (cl 3.4 – 5.3 mm), pier of Ishigaki Tropical Station of Seikai National Fisheries Research Institute (ITS), Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 1 Sept. 2000, coll. K. Fukuoka. NSMT­Cr 16022: 1 male (cl 5.6 mm), dissected, pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 18 Oct. 2000, coll. K. Fukuoka. NSMT­Cr 14117: 5 males (cl 4.3 – 4.9 mm), pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 5 Dec. 2000, coll. K. Fukuoka. NSMT­Cr 16023: 1 female (cl 5.7 mm), dissected, pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 26 Mar. 2001, coll. K. Fukuoka. NSMT­Cr 16024: 1 female (cl 5.8 mm), pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 26 Mar. 2001, coll. K. Fukuoka. NSMT­Cr 16025: 1 female (cl 6.9 mm), pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 23 Oct. 2001, coll. K. Fukuoka. NSMT­Cr 16026: 3 females (cl 4.0 – 5.3 mm), Ibaruma Bay, Ishigaki Island, Okinawa, Japan, fishing port, surface by hand­net under an electric light at night, 5 Nov. 2002, coll. K. Fukuoka. NSMT­Cr 16027: 1 female (cl 3.4 mm), pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 7 Nov. 2002, coll. K. Fukuoka.	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C52FFF58C50EB951B5E0E3C.taxon	description	Description. Carapace with postorbital and hepatic spines; pterygostomian spine small. Rostrum short, extending to or slightly beyond base of antennular peduncle, with 2 teeth on dorsal margin (Fig. 1 A – C). Abdomen smooth; sixth somite 1.8 – 1.9 times as long as fifth one, with indistinct dorsomedian carina except for posterior 0.3; pleuron of first to fifth somites expanded posteriorly, armed with setae on ventral margin. Telson tapering posteriorly to acute tip, 0.8 length of last abdominal somite, armed with 4 spines on distal 0.6 of ventral lateral margin (Fig. 3 K). Eye elongated, 1.9 – 2.3 times as long as wide of cornea in male, and 2 – 2.3 times as long as wide of cornea in female (Fig. 1 A, B). Cornea large, 2.2 – 2.9 times as wide as base of stalk in male and 2 – 2.4 times as wide in female (Fig. 1 A, B). Eyestalk gradually wider distally, without orbital spines (Fig. 1 A – C). Antennular peduncle elongate (Fig. 1 A, B). Stylocerite short, not extending to middle of first segment of peduncle (Fig. 1 A). First segment of antennular peduncle reaching distal 0.3 of scaphocerite, with anterolateral spiniform process (Fig. 1 A, B). Second segment of antennular peduncle shows sexual dimorphic; in male long, overreaching apex of scaphocerite, 0.5 – 0.8 length of first segment, 2.6 – 3.5 times as long as wide (Fig. 1 A); in female robust, not reaching apex of scaphocerite, 0.4 – 0.5 length of first, 1.7 – 2.4 times as long as wide (Fig. 1 B). Third segment of antennular peduncle shows sexual dimorphic, elongated and 1 – 1.4 times longer than second segment in male, 0.9 – 1.1 times as long as second in female (Fig. 1 A, B). Distal two segments of antennular peduncle 1 – 1.7 times as long as proximal segment in male, and 0.8 – 1.1 times as long as proximal segment in female (Fig. 1 A, B). Mesial antennular flagellum of male with modified proximal part (Fig. 4 A); first segment armed on upper margin with 3 long, rather stout setae (Fig. 4 B); second segment short, armed on upper margin with 2 stout setae branched in terminal end (Fig. 4 B, C); third segment elongate, upper margin concave (Fig. 4 A), with 1 stout seta on pre­depression (Fig. 4 A, B), with 1 stout and 1 slender setae in middle (Fig. 4 A, D), and with 3 robust and 1 stout setae on post­depression, robust setae on post­depression scaly on posterior surface of distal part (Fig. 4 A, E). Scaphocerite 3.6 – 3.7 times as long as wide, apical lobe triangular with rounded apex (Fig. 1 D). Antennal peduncle robust, extending to proximal 0.4 of scaphocerite (Fig. 1 D). Mandible with flattened, 3 ­ segmented palp; second segment of palp expanded in middle; third segment of palp 0.4 of second segment in length, 2 – 2.3 times as long as wide (Fig. 1 E). Incisor process developed, with acute process on distomesial corner, mesial margin smooth, divided into two portions (Fig. 1 E). Maxillule with proximal endite spatulate with 3 long and several rather long, robust, spiniform setae on distal margin; distal endite broadened mesially, armed with numerous strong, spiniform setae on distal and mesial margins, and with long and short spiniform setae on distal half of lateral margin; endopod elongate, armed with 1 long, robust, naked, spiniform seta near apex of mesial margin and with 5 – 7 plumose setae on distal 0.3 of lateral margin to apex (Fig. 1 F). Maxilla with endopod tapering distally, armed with 6 – 9 short spines on distal part; endite rudimentary; scaphognathite large, with rounded anterior and posterior lobes, armed densely with plumose setae on margin (Fig. 1 G). First maxilliped with endopod long, slender, 3 ­ segmented, armed with 2 or 3 long spines on proximal expanded part; exopod large; epipod large, not bilobed; distal endite large, broadened distally, armed densely with setae on margin; proximal endite represented by two similar lobes, small, armed with setae on mesial margin (Fig. 2 A). Second maxilliped without exopod and epipod. Ischium of endopod 1.1 – 1.3 times as long as merus; merus as long as carpus; distal 3 segments gradually shorter in length distally (Fig. 2 B). Third maxilliped long, robust, extending to distal 0.3 of distal segment of antennular peduncle in male, and extending beyond distal end of antennular peduncle in female; ischium armed with short setae on mesial and lateral margins; merus 0.7 – 0.8 of ischium in length; carpus 1.1 – 1.2 times as long as merus; propodus as long as carpus, 3 ­ subsegmented by indistinct articulations; dactylus 0.7 – 0.8 length of carpus, 4 ­ subsegmented by indistinct articulations, terminating to robust, spiniform seta; distal 4 segments armed with short and long, robust, spiniform setae on mesial and lateral margins (Fig. 2 C). First pereopod reaching middle of merus of third maxilliped, chelate; merus indistinctly divided from ischium; carpus slightly shorter than merus, armed on distal 0.3 of mesial surface with brushing setae arranged in a V­shape; propodus slightly shorter than carpus, armed with short and long brushing setae on proximal 0.3 – 0.4 of lower side of mesial surface; dactylus 0.7 of palm length, as long as propodal finger; cutting edge sparsely armed with minute setae (Fig. 2 D, E). Second pereopod 1.3 times as long as first pereopod, chelate; merus indistinctly divided from ischium; carpus 1.3 times as long as merus, armed with small spines on distal half of lower margin; propodus 0.7 – 0.8 length of carpus, armed with minute, spiniform setae on near proximal end of lower margin; dactylus 0.4 of palm length, similar to propodal finger; cutting edge sparsely armed with minute setae (Fig. 2 F, G). Third pereopod 1.3 – 1.4 times longer than second pereopod, chelate; merus divided from ischium by oblique articulation; carpus 1.7 times as long as merus, sparsely armed with spines on distal 0.2 of lower margin; propodus 0.7 of carpus in length; dactylus 0.3 – 0.4 of palm length, as wide as propodal finger; cutting edge sparsely armed with short setae (Fig. 2 H, I). Fourth pereopod 7 ­ segmented, 0.7 length of third pereopod, no chelate; ischium and merus armed with long plumose setae on lower and upper margins, merus 1.6 times as long as ischium; carpus and propodus armed with long plumose setae on lower margin; dactylus terminating in small claw (Fig. 2 J). Fifth pereopod 7 ­ segmented, 0.7 – 0.8 length of fourth pereopod, similar to fourth pereopod in shape and armature (Fig. 2 K). First pleopod lacking endopod; second to fifth pleopods biramous, exopod longer than endopod (Fig. 3 A, D, F, H). Sympod armed on distomesial angle with 2 or 3 short, plumose setae in second pleopod (Fig. 3 C), with long spiniform seta in third pleopod (Fig. 3 D, E), with extremely long, robust, posteriorly curved, spiniform seta in fourth pleopod (Figs. 3 F, G, 5 A, B), and with 2 – 6 short and long, spiniform setae in fifth pleopod (Figs. 3 H, I, 5 C, D), setae in fourth and fifth pleopods serrated in distal half (Fig. 5 B, D). Appendix interna present on proximal part of endopod of second male pleopod, robust, reaching proximal 0.4 of endopod, armed with 4 long and 4 short spines on distal margin (Fig. 3 A, B). Uropodal endopod extending beyond apex of telson; uropodal exopod 1.2 – 1.3 times as long as endopod (Fig. 3 K). Petasma of male developed (Figs. 3 J, 4 F – H). Processus unicifer (pu) 0.4 length of lamina externa, narrow, tapering to rounded apex (Fig. 3 J). Processus ventralis (pv) very long, divided into 2 branches (Figs. 3 J, 4 F); posterior branch long, terminating into 2 secondary branches, mesial secondary branch short, armed with several hooks, lateral one directed laterally, longer than broad, armed with a few hooks on near end and distal end respectively (Fig. 4 F, G); anterior branch shorter than posterior one, narrow except expanded terminal part, divided into 2 secondary branches (Fig. 3 J, 4 F). Lobus terminalis (lt) long, nearly spirally twisted, wrinkled (Figs. 3 J, 4 F). Lobus connectens (lc) cylindrical, slender, with terminal hook (Fig. 3 J). Lobus inermis (li) almost as long as lobus connectens, robust, tapering distally, with terminal hook (Fig. 3 J). Lobus armatus (lar) and lobus accessorius (lac) with terminal hook (Figs. 3 J, 4 F, H). Thelycum of female (Fig. 5 E): sternite of sixth thoracic somite with pair of small, acute protuberances on posterior surface (Fig. 5 E, H); sternite of seventh thoracic somite projected laterally just in front of base of fourth pereopod (Fig. 5 E, H); coxa of third pereopod armed with several plumose setae on lateral surface, opened oviduct bearing several slender setae on lateral margin and a few short setae on lateral part of upper margin (Fig. 5 F, G). Color. Body transparent with scattered red chromatophores. Antennal flagellum with single red band in stiff proximal portion (Fig. 17 A).	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C52FFF58C50EB951B5E0E3C.taxon	distribution	Distribution. Sicyonella antennata is recorded from East and Southeast Asia: Indonesia, the Gulf of Thailand (Hansen, 1919), Japan (Hayashi, 1992; this study), Singapore and the Philippines (USNM collection). This species was collected from depths of 7 – 22 m (Hansen, 1919) and from a seagrass bed (Hayashi, 1992; this study).	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C52FFF58C50EB951B5E0E3C.taxon	discussion	Remarks. Sicyonella antennata was originally described from one male and one female specimen collected from off the Kai Islands, Indonesia, and several specimens collected from the Gulf of Thailand and deposited in the Copenhagen Museum (Hansen, 1919). Subsequently, Hayashi (1992) recorded this species from a seagrass bed at Iriomote Island, Yaeyama Islands, Okinawa, southwestern Japan. The present Japanese specimens agree with the original description and illustrations by Hansen (1919), except for the length of the antennular peduncle. In Hansen’s (1919) original description, the mesial margin of the combined length of the distal two segments is somewhat less than twice as long as that of the proximal segment in the male (bl 25 mm), and is distinctly longer than that of the proximal segment in the female (max. bl 31.5 mm). That of the Japanese specimens is shorter than Hansen’s description: 1.7 and 1.1 times as long as the proximal segment in the male and female, respectively. In the Japanese specimens, the length of the distal two segments varies with body length. This character seems to vary with season, also. The combined length of the distal two segments was longer in individuals collected in September than in December (Fig. 6). The morphological development of the petasma also varied by seasons: it was perfectly development in the September specimen (cl 4.5 mm) and imperfect in the December specimen (cl 4.9 mm). These seasonal differences are probably caused by fluctuations in the growth rate with temperature.	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C5BFFED8C50E8851BE20DE4.taxon	materials_examined	Type locality. Red Sea. Type specimen. Location of specimen unknown. Material examined. [NHM Collection] NHM (1912.2.10.135): 1 female (cl 7.2 mm), one of syntype of S. maldivensis, Cargados Carajos, Mauritius, date unknown. NHM (1913.5.19: 8): 1 male (cl 5.1 mm), holotype of Aphareocaris elegans, Thursday Island, Torres Straits, date unknown. NHM (1938.1.28: 75 – 77): 5 females (cl 3.8 – 7.3 mm), near Biological Station of University of Egypt at Ghardaqa, Red Sea, on Halophila, Feb. 1936, coll. R. Gurney. [USNM Collection] USNM­ 1026370: 2 females (cl 7.3 mm and broken), Sitanki, Sibutu Island, Sulu Archipelago, Philippines, surface, electric light, 25 Feb. 1908, separated from USNM­ 260757. USNM­ 89840: 1 male, Persian Gulf, Ras Tanura, Saudi Arabia, 26 Apr. 1948, coll. D. S. Erdman. USNM­ 89841: 2 males (cl 5.0 and 5.1 mm) and 4 females (cl 4.2 – 4.5 mm), Persian Gulf, Ras Tannurah, north of Bahrein, Saudi Arabia, 13 June 1948, coll. D. S. Erdman. USNM­ 89842: 1 female, Persian Gulf, Ras Tanura, Saudi Arabia, May­June 1948, coll. D. S. Erdman. [NSMT Collection] NSMT­Cr 16028: 2 males (cl 6.0 and 6.2 mm), Nagura Bay, Ishigaki Island, Okinawa, Japan, seagrass bed, 2 – 3 m, light trap, 27 Dec. 1998, coll. M. Tamaki. NSMT­Cr 16029: 3 males (cl 4.1 – 4.8 mm), pier of Ishigaki Tropical Station of Seikai National Fisheries Research Institute (ITS), Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 7 Nov. 2000, coll. K. Fukuoka. NSMT­Cr 14114: 4 males (cl 4.5 – 6.2 mm), pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 5 Dec. 2000, coll. K. Fukuoka. NSMT­Cr 16030: 1 male (cl 5.3 mm), dissected, pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 8 Dec. 2000, coll. K. Fukuoka. NSMT­Cr 16031: 1 female (cl 5.4 mm), pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 8 Dec. 2000, coll. K. Fukuoka. NSMT­Cr 16032: 1 female (cl 7.9 mm), pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 26 Mar. 2001, coll. K. Fukuoka. NSMT­Cr 16033: 4 females (cl 3.7 – 6.8 mm), Shiraho Coral Reef moat, Ishigaki Island, Okinawa, Japan, sand bottom among coral, 3 m, hand­net under an electric light at night, 16 July 2001, coll. K. Fukuoka. NSMT­Cr 16034: 3 females (cl 3.6 – 6.3 mm), Aka­shin­ko, Aka­jima Island, Okinawa, Japan, port, surface by hand­net under an electric light at night, 3 Oct. 2002, coll. K. Fukuoka. NSMT­Cr 16035: 1 female (cl 5.7 mm), dissected, pier of ITS, Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 – 3 m, light trap, 7 Nov. 2002, coll. K. Fukuoka.	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C5BFFED8C50E8851BE20DE4.taxon	description	Description. Carapace with postorbital and hepatic spines; anterolateral corner produced into small pterygostomian spine. Rostrum extending to base of antennular peduncle, with 2 teeth on dorsal margin (Fig. 7 A – C). Abdominal somite smooth; first to fifth somites with pleuron expanded posteriorly bearing setae on margin; sixth somite 2.2 times as long as fifth one, with indistinct dorsomedian carina. Telson elongate, triangular, 2.5 – 3.7 times as long as wide, armed with 4 spines and numerous long, plumose setae on distal 0.5 of ventrolateral margin (Fig. 9 L). Eye elongated, 2.4 – 2.9 times as long as wide of cornea (Fig. 7 A, B). Cornea of eye occupying 0.2 – 0.3 of eye in length, 1.8 – 2 times as wide as base of stalk (Fig. 7 A, B). Eyestalk gradually wider distally, without orbital spines (Fig. 7 A, B). Antennular peduncle robust, elongate (Fig. 7 A, B). Stylocerite not reaching middle of first segment of peduncle (Fig. 7 A, B). First segment of antennular peduncle extending to distal 0.3 of scaphocerite, with anterolateral spiniform process (Fig. 7 A, B). Second segment of antennular peduncle rather short, 0.4 – 0.5 length of first segment in male and 0.4 length of first in female, 1.6 – 2 times as long as wide in male and 2 – 2.3 times as long as wide in female, with 1 or 2 short spines on anterolateral angle of dorsal surface (Fig. 7 A, B, D). Third segment of antennular peduncle rather short, 0.8 – 1 times as long as second segment in both sexes, 2.1 – 2.6 times as long as wide (Fig. 7 A, B). Distal two segments of antennular peduncle 0.7 – 0.9 of proximal segment in length (Fig. 7 A, B). Mesial antennular flagellum of male modified in proximal portion (Fig. 10 A); proximal 2 segments short, third segment armed with 2 long setae on anteromesial angle, fourth segment long, expanded laterally with scaly surface (Fig. 10 A – C). Scaphocerite 3.3 – 3.6 times as long as wide, with rounded apical lobe (Fig. 7 E). Antennal peduncle robust, extending to proximal 0.4 of scaphocerite (Fig 7 E). Mandibular palp flattened, divided into 3 segments; second segment expanded in middle; third segment 0.3 length of second one, 2 – 2.2 times as long as wide (Fig. 7 F). Maxillule with proximal endite longer than wide, armed with 3 long, setose and several long, naked setae on distal part; distal endite expanded mesially; endopod narrow, 3.5 times as long as wide, armed with long, naked, spiniform seta on near apex of mesial margin and with 2 or 3 plumose setae on near apex of lateral margin (Fig. 7 G). Maxilla with endopod tapering distally and armed with 8 or 9 spines on distal part; endite rudimentary; scaphognathite large, armed densely with plumose setae on entire margin (Fig. 7 H). First maxilliped with endopod long, slender, 2 ­ segmented, and armed with 3 long spines on proximal expanded part; exopod large; epipod no bilobed; distal endite broadened anteriorly, densely armed with setae on margin; proximal endite divided into two lobes (Fig. 8 A). Second maxilliped without exopod and epipod; endopod similar to S. antennata (Fig. 8 B). Third maxilliped long, robust, extending beyond distal end of antennular peduncle; ischium armed with short setae on mesial and lateral margins; merus 0.7 – 0.8 of ischium in length; carpus 1.1 times as long as merus; propodus 1.1 times longer than carpus, 3 ­ subsegmented; dactylus 0.8 length of carpus, 4 ­ subsegmented, with long, strong, spiniform claw on terminal end; distal 4 segments armed with short and long, robust setae on mesial and lateral margins (Fig. 8 C). First pereopod extending to middle of merus of third maxilliped, chelate; carpus armed with brushing setae on distal 0.3 of mesial surface, these setae arranged in a V­shape; propodus slightly longer than carpus, armed on proximal 0.3 of lower side of mesial surface with double row of brushing setae, which are composed of short naked and rather long plumose setae; dactylus occupying 0.4 of propodus length, same size with propodal finger (Fig. 8 D, E). Second pereopod 1.3 – 1.4 times as long as first pereopod, chelate; carpus 1.1 – 1.2 times longer than merus, armed with 5 or 6 small spines on distal 0.2 of lower margin; propodus 0.7 – 0.8 of carpus length, armed with 4 or 5 short spiniform setae on proximal 0.1 of lower margin; dactylus occupying 0.4 of propodus length (Fig. 8 F, G). Third pereopod 1.2 – 1.3 times as long as second pereopod, chelate; carpus 1.6 times longer than merus; propodus 0.7 length of carpus, 11 times as long as wide; dactylus occupying 0.3 of propodus in length (Fig. 8 H). Fourth and fifth pereopods developed, 7 ­ segmented, not chelate, armed with long plumose setae on lower and upper margins in ischium and merus and on only lower margin in carpus and propodus, terminating into small claw on dactylus (Fig. 8 I, J). First pleopod without endopod (Fig. 9 A); second to fifth pleopods with endopod and exopod, exopod longer than endopod (Fig. 9 B, E, G, I). Distomesial corner of sympod of second pleopod armed with 1 or 2 tiny setae (Figs. 9 D, 11 A); that of third pleopod with rather short, spiniform seta (Fig. 9 F); that of fourth pleopod with long, robust, posteriorly curved, spiniform seta, which is serrated in distal half (Figs. 9 H, 11 B, C); that of fifth pleopod with long, robust, almost straight, spiniform seta (Figs. 9 J, 11 D). Appendix interna present on base of exopod of second male pleopod, armed with 4 long spines on distal margin (Fig. 9 B, C). Uropodal endopod extending beyond telson by 0.3 of its length; exopod 1.3 times longer than endopod (Fig. 9 L). Processus unicifer (pu) of petasma of male short, 0.1 of laminal externa in length, tapering to rounded apex (Fig. 9 K); pars media (pm) simplified, tip of capitulum curved mesially, mesial surface from tip to posterior 0.3 with hooks (Figs. 9 K, 10 D, E). Thelycum of female not modified (Fig. 10 F); coxa of third pereopod smooth on lateral surface, with oviduct opening armed with several long, naked setae on lateral margin and several plumose setae on upper margin (Fig. 10 G).	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C5BFFED8C50E8851BE20DE4.taxon	description	Distirbution. After reexamining two syntype specimens of S. maldivensis, one male from the Maldives and one female from Cargados Carajos, Mauritius, lodged in NHM, the female specimen (NHM 1912.2.10.135) was identified as S. inermis from the shape of the thelycum and the setation of the sympod of the pleopods. This species is recorded from the Red Sea (Paulson, 1875; Balss, 1915; Burkenroad, 1937), Mauritius (Borradaile, 1910), the Torres Strait (Calman, 1913), Indonesia (De Man, 1922), Sri Lanka (Burkenroad, 1937), the Persian Gulf (Chace, 1955), the Philippines (USNM collection), and Japan (this study). This species was collected in offshore water with a plankton net (Balss, 1915; De Mann, 1922), in a dredge at night, and from a seagrass bed, Halophila, at a depth of 7 m (Burkenroad, 1937). Japanese specimens were collected from a seagrass bed or the sandy bottom area of a coral reef moat, shallower than 10 m.	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C5BFFED8C50E8851BE20DE4.taxon	discussion	Remarks. Sicyonella inermis was established by Paulson (1875) under the name Aphareus inermis, and was briefly described on a single specimen (sex unknown) collected from the Red Sea. Subsequently, Calman (1913) described this species in detail based on a single male specimen, which was named Aphareocaris elegans, collected from Thursday Island, Torres Straits. Calman (1914) degraded A. elegans into the junior synonym of S. maldivensis because he considered A. elegans an immature form of S. maldivensis. Hansen (1919) doubted its state, but retained it. In 1937, Burkenroad examined specimens of S. inermis collected from Sri Lanka and the Red Sea, and synonymized A. elegans with S. inermis. The number of teeth on the dorsal margin of the rostrum has been given as one (Paulson, 1875) or two (Calman, 1913; Balss, 1915; De Mann, 1922). All of the specimens that we examined have two teeth. The telson was described with four pairs of marginal spines in Paulson (1875) and De Mann (1922), and with five pairs in Calman (1913). All of the specimens that we examined have four pairs of marginal spines.	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C43FFE58C50E85D1A760DE4.taxon	materials_examined	Type locality. North Male Atoll, Maldives. Type specimen. Lectotype: NHM (1987.10.1), male (cl 7.0 mm), one of syntype of S. maldivensis, North Male Atoll, Maldives, date unknown. Material examined. [USNM Collection] USNM­ 260757: 14 males (cl 6.1 – 7.2 mm) and 5 females (cl 7.3 – 9.5 mm), Sitanki, Sibutu Island, Sulu Archipelago, Philippines, surface, electric light, 25 Feb. 1908. USNM­ 94725: 1 female (cl 7.8 mm), Bikini Lagoon, light at night, 23 Apr. 1946, coll. Schultz and Morrison. USNM­ 94726: 1 male, Bikini Lagoon, marine light, anchorage, 25 Apr. 1946, coll. Schultz. USNM­ 105267: 1 female (cl 5.8 mm), Palau Islands (7 ° 19 ’ 34.5 ’’ N 134 ° 28 ’ 05 ’’ E), 16 Aug. 1955. USNM­ 105229: 1 male (cl 5.1 mm) and 1 female (cl 7.5 mm), Yoo Passage (7 ° 12 ’ 00 ’’ N 134 ° 25 ’ 42 ’’ E), west of Kasso Reef, Palau Islands, 27.5 – 32.9 m, dredge, 24 Aug. 1955. USNM­ 266986: 1 male (cl 5.0 mm), Parry Island, Marshall Islands, lagoon, 28 Aug. 1956. [MNHN Collection] MNHN: 1 male and 1 female, St. DW 1116, New Caledonia, date unknown. [NSMT Collection] NSMT­Cr 14115: 5 males (cl 3.9 ­ 4.5 mm), pier of Ishigaki Tropical Station of Seikai National Fisheries Research Institute (ITS), Urasoko Bay, Ishigaki Island, Okinawa, Japan, sand bottom, 2 ­ 3 m, light trap, 1 Sept. 2000, coll. K. Fukuoka. NSMT­Cr 16036: 1 male (cl 5.6 mm), dissected, Aka­shin­ko, Aka­jima Island, Okinawa, Japan, port, surface by hand­net under an electric light at night, 2 Oct. 2002, coll. K. Fukuoka. NSMT­Cr 16037: 1 female (cl 6.7 mm), dissected, Aka­shin­ko, Aka­jima Island, Okinawa, Japan, port, surface by hand­net under an electric light at night, 3 Oct. 2002, coll. K. Fukuoka. NSMT­Cr 16038: 3 males (cl 4.3 – 6.3 mm) and 1 female (cl 5.9 mm), Kise, Kasari, Amami­oshima Island, Kagoshima, Japan, fishing port, sand­mud bottom, 1 m, hand­net under an electric light at night, 23 July 2003, coll. K. Fukuoka. NSMT­Cr 16039: 1 female (cl 6.3 mm), Kise, Kasari, Amami­oshima Island, Kagoshima, Japan, fishing port, sand­mud bottom, 1 m, hand­net under an electric light at night, 25 July, 2003, coll. K. Fukuoka. NSMT­Cr 16040: 1 female (cl 6.6 mm), Aka­shin­ko, Aka­jima Island, Okinawa, Japan, port, surface by hand­net under an electric light at night, 24 Sept. 2003, coll. K. Fukuoka. NSMT­Cr 16041: 1 female (cl 5.7 mm), Aka­shin­ko, Aka­jima Island, Okinawa, Japan, port, surface by hand­net under an electric light at night, 26 Sept. 2003, coll. K. Fukuoka.	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C43FFE58C50E85D1A760DE4.taxon	description	Description. Carapace with pterygostomian, postorbital and hepatic spines. Rostrum extending to base of antennular peduncle, with 2 teeth on dorsal margin (Fig. 12 A­C). Abdomen smooth; sixth somite twice as long as fifth one, with indistinct dorsolateral sulcus; pleuron of first to fifth somites expanded posteriorly, armed with setae on ventral margin. Telson tapering posteriorly, armed with 4 spines and numerous long, plumose setae on distal half of ventrolateral margin (Fig. 14 M). Eye elongate, 4.7 – 5.2 times as long as wide of base of stalk, 2 – 2.3 times as long as wide of cornea in male and 2.3 – 2.6 times as long as wide of cornea in female (Fig. 12 A, B). Cornea of eye 2.1 – 2.6 times as wide as base of stalk in male, and 1.8 – 2 times as wide as base of stalk in female (Fig. 12 A, B). Eyestalk gradually wider distally, without orbital spines (Fig. 12 A – C). Antennular peduncle robust (Fig. 12 A, B). Stylocerite not reaching middle of first segment of peduncle (Fig. 12 A, B). First segment of antennular peduncle extending to distal 0.3 of scaphocerite, with anterolateral spiniform process (Fig. 12 A, B). Second segment of antennular peduncle of both sexes 0.4 – 0.5 length of first segment, 1.9 – 2.4 times as long as wide, with 1 – 3 short spines on anterolateral angle (Fig. 12 A, B, D). Third segment of antennular peduncle of both sexes 0.8 – 1.1 times as long as second segment, 2.5 – 3.3 times as long as wide (Fig. 12 A, B). Distal two segments of antennular peduncle 0.8 – 1.1 times as long as proximal segment (Fig. 12 A, B). Mesial antennular flagellum of male modified in proximal portion (Fig. 15 A); first and second segments short, armed on upper margin with 5 and 2 robust setae, respectively, these setae branching in terminal end (Fig. 15 A, B); third segment long (Fig. 15 A), upper margin concave, pre­depression with 2 rather short, robust setae branching in terminal end, middle part naked, post­depression with 10 robust setae, proximal 8 setae gradually increasing in length anteriorly, scaly on posterior surface of distal part (Fig. 15 C), anterior 2 setae without such structure (Fig. 15 D). Scaphocerite 3.5 – 3.6 times as long as wide, with triangular apical lobe (Fig. 12 E). Antennal peduncle extending to proximal 0.4 of scaphocerite (Fig. 12 E). Mandibular palp flattened, divided into 3 segments; second segment expanded in middle; third segment 0.3 length of second one (Fig. 12 F). Maxillule with proximal endite longer than wide and armed with 3 or 4 long, robust, spiniform setae and several short setae on distal margin; distal endite expanded mesially; endopod tapering apically, armed with long, robust, naked, spiniform seta on near apex of mesial margin, and with 3 – 5 plumose setae on distal 0.3 of lateral margin to apex (Fig. 12 G). Maxilla with endopod tapering distally and armed with 8 short, robust spines on distal part; endite rudimentary; scaphognathite large, armed with plumose setae on entire margin (Fig. 12 H). First maxilliped with 3 ­ segmented endopod armed with 2 long, stout spines on proximal expanded part; exopod leaf­shaped; epipod no bilobed; distal endite broadened anteriorly; proximal endite represented by two similar lobes (Fig. 13 A). Second maxilliped without exopod and epipod; similar to S. antennata and S. inermis (Fig. 13 B). Third maxilliped long, extending beyond distal end of antennular peduncle, similar to S. antennata and S. inermis (Fig. 13 C). First pereopod extending to middle of merus of third maxilliped, chelate; carpus armed with brushing setae arranged in a V­shape on distal 0.2 of mesial surface; propodus armed with double row of brushing setae on proximal 0.3 of lower side of mesial surface; dactylus occupying 0.4 of propodus length (Fig. 13 D). Second pereopod 1.3 – 1.4 times as long as first pereopod, chelate; carpus armed with 8 – 10 small spines on distal 0.2 of lower margin; propodus armed with 5 or 6 serrated, small spines on proximal 0.2 of lower margin (Fig. 13 E, F). Third pereopod 1.3 times longer than second pereopod, chelate; carpus 1.7 – 1.9 times as long as merus; propodus 0.7 of carpus length; dactylus 0.3 of propodus length (Fig. 13 G). Fourth pereopod 0.7 times as long as third pereopod (Fig. 13 H). Fifth pereopod 0.8 of fourth pereopod in length (Fig. 13 I). Fourth and fifth pereopods not chelate, armed with long plumose setae on lower and upper margins of ischium and merus and on only lower margin of carpus and propodus, terminating small claw on dactylus (Fig. 13 H, I). First pleopod without endopod (Fig. 14 A); second to fifth pleopods with endopod and exopod (Fig. 14 B, E, G, H). Endopod of second male pleopod with appendix interna armed with 2 long and 3 short spines on distal margin (Fig. 14 B, C). Distomesial angle of sympod armed with 2 short, plumose setae in second pleopod (Fig. 14 D), with tiny spiniform seta in third pleopod (Figs. 14 F, 16 A), with extremely long, robust, posteriorly curved, spiniform seta in fourth pleopod (Fig. 14 G), and with 2 – 6 short and long, spiniform setae in fifth pleopod (Figs. 14 H, I, 16 B – D), setae on fourth and fifth pleopods serrated in distal half (Fig. 16 C, D). Uropodal endopod extending beyond apex of telson by 0.3 of its length; uropodal exopod 1.3 times longer than endopod (Fig. 14 L). Processus unicifer (pu) of petasma of male less than half of lamina externa, broad, with rounded apex (Fig. 14 J, K). Processu ventralis (pv) divided into 2 branches in near base (Fig. 14 J, K); ventral branch divided into 2 secondary branches in near middle, lateral secondary branch slender, almost straight, terminating into hook, mesial one longer than lateral one, expanded and curved laterally in distal third, terminating into hook (Fig. 15 F); dorsal branch shorter than ventral branch, expanded laterally. Lobus terminalis (lt) short (Fig. 14 J, K). Lobus connectens (lc) short, tapering distally, terminating into hook (Fig. 14 J, K). Lobus armatus (lar) strong, directed laterally, with strong hook on near apex of anterior surface and several small hooks on terminal part (Figs. 14 J, K, 15 E, G). Thelycum of female with acute process on just posterior to base of third pereopod (Fig. 16 E, F); coxa of third pereopod armed with several plumose setae on lateral surface, opened oviduct bearing several long, naked setae on lateral margin but smooth on upper margin (Fig. 16 G). Color. Body transparent with scattered red chromatophores. Antennular and antennal flagellums without red bands (Fig. 17 C).	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C43FFE58C50E85D1A760DE4.taxon	distribution	Distribution. This species has been recorded from the Maldives (Borradaile, 1910), Indonesia (Hansen, 1919), the Red Sea (Cecchini, 1933), the Marshall Islands (Chace, 1955), New Caledonia (MNHN collection), the Palau Islands, the Philippines (USNM collection), and Japan (this study). This species has been collected from depths of 12 – 55 m (Hansen, 1919; USNM collection data) by dredge, trawl, or plankton net, and from shallow water by dip net with an electric light at night (USNM collection data). The Japanese specimens were collected from a coral reef moat and fishing port at night using an electric light.	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
C61387E91C43FFE58C50E85D1A760DE4.taxon	discussion	Remarks. Borradaile (1910) established S. maldivensis based on specimens collected from the Maldives and Cargados Carajos, Mauritius. Two syntype specimens, one male from the Maldives and one female from Cargados Carajos, were lodged in NHM. We reexamined these syntype specimens and identified the female specimen as S. inermis. Therefore, this study designates a lectotype of S. maldivensis based on the male specimen (NHM 1987.10.1) from the Maldives. Borradaile (1910) briefly described S. maldivensis. Subsequently, Hansen (1919) recorded this species from Indonesian waters, and described several characters in detail. The Japanese specimens agree with these descriptions. Chace (1955) first observed the thelycum of S. maldivensis in specimens from Bikini, and described and illustrated a prominent, bidentate structure immediately posterior to the coxa of the third pereopod. However, in our observation of specimens from Japan, the Philippines, and Palau, there is only a single denticle. The thelycum of a specimen from Bikini deposited in the USNM (USNM 94725) could not be observed because that portion has been dissected and is missing from the bottle.	en	Fukuoka, Kouki, Tamaki, Motoya, Kikuchi, Tomohiko (2005): (Crustacea: Decapoda: Dendrobranchiata: Sergestidae). Zootaxa 833: 1-31, DOI: 10.5281/zenodo.170671
