| Page last updatedWed 1 October 2025
 | The Freshwater Mussels (Unionoida) of the World (and other less consequential bivalves)FM(U)otW(aolcb) is the web version of the MUSSEL Project Database. Follow the links to browse the data or use the custom Google search field. Either way, you win! 
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 Bivalvia | Unionoida | Unionoidea | Unionidae | Ambleminae | Popenaiadini | Nephronaias species Nephronaias dysonii (Lea, 1859): specimens2 available nominal species synonyms
 Recent Taxonomic OpinionsNephronaias dysonii — Graf & Cummings (2007), Bogan (2010), Graf & Cummings (2021), Cummings et al. (2025)Nephronaias sajensis — Graf & Cummings (2007), Bogan (2010), Graf & Cummings (2021)
 RangeWidespread from northern Belize, south to Guatemala and Honduras. Map of Georeferenced Specimens
 Belize|  UF_207820
 Aguacate River [Moho River], 6.2 km S Blue Creek Village, Toledo District, Belize 16° 08.9’ N, 89° 00.9’ W
 |  UF_207821
 Aguacate River [Moho River], 6.2 km S Blue Creek Village, Toledo District, Belize 16° 08.9’ N, 89° 00.9’ W
 |  INHS_36540
 Aguacate River, 19 mi WNW Punta Gorda, Toledo, Belize
 |  |  INHS_36541
 Aguacate River, 19 mi WNW Punta Gorda, Toledo, Belize
 |  INHS_27586
 Aguacate River, rm 25, NE Aguacate, Toledo, Belize
 |  INHS_27987
 Aguacate River, rm 25, NE Aguacate, Toledo, Belize
 |  |  FMNH_21860
 Belize, British Honduras
 |  UMMZ_60368
 Belize, British Honduras
 |  UF_184065
 Booths River, just upstream junct. with Rio Bravo, Orange Walk Dist., Belize
 |  |  BMNH_89-12-7-19
 British Honduras
 |  FMNH_120429
 British Honduras
 |  USNM_664687
 British Honduras
 |  |  USNM_664687
 British Honduras
 |  INHS_46386
 Central Belize
 |  UF_243984
 Chan Chich Creek (Rio Bravo), nr. Gallon Jug, nr. Chan Chich Lodge, Orange Walk District, Belize
 |  |  UF_517939
 Chan Chich Creek> Rio Bravo> Bahia de Chetumal Near Chan Chich Lodge near Gallon Jug Orange Walk District, Belize `18oN, ~87oW
 |  UF_207299
 creek, 16.6 km WSW Rancho Dolores, Orange Walk District, Belize 17° 30.5’ N, 88° 43.7’ W
 |  UF_207299
 creek, 16.6 km WSW Rancho Dolores, Orange Walk District, Belize 17° 30.5’ N, 88° 43.7’ W
 |  |  UF_207303
 creek, 16.6 km WSW Rancho Dolores, Orange Walk District, Belize 17° 30.5’ N, 88° 43.7’ W
 |  INHS_46385
 creek, Pueblo Viejo, 38.3 km WNW Punta Gorda, Toledo District, Belize
 |  MCZ_59651
 Gongora River, British Honduras
 |  |  MCZ_59651
 Gongora River, British Honduras
 |  UF_207626
 Hickatee Creek, trib. of Rio Bravo, 5.7 km NE Big Falls Village, Toledo District, Belize 16° 17.7’ N, 88° 52.0’ W
 |  UF_201624
 Indian Creek, at S Hwy, 8.1 km NE Indian Cr. Village, Toledo District, Belize 16° 21.7’ N, 88° 48.0’ W
 |  |  UF_207623
 Indian Creek, at S Hwy, 8.1 km NE Indian Cr. Village, Toledo District, Belize 16° 21.7’ N, 88° 48.0’ W
 |  UF_207624
 Indian Creek, at S Hwy, 8.1 km NE Indian Cr. Village, Toledo District, Belize 16° 21.7’ N, 88° 48.0’ W
 |  INHS_23097
 Macal River, 12 mi S Augustine, Cayo, Belize
 |  |  USNM_382726
 Manatee River, British Honduras
 |  USNM_382726
 Manatee River, British Honduras
 |  UF_207726
 Moho River, 1.3 km W Santa Anna, Toledo District, Belize 16° 05.9’ N, 88° 56.9’ W
 |  |  FMNH_21861
 Punta Gorda, British Honduras
 |  FMNH_21864
 Punta Gorda, British Honduras
 |  FMNH_90080
 Punta Gorda, British Honduras
 |  |  UMMZ_57486
 Punta Gorda, British Honduras
 |  UMMZ_57487
 Punta Gorda, British Honduras
 |  UMMZ_60443
 Punta Gorda, British Honduras
 |  |  UF_207222
 Rio Bravo, Cedar Crossing, 21 km S Rio Bravo Research Station, Orange Walk Dist., Belize 17° 41.4’ N, 89° 02.0’ W
 |  UF_207223
 Rio Bravo, Cedar Crossing, 21 km S Rio Bravo Research Station, Orange Walk Dist., Belize 17° 41.4’ N, 89° 02.0’ W
 |  UF_207283
 Rio Bravo, Sylvesters Camp Orange Walk Dist., Belize 17° 35.5’ N, 89° 05.6’ W
 |  |  UF_207284
 Rio Bravo, Sylvesters Camp Orange Walk Dist., Belize 17° 35.5’ N, 89° 05.6’ W
 |  UF_207284
 Rio Bravo, Sylvesters Camp Orange Walk Dist., Belize 17° 35.5’ N, 89° 05.6’ W
 |  UF_517940B
 Rio Bravo> Bahia de Chetumal Cedar Crossing on Gallon Jug Rd., Rio Bravo Cons. Area Orange Walk District, Belize ~18°N, ~87°W
 |  |  UF_517940
 Rio Bravo> Bahia de Chetumal Cedar Crossing on Gallon Jug Rd., Rio Bravo Cons. Area Orange Walk District, Belize ~18oN, ~87oW
 |  UF_207629
 Rio Grande, Big Falls, Toledo District, Belize 16° 15.3’ N, 88° 53.2’ W
 |  UF_207913
 Rio Grande, Big Falls, Toledo District, Belize 16° 15.3’ N, 88° 53.2’ W
 |  |  UF_207913
 Rio Grande, Big Falls, Toledo District, Belize 16° 15.3’ N, 88° 53.2’ W
 |  USNM_150380
 small stream near Punta Gorda, Belize
 |  USNM_193019
 Yaalback Cr., Cayo Distr., Honduras
 |  |  BMNH_97-7-6-1-4
 Yalbac River, Western District, British Honduras
 | 
 
 Guatemala|  MCZ_MP_271
 Guatemala
 |  NCSM_6244
 North America, Guatemala, Rio Saja (Mullee River Dr.), 4-5 mi W of Esmeralda
 |  ANSP_145239
 Rio Saja, 5 mi W Esmeralda, Guatemala
 |  |  FMNH_68188
 Rio Saja, 5 mi W Esmeralda, Guatemala
 |  UMMZ_108010
 Rio Saja, 5 mi W Esmeralda, Guatemala
 |  MCZ_21169
 Rio Saja, Nicaragua
 |  |  MCZ_45420
 Rio Saja, trib. to Rio Dulce, W of Esmeralda, Guatemala
 |  INHS_21773
 Saja River (trib. to Dulce River) 4 or 5 mi W Esmeralda, Guatemala
 |  MCZ_MP_287
 Saja River (trib. to Dulce River) 4 or 5 mi W Esmeralda, Guatemala
 |  |  ANSP_45419
 Saja River, a trib of the Rio Dulce, Nicaragua
 |  ANSP_45419
 Saja River, a trib of the Rio Dulce, Nicaragua
 |  INHS_21772
 Saja River, Esmeralda, Guatemala
 |  |  ZMB_MP_0508
 Tehuantepec, Coban, Vera Paz, Guatemala
 | 
 
 Honduras|  UF_211977
 2.6 km SW La Brea, Colon Department, Honduras 15° 45’ 39” N, 86° 00’ 08” W
 |  ANSP_129445
 Branch of Chamelecon River, Honduras
 |  MCZ_MP_282
 edge of Ulua River, Carozal, Honduras
 |  |  BMNH_1965173
 Honduras
 |  BMNH_1965173
 Honduras
 |  MCZ_MP_270
 Honduras
 |  |  USNM_215593
 La Ceiba, Honduras
 |  UF_22127
 Quebrada Grande, 8.5 km W San Juan, Atlantida Department, Honduras
 |  UF_194521
 Rio Guayape, 10 km SE Catacamas, Olancho Dept., Honduras 14° 45’ 43” N, 85°, 53’ 07” W
 |  |  UF_194522
 Rio Guayape, 10 km SE Catacamas, Olancho Dept., Honduras 14° 45’ 43” N, 85°, 53’ 07” W
 |  UF_221530
 Rio Guayape, 11 km SSE Catacamas, Olancho Department, Honduras
 |  UF_194524
 Rio Guayape, 9 km ENE Juticalpa, Olancho Dept., Honduras 14° 43’ 11” N, 86°, 08’ 43” W
 |  |  FMNH_29002
 Rio Humuya, Comayagua, Honduras
 |  MCZ_MP_290
 Rio Humuya, Comayagua, Honduras
 |  UF_194241
 Rio Sulaco, branch of Cajon Reservior, Yoro Dept., Honduras 14° 01’ 11’ N, 87° 30’ 19” W
 |  |  UF_194241
 Rio Sulaco, branch of Cajon Reservior, Yoro Dept., Honduras 14° 01’ 11’ N, 87° 30’ 19” W
 |  UF_270354
 Rio Ulua, Honduras
 |  UF_221378
 small creek, Icoteas, ca. 17 km E Limon on road to Iriona, Colon Department, Honduras
 |  |  UF_221378
 small creek, Icoteas, ca. 17 km E Limon on road to Iriona, Colon Department, Honduras
 |  UF_221379
 small creek, Icoteas, ca. 17 km E Limon on road to Iriona, Colon Department, Honduras
 |  HMC_1861_01
 unknown river> Caribbean Sea no specific site given, Honduras
 |  |  HMC_1861_02
 unknown river> Caribbean Sea no specific site given, Honduras
 | 
 BMNH_1965174. Honduras 
 unknown |