taxonID	type	description	language	source
03F187F55606FFE8FF151A693178FBB2.taxon	description	(Fig. 2)	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
03F187F55606FFE8FF151A693178FBB2.taxon	materials_examined	Type locality. “ Le torrent de Ning-kouo-hien. ” Johnson (1973) and Graf & Cummings (2017) placed this locality in Anhui Province in the Yangtze and Huai River basins in eastern People’s Republic of China. Type materials. Syntypes: MNHN 3425, MNHN 3427; SMF 3597 (Graf & Cummings, 2017); USNM 126480 [2 specimens] (Smithsonian Institution Database, 14 August 2017) [listed as paratypes by Johnson, 1973]. Other materials. NZMC FM 01681 (He & Zhuang, 2013: 89).	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
03F187F55606FFE8FF151A693178FBB2.taxon	discussion	Discussion. There are no known preserved specimens available for anatomy or molecular analyses for P. biesiana. It is only known from five dry shell specimens. The specimen NZMC FM 01681 from Sichuan province, People’s Republic of China figured by He & Zhuang (2013) is identified as P. biesiana, but differs from the illustrated syntypes (Fig. 2) in having two short lateral teeth in the left valve. This specimen has greater lateral tooth development than exhibited by the syntype specimens and is from much farther west in China. It appears to be morphologically between P. biesiana and P. banggiangensis new species, which has well developed, long lateral teeth. This specimen may represent another new species in Pseudobaphia, but more specimens are required to answer this question. Historically, Haas (1969 a, b) placed Pseudobaphia in the Quadrulinae, but modern molecular analyses restrict this subfamily to North America and it does not include any Asian taxa (Lopes-Lima et al., 2017). The phylogenetic position of Pseudobaphia is assumed to be in Unionidae, but assignment to subfamily or tribe is not now possible and is currently listed as Unionidae (incertae sedis) (Graf & Cummings, 2007; Lopes-Lima et al., 2017; Zieritz et al., 2017). Live specimens of this species are required to answer the question of Pseudobaphia ’ s phylogenetic position.	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
03F187F55606FFE8FF151A693178FBB2.taxon	description	Description. “ Shell large, rather solid, inflated, subrhomboid, somewhat equilateral; beaks very full and high, corrugated; ligament large, brown; posterior ridge more or less double, ending in a biangulation at and below the median line, the region above it obliquely truncate; epidermis fuscousolivaceous, slightly rayed when young; surface smooth and shining medially; pseudocardinals strong, stump, slightly roughened, showing behind them numerous nodules; lateral feeble, in old shells almost wanting; anterior scars deep in the hinder portion; posterior scars large; beak cavities deep, compressed; nacre dirty white or flesh-colored. Length 106, height 76, diam. 52 mm. ” Simpson (1914: 1139).	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
03F187F55606FFEDFCB41B893675F972.taxon	description	(Figs. 3, 4, 5, 6, 7)	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
03F187F55606FFEDFCB41B893675F972.taxon	diagnosis	Diagnosis. Pseudobaphia banggiangensis new species is distinguished from other unionid species by the following characters: rather thick shell, inflated, slightly rectangular to oval shell outline, well developed pseudocardinal teeth with nodules extending posteriorly, but not over whole of interdentum, well developed lateral teeth, periostracum smooth, posterior ridge smooth, umbo sculpture consisting of a series of parallel bars, often eroded. Soft anatomy is unknown.	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
03F187F55606FFEDFCB41B893675F972.taxon	description	Description. Shells examined reach approximately 70 mm in total length, shell shape slight rectangular to oval in outline, inflated, anterior shell margin evenly rounded, dorsal shell margin nearly straight, ventral margin broadly rounded, posterior margin rather straight or almost squared off, posterior ridge rounded, posterior slope smooth, umbo area inflated, umbo sculpture a series of parallel bars in one specimen with an early bar breaking up into three elongate pustules followed by parallel bars continuing down onto the disk, periostracum reddish brown to dark brown, shell surface smooth lacking any sculpture. Pseudocardinal teeth in right valve with one peg-like, striated pseudocardinal tooth anterior of the umbo, one long, straight lateral tooth, left valve with two striated or sculptured large pseudocardinal teeth extending posteriorly into the interdental area under the umbo and two straight well-developed lateral teeth. Anterior adductor muscle scar deep, smooth and impressed, pedal protractor muscle scar separate, anterior pedal retractor muscle scar united with the anterior adductor muscle scar, posterior adductor muscle scar very faint, pallial line impressed anteriorly, fading posteriorly, umbo cavity open, rather deep, nacre color white becoming bluish iridescent toward posterior margin.	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
03F187F55606FFEDFCB41B893675F972.taxon	materials_examined	Holotype. Institute of Ecology and Biological Resources (IEBR), Vietnam Academy of Science and Technology, Hanoi. IEBR-MO 1, Fig. 3. No collector known. Paratypes. NCSM 102866, 2 unpaired valves; Biology Department, Vietnam National University, University of Science, Hanoi, MB- 015 K 60, 10 unpaired valves. No collector known (Figs. 4, 5, 6) (Table 1). Type locality. This species is known only from the B ằng River, Cao B ằng Province, Vietnam. The B ằng River is a headwater tributary of the Zhu Jiang (Pearl River) draining into the South China Sea in southeast China. The specimens were collected in February 1971. No collector was recorded (Figs. 3, 4, 5, 6). Comparison with similar species. Pseudobaphia banggiangensis new species does not resemble any other species found in Vietnam with an oval shell shape, very inflated shell and a smooth shell surface with a dark periostracum. Sinanodonta jourdyi has a thin shell and lacks any hinge teeth. Cristaria plicata is thinner shelled, often with posterior dorsal plications and lacks pseudocardinal teeth and has a long thin, lateral tooth. Aculamprotula, Gibbosula, and Lamprotula species are thick shelled, but not as inflated and typically have some plications or pustules on the surface with well-developed hinge teeth. Pseudobaphia banggiangensis new species was originally identified as Protunio messageri (Fig. 1), but that species is rectangular, and has surface sculpture, which is lacking in P. banggiangensis new species. This new species resembles the shell shape, inflation, smooth shell and lack of external sculpture and well developed pseudocardinal teeth with numerous nodules on the hinge plate anterior to the lateral teeth as in Pseudobaphia biesiana (Fig. 2). But, P. banggiangensis new species (Figs. 3, 4, 5) differs by having well developed, long lateral teeth unlike the reduced or feeble lateral teeth in P. biesiana (Fig. 2).	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
03F187F55606FFEDFCB41B893675F972.taxon	distribution	Distribution. This species is known only from the B ằng River, Cao B ằng Province, Vietnam (Fig. 7) (Do et al., in press). Habitat and biology. No notes or information were included with the IEBR or Hanoi University of Science, Museum of Biology specimens. All examined specimens are dry shells and no soft tissues have been preserved. Conservation status. The specimen label stated the date of collection was February 1971 (Fig. 6). This species has not been reported or collected since 1971. During discussions with local farmers and mussel sellers in local markets in Cao B ằng Province, they do not remember seeing this species. We have not found any evidence this species has been collected in the last 46 years. It is either extremely rare, but more likely presumed extirpated in Vietnam, but we lack any information on the rest of the Pearl River basin in China. Other freshwater mussel taxa reported from Cao B ằng Province that are considered at least extirpated from Vietnam include Lamprotula bazini (Heude, 1877) and Lamprotula blaisei (Dautzenberg & Fischer, 1905) (Do et al., in press). Until last year, Gibbosula crassa (Wood, 1815) was considered extirpated in Vietnam until it was rediscovered in a very short reach of the B ằng River, Cao B ằng Province (Bogan & Do, 2016). Extinction of freshwater mussels around the world is increasing (Bogan, 2008; Lydeard et al., 2004; Tedesco et al., 2014) and has been attributed to various causes including: deforestation and effects on rivers, dams and reservoirs, mining, pollution, etc. (e. g., Vaughn & Taylor, 2001; Lydeard et al., 2004; Bogan, 2008; Meyfroidt & Lambin, 2008; Strayer & Dudgeon, 2010).	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
03F187F55606FFEDFCB41B893675F972.taxon	etymology	Etymology. The species is named for the B ằng River in Cao B ằng Province, Vietnam, where the species was collected. Comparative material examined. No additional specimens outside of those in Hanoi were found. Figures of Pseudobaphia biesiana from Haas (1910 – 1920), He & Zhuang (2013) and Graf & Cummings (2017) were compared with the type series of P. banggiangensis new species.	en	Bogan, Arthur E., Do, Van Tu (2018): An overlooked new species of freshwater bivalve from northern Vietnam (Mollusca: Bivalvia: Unionidae). Raffles Bulletin of Zoology 66: 78-86, DOI: 10.5281/zenodo.4504624
