taxonID	type	description	language	source
03F54170FFCFFFC8FF33B00EDA9799F1.taxon	description	(Figs. 3 – 5)	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFCFFFC8FF33B00EDA9799F1.taxon	materials_examined	Material examined. CBM-ZC 11652, 1 intersex (cl 8.3 mm), Atetsu, Setouchi, Amami-ohshima Island, Ryukyu Islands, 28.1892 N, 129.2899 E, intertidal, tidal flat with gravel, 30 April 2006, yabby pump, coll. T. Komai; CBM-ZC 11653, 2 intersex (cl 6.4, 8.3 mm, DNA voucher 1495), Shinokawa, Setouchi, Amami-ohshima Island, tidal flat, 30 April 2006, yabby pump, coll. T. Komai; CBM-ZC 10291, 1 intersex (cl 6.4 mm), Red Beach, Kin, Okinawa Island, Ryukyu Islands, 10 m, sand bottom under rock, 4 March 2009, SCUBA diving, coll. Y. Yamada; CBM-ZC 10292, 1 intersex (cl 7.3 mm; DNA voucher 1496), same locality, 10 m, sand bottom under rock, 25 March 2009, SCUBA diving, coll. Y. Yamada.	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFCFFFC8FF33B00EDA9799F1.taxon	description	Description of Japanese specimens. Rostrum (Fig. 3 A, B) moderately long, overreaching distal corneal margins by 0.3 – 0.4 length, subtriangular in dorsal view, nearly as broad as long or slightly longer than broad at base, directed forward, straight in lateral view; dorsolateral margins with 2 pairs of moderately strong, obliquely erect spines of nearly equal size; ventral surface unarmed. Carapace (Fig. 3 A, B) with posteriorly divergent gastric lateral ridges not produced anteriorly, each bearing 10 – 13 spines or tubercles reducing in size and sharpness posteriorly. Shoulder lateral to cervical groove not ornamented; linea thalassinica continuing to posterior carapace margin. Postocular margin with 1 small spine (postocular spine). Epistomial projection (Fig. 3 A) rather broad in lateral view, bearing 1 small spine on either side. Pleonal sternites unarmed. Sixth pleomere posterior margin (Fig. 3 C) smooth, without denticles or granules. Telson (Fig. 3 C) trapezoidal, bearing prominent transverse proximal ridge confluent with longitudinal ridge at each side on dorsal surface; lateral margins subparallel in anterior 0.3 and gently concave thereafter; posterior margin nearly straight or faintly concave medially. Ocular peduncle (Fig. 3 A) stout, unarmed distomesially; cornea slightly narrower than proximal diameter of ocular peduncle. Antennular peduncle (Fig. 3 A) reaching to midlength of fifth article of antennal peduncle; proximal 2 articles together subequal in length to third article, first article with tiny spine at ventromesial distal angle. Antennal peduncle (Fig. 3 A) extending beyond tip of rostrum by half-length of fourth article; all but second article spineless, second article with conspicuous ventromesial distal spine; scaphocerite moderate, suboval with 2 spinules on distolateral margin. Third maxilliped without epipod. First pereopod (cheliped) (Fig. 4 A – F) moderately stout. Coxa with slender, ventrally directed spine on mesial margin. Ischium bearing 1 or 2 small spines on ventral margin laterally. Merus with row of about 10 spinules or denticles markedly reducing in size and sharpness distally on ventral to ventromesial margin; dorsal margin convex, with 1 small subdistal spine. Carpus trigonal, with shallow longitudinal groove on lateral surface; flexor distal corner with 2 small spines; extensor distal margin armed with 4 small spines (Fig. 4 D); extensor mesial margin not crested, but with 4 small spines, partly obscured by setae in proximal part (Fig. 4 D); distomesial margin armed with 2 prominent spines, upper spine at dorsal corner much stronger than lower spine. Carpus-chela articulation somewhat twisted. Palm about 2.2 times as long as wide; dorsal surface with longitudinal row of small spines or spiniform tubercles decreasing in size and sharpness proximally, but proximalmost spine acuminate (Fig. 4 E); distomesial margin minutely denticulate, mesial dactylar condyle armed with small but conspicuous spine (Fig. 4 F); lateral dactylar condyle well marked; lateral surface with oblique line of plumose setae extending from mid-proximal margin to slightly beyond midlength on ventral surface; ventral surface armed with 1 strong spine arising slightly distal to midlength and bearing blunt longitudinal ridge extending from fixed finger to about midlength of palm, followed by longitudinal row of long setae extending to ventroproximal corner; mesial surface unarmed, but with longitudinal row of long setae proximal to mesial dactylar condyle. Fixed finger distinctly shorter than dactylus, slightly deflexed, tapering to acute tip, occlusal margin with 5 triangular, subacute teeth. Dactylus terminating in corneous tip preceded on occlusal margin by thin, bluntly toothed edge, no conspicuous tooth; extensor margin rounded, non-carinate; lateral surface with 2 longitudinal rows of simple setae along midline, becoming contiguous distally; mesial surface with 2 longitudinal rows of simple setae along extensor margin and with median row of 10 – 13 small, rounded tubercles diminishing distally (Fig. 4 F). Second pereopod (Fig. 5 A) reaching base of dactylus of first pereopod; merus with 1 subdistal spine on dorsal margin, ventral margin unarmed; carpus spineless. Third pereopod (Fig. 5 B) ischium spineless; merus with row of 5 small spines on proximal half of ventral margin; lateral surface with short, vertical multidenticulate ridges on ventral half. Fourth pereopod (Fig. 5 C) with spineless merus. Fifth pereopod without distinguishing features. Gills of type C (Ngoc-Ho 1981; lamellae slender, deeply quadriserial, cf. McLaughlin & de Saint Laurent 1998). Uropod (Fig. 3 E) with protopod having tiny spine on posterior margin above base of endopod. Endopod subtrapezoidal with somewhat produced, subacute posterolateral angle; lateral margin gently sinuous; posterior margin faintly sinuous, with minute denticles or spinules. Exopod subtrapezoidal; lateral margin weakly sinuous proximally, with small knob-like tubercle proximally; posterior margin broadly convex, with row of minute denticles or spinules.	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFCFFFC8FF33B00EDA9799F1.taxon	distribution	Distribution. Known with certainty from Hong Kong and Ryukyu Islands; intertidal to 10 m deep (Stimpson 1860; Sakai & Takeda 1995; Itani 2004; Saigusa et al. 2018; this study).	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFCFFFC8FF33B00EDA9799F1.taxon	biology_ecology	Habitat. The present specimens were all collected from soft sediments, although sometimes mixed with gravels, where the animals burrowed.	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFCFFFC8FF33B00EDA9799F1.taxon	discussion	Remarks. Upogebia carinicauda was originally described based on material from Hong Kong (as Gebia), although Stimpson (1860) did not specify how many specimens he had at his disposal. As Dworschak & Anker (2020) noted, the type material is no longer extant, most probably destroyed during the Great Chicago Fire in 1871 (Evans 1967). Stimpson’s (1860) original description is quite brief, but mentions the following diagnostic characters: (1) the palm of the first pereopod is armed with a spine on the ventral margin proximal to the base of the fixed finger; (2) the occlusal margin of the fixed finger is denticulate; (3) the telson is provided with an elevated transverse carina near the proximal margin on the dorsal surface; (4) the uropodal rami are armed with spinules on each posterior margin. In addition, Stimpson (1860) pointed the affinity of his new species to U. major (De Haan, 1841) (as Gebia majori), which has subchelate first pereopod (e. g., Sakai 1968). In the diagnostic aspect, the present five specimens from Amami-ohshima and Okinawa Islands closely match U. carinicauda (also see Sakai & Takeda 1995). Ngoc-Ho (1979) and Sakai (1982) re-examined materials previously identified by other workers with U. carinicauda, including paratypes of U. kempi (e. g., Strahl 1862; Miers 1884; De Man 1928; Sankolli 1972), in an effort to clarify the specific identity of U. carinicauda. As a result, it has been believed that this species is widely distributed throughout the Indo-West Pacific. Some previous studies have indicated that this species shows substantial individual variation (e. g., De Man 1928; Ngoc-Ho 1979, 2008; Sakai 1982; Dworschak & Anker 2022). Nevertheless, our investigation reveals that multiple species have been confounded under Upogebia carinicauda, raising questions about previous species identifications (see above synonymy), although thorough review of references is deferred due to difficulties in accessing the voucher specimens. Future study utilizing genetic data will aid in refining the specific identity of populations in different regions. Upogebia (Upogebia) carinicauda var. gracilipes was described by De Man (1927) based on a small female specimen from Buka Island, Solomon Islands. De Man (1927) distinguished his new taxon from the nominotypical U. carinicauda mainly by the slender first pereopod. Sakai (1982) re-examined the holotype of De Man’s (1927) taxon and concluded that it was a junior subjective synonym of U. carinicauda. Considering De Man’s (1927) description, it is unlikely that U. carinicauda var. gracilipes and the two other species revalidated in this study are conspecific. Differentiating characters among U. carinicauda, U. foresti and U. rupicola are summarized in Table 4 and discussed in detail below under account of respective species. The present five specimens all have gonopores on the coxae of the third and fifth pereopods, while there are no first pair of pleopods, referred to as intersex following Ngoc-Ho (2001).	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFC6FFD0FF33B69DD88499FD.taxon	vernacular_names	[New Japanese name: Toge-nashi-minami-ana-jyako]	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFC6FFD0FF33B69DD88499FD.taxon	description	(Figs. 6 – 8)	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFC6FFD0FF33B69DD88499FD.taxon	materials_examined	Material examined. CBM-ZC 18136, 1 intersex (cl 7.4 mm; DNA voucher 1483), Futami, Ohura Bay, Okinawa Island, intertidal sand flat, inhabiting in burrows on dead coral block buried in sand sediment, 22 June 2009, coll. T. Komai & M. Osawa; CBM-ZC 18137, 1 female (cl 6.9 mm; DNA voucher 1493), same data; CBM-ZC 18138, 4 intersex (cl 3.9 – 5.3 mm), same data.	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFC6FFD0FF33B69DD88499FD.taxon	description	Description. Rostrum (Fig. 6 A, B) relatively short, overreaching distal corneal margins by 0.2 – 0.3 length, subtriangular, nearly as broad as long at base, directed forward, straight in lateral view; dorsolateral margins with 2 pairs of strong, obliquely erect spines of nearly equal size; ventral surface unarmed. Carapace (Fig. 6 A, B) with posteriorly divergent gastric lateral ridges not produced anteriorly, each ridge bearing about 10 small spines or tubercles reducing in size and sharpness posteriorly. Shoulder lateral to cervical groove not ornamented; linea thalassinica continuing to posterior carapace margin. Postocular spine simple. Epistomial projection (Fig. 6 A) rather broad in lateral view, bearing 1 spinule on either side. Pleonal sternites unarmed. Six pleomere posterior margin (Fig. 6 C) smooth, without denticles or spinules. Telson (Fig. 6 C) trapezoidal, bearing prominent transverse proximal ridge confluent with longitudinal ridge at each side. Ocular peduncle (Fig. 6 A) stout, unarmed distomesially; cornea slightly narrower than proximal diameter of ocular peduncle. Antennular peduncle (Fig. 6 A) reaching to midlength of fifth article of antennal peduncle; proximal 2 articles together subequal in length to third article, first article with tiny spine at ventromesial distal angle. Antennal peduncle (Fig. 6 A) extending beyond tip of rostrum by half-length of fourth article; all but second article spineless, second article with small ventromesial distal spine; scaphocerite moderate, suboval with pointed distolateral angle. Third maxilliped without epipod. First pereopod (Fig. 7 A – E) moderately stout. Coxa unarmed on distomesial margin. Ischium bearing 2 spinules on ventral margin laterally. Merus with row of about 10 spinules or denticles markedly reducing in size distally on ventral to ventromesial margin; dorsal margin convex, with 1 tiny subdistal spine. Carpus trigonal, with shallow longitudinal groove on lateral surface; flexor distal corner with 1 tiny tubercle and 1 spinule; extensor distal margin armed with 2 or 3 denticles or spinules, sometimes microscopic in size (Fig. 7 D); extensor mesial margin not crested, unarmed or armed with 1 – 4 minute denticles (Fig. 7 D); distomesial margin with 2 unequal spines, upper spine at extensor distal angle moderately strong, lower spine much smaller (Fig. 7 C). Carpus-chela articulation somewhat twisted. Palm about 2.5 times as long as wide; dorsal surface rounded, with longitudinal row of long setae, but without row of spines or tubercles (Fig. 7 C); lateral dactylar condyle well marked; lateral surface with oblique line of plumose setae extending from mid-proximal margin to slightly beyond midlength on ventral surface; mesial dactylar condyle unarmed (Fig. 7 E); mesial surface with few spinules or denticles proximodorsally, followed by proximal vertical ridge; ventral surface bearing blunt longitudinal ridge extending from fixed finger to about midlength of palm, followed by longitudinal row of long setae extending to ventroproximal corner; no conspicuous spine on ventral surface. Fixed finger distinctly shorter than dactylus, slightly deflexed, tapering to blunt or acute tip; occlusal margin with 3 – 5 low, obsolescent teeth. Dactylus with calcareous or corneous tip preceded on occlusal margin by thin, proximally bluntly toothed edge, no conspicuous teeth; extensor margin rounded, non-carinate; lateral surface with 2 longitudinal rows of simple setae along midline, becoming contiguous distally; mesial surface with 2 longitudinal rows of simple setae along extensor margin and with median row of about 10 rounded tubercles diminishing in size distally (Fig. 7 E). Second pereopod (Fig. 7 F) reaching base of dactylus of first pereopod; merus with 1 subdistal spine on dorsal margin, ventral margin unarmed; carpus spineless Third pereopod (Fig. 7 G) ischium and merus spineless. Fourth pereopod (Fig. 7 H) with spineless merus. Fifth pereopod without distinguishing features. Gills of type C (Ngoc-Ho 1981; lamellae slender, deeply quadriserial, cf. McLaughlin & de Saint Laurent 1998). Uropod (Fig. 6 E) with protopod having tiny spine on posterior margin above base of endopod. Endopod trapezoidal with rounded posterolateral angle, unarmed on faintly convex posterior margin. Exopod subtrapezoidal; lateral margin weakly sinuous proximally; posterior margin with row of minute denticles, including one at posterolateral angle. Colouration in life. Cephalothorax yellowish brown medially, branchial regions translucent with brown tinge; pleon yellowish brown, telson and uropods translucent; cornea darkly pigmented; first pereopods tan, second to fifth pleopods translucent (Fig. 8).	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFC6FFD0FF33B69DD88499FD.taxon	distribution	Distribution. Known with certainty from Ryukyu Islands, southwestern Japan, and Indonesia; intertidal.	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFC6FFD0FF33B69DD88499FD.taxon	biology_ecology	Habitat. The specimens examined in this study were found to inhabit burrows in a dead coral rock buried in sand sediment.	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFC6FFD0FF33B69DD88499FD.taxon	discussion	Remarks. Upogebia foresti has been placed under the synonym of U. carinicauda (cf. Ngoc-Ho 2008; Dworschak & Anker 2022; WoRMS 2026; DecaNet 2026). Sakai & Türkay (2014) treated U. foresti as a distinct species, but the authors did not comment why they regard it as a valid species. The present specimens, including two genetically differentiated from material identified with U. carinicauda, match morphologically with U. foresti in the following diagnostic features (cf. Ngoc-Ho 1989: 870 – 871, fig. 3): (1) the relatively small mesiodistal spines of the first pereopod carpus (Fig. 7 C, D); (2) the absence of a distal spine on the mesial dactylar condyle and the ventral spine proximal to the base of the fixed finger of the first pereopod palm (Fig. 7 B, C); (3) poorly developed occlusal armature of the first pereopod dactylus (Fig. 7 E); (4) the absence of ventral tubercles or spinules on the merus of the third pereopod (Fig. 7 G). In addition to those characters already mentioned by Ngoc-Ho (1989) to differentiate U. foresti from U. carinicauda, the shape of the uropodal endopod is different between U. foresti and U. carinicauda: the posterolateral angle of the endopod is rounded in U. foresti (Fig. 6 E), rather than narrowly produced in U. carinicauda (Fig. 3 E). Spinules or denticles on the posterior margins of the uropodal rami seem to be much smaller in U. foresti than in U. carinicauda (Fig. 6 E versus Fig. 3 E). Given the far distant localities between the type material and the present specimens, it is possible that the Okinawan specimens might not be conspecific with the true U. foresti, but considering the high morphological similarities, we believe that it is reasonable to identify the Okinawan specimen as U. foresti under the current circumstances. Differentiation between U. foresti and U. rupicola is discussed under the account of the latter species. Sakai (2006) considered that U. foresti was synonymous with U. kempi, but based on the original description, U. kempi is morphologically closer to U. carinicauda. There is little doubt that U. foresti and U. kempi are not conspecific. The taxonomic status of U. kempi needs reappraisal, although this taxon is treated as a valid species in WoRMS (2026) and DecaNet (2026). Of the six specimens examined, only one specimen is attributed to female (third pereopod coxae each with a gonopore, fifth pereopod coxae without gonopores and first pleopods present). Other specimens are referred to intersex following Ngoc-Ho (2001) because of the possession of gonopores on both third and fifth pereopods while no first pair of pleopods.	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFDAFFD1FF33B69DDD9D9BF9.taxon	materials_examined	Material examined. Holotype. CBM-ZC 8138, male (cl 12.1 mm), Nashiro, Itoman, Okinawa Island, Ryukyu Islands, intertidal, burrow in siltstone, 18 August 2002, coll., Y. Kano et al. Paratypes. CBM-ZC 8139, 3 males (CL 10.9 – 13.1 mm), 3 females (CL 7.7 – 13.8 mm), 1 ovigerous female (CL 13, 8 mm), same data as holotype. Other material. CBM-ZC 9841, 1 young male (cl 4.9 mm), 4 females (cl 9.1 – 14.1 mm; individual of cl mm 12.6 mm DNA voucher), Kitanashiro, Itoman, Okinawa Island, Ryukyu Islands, intertidal, burrowing in sandstone substrate, 13 January 2010, coll. T. Maenosono; CBM-ZC 10448, 1 intersex (cl 5.7 mm), same data as holotype.	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFDAFFD1FF33B69DDD9D9BF9.taxon	description	Description. See Komai (2005: 260 – 266, figs. 1 – 4).	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFDAFFD1FF33B69DDD9D9BF9.taxon	distribution	Distribution. Presently known only from Okinawa Islands, Ryukyu Islands; intertidal (Komai 2005; Saigusa et al. 2018; this study).	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFDAFFD1FF33B69DDD9D9BF9.taxon	biology_ecology	Habitat. All the specimens examined were found to burrow in sandstone or siltstone substrate in intertidal zone.	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
03F54170FFDAFFD1FF33B69DDD9D9BF9.taxon	discussion	Remarks. Upogebia rupicola is distinguishable morphologically from U. carinicauda and U. foresti by the fully chelate first pereopod, of which the fixed finger is sometimes arcuate and the dactylus is armed with conspicuous teeth on the occlusal margin (Komai 2005: fig. 4 A – E). In the latter two species, the fixed finger of the first pereopod is distinctly shorter than the dactylus, making the first pereopod being subchelate; and the dactylus has low or obsolescent tubercles on the occlusal margin. The spines or tubercles on the lateral gastric ridges of the carapace are generally more pronounced in U. rupicola (Komai 2005: fig. 1 A) than in U. carinicauda (Fig. 3 A) and U. foresti (Fig. 6 A). The first pereopod palm is armed with a row of small but conspicuous spines on the dorsal surface mesially over the almost entire length in U. rupicola (Komai 2005: fig. 4 A, D), whereas such spines are absent in U. foresti (Fig. 7 C). In U. carinicauda, the first pereopod palm has only a few small spines mesiodistally on the dorsal surface, sometimes followed by a row of minute tubercles (Fig. 4 A, C, E). The presence of a strong ventral spine on the first pereopod palm, located proximal to the base of the fixed finger, and the narrowly produced posterolateral angle of the uropodal exopod, are also useful to distinguish U. rupicola and U. carinicauda from U. foresti. In addition, U. rupicola inhabits burrows constructed in sedimentary rocks in intertidal zone (Komai 2005; Saigusa et al. 2018; this study), while U. carinicauda inhabits soft sediments, sometimes mixed with gravels at intertidal to subtidal depths (this study). The present specimens of U. foresti were found to inhabit burrows in coral rocks buried in sand in tidal flat, but it is still unclear if such habitat is specific to U. foresti because there is still little information available. As stated above, the treatment of this species in the literature has not been consistent (Sakai 2006; Ngoc-Ho 2008; Sakai & Türkay 2014; Sagusa et al. 2018; Komai 2020; WoRMS 2026; DecaNet 2026).	en	Komai, Tomoyuki, Fujita, Yoshihisa (2026): Revalidation of the two upogebiid mud shrimp species, Upogebia foresti Ngoc-Ho, 1989 and Upogebia rupicola Komai, 2005, removed from the synonymy of Upogebia carinicauda (Stimpson, 1860) (Decapoda: Gebiidea). Zootaxa 5763 (3): 349-370, DOI: 10.11646/zootaxa.5763.3.3, URL: https://doi.org/10.11646/zootaxa.5763.3.3
