Brachyhypopomus brevirostris (Steindachner, 1868)

Crampton, William G. R., Santana, Carlos D. de, Waddell, Joseph C. & Lovejoy, Nathan R., 2016, A taxonomic revision of the Neotropical electric fish genus Brachyhypopomus (Ostariophysi: Gymnotiformes: Hypopomidae), with descriptions of 15 new species, Neotropical Ichthyology (e 150146) 14 (4), pp. 639-790 : 692-697

Brachyhypopomus brevirostris (Steindachner, 1868)

( Figs. 1e , 17 ; Tables 2-5, 10)

Rhamphichthys brevirostris Steindachner, 1868b: 177 (original description, no locality given). - Steindachner, 1868a: 254, pl. 2, fig. 2 (redescription, Guaporè [rio Guaporé, Amazonas dr.]).

Rhamphichthys (Brachyrhamphichthys) brevirostris . - Günther, 1870: 6 ( Brazil, rio Guaporé, catalog of fishes in British Museum). - Steindachner, 1880: 89 ( Brazil, rio Guaporé and rio Amazonas nr. Santarém, catalog of fishes).

Brachyrhamphichthys brevirostris . - Eigenmann & Eigenmann, 1891: 62 ( Brazil, rio Guaporé, Santarém, catalog of South American fishes).- Eigenmann, 1894: 625 ( Brazil, Itaituba [lower Tapajós], listing of collections by Frederick C. Hartt).

Hypopomus brevirostris . -Eigenmann & Ward, 1905: 170 (Amazon and tributaries, Paraguay, catalog of gymnotiforms). -von Ihering, 1907: 281 ( Venezuela, lower Amazon, Guaporé, and Paraguay, catalog of Brazilian fishes). - Eigenmann, 1910: 449 ( Guyana to Paraguay, catalog of freshwater fishes). - Eigenmann, 1912: 433 ( Guyana, multiple locations, catalog of freshwater fishes). - Ellis, 1913: 134: fig. 7, head shape; 189, fig. 32, anatomy of swim bladders (lists distribution as Paraguay, lower Tapajós, lower Amazon, Uruguay basin, Rio Grande do Sul, Brazil, and Guyana [records in Rio Grande do Sul and middle or lower Paraguay basin likely refer to B. gauderio , B. bombilla , or B. draco ], gymnotiform diversity and anatomy). -Meek & Hilderbrand, 1916: 310 (“south to the rio Plata” from NW South America [records in Panama refer to B. occidentalis ]). - Eigenmann, 1922: 174 (“south to Paraguay ” from NW South America [records in Panama refer to B. occidentalis ], catalog of fishes in NW South America). - Schindler, 1937: 19, fig. 3, outline of head based on original description; fig, 4, figs. 5-11, outline of heads of syntypes, table with morphometric analysis of syntypes [including designation of lectotype, “Typus”, and paralectotype, “Co-typus”, specimens], discussion of additional specimens of Brachyhypopomus from Paraguay). -Eigenmann & Allen, 1942: 314 (Guianas, Paraguay, Peru at Iquitos and Yurimaguas, listing of gymnotiforms). - Schultz, 1944: 40 (diagnosis against by key and morphological data, in description of B. beebei ). - Fowler, 1945: 179 ( Peru at Iquitos and Yurimaguas, Guianas, Brazil, and Paraguay, listing of congeners). -Schultz: 1949, 65 (key to the Hypopomidae ]. -Heiligenberg & Bastian: 1980: 197, fig. 1, black and white photograph ( Brazil, Amazonas, rio Negro, EOD diversity in sympatric gymnotiforms). -Ortega & Vari, 1986: 13 ( Peru, listing of members of genus). -Kawasaki & Heiligenberg, 1989: 732, fig.1A, black and white photograph of male and female (EODs and communication).

Hypopomus artedi . -Hopkins & Heiligenberg, 1978: 132, fig. 10, black and white photograph ( Suriname, EOD evolution in sympatric gymnotiforms).

Brachyhypopomus brevirostris . -Mago-Leccia, 1994: 48, 168, fig. 68, reproduction of plate 2, fig. 2 from Steindachner, 1868a (listing of Brachyhypopomus ). - Planquette et al., 1996: 396, color photograph of live individual (French Guiana, listing of Brachyhypopomus ). - Crampton, 1996a: 77, table 6.1.a, species list; 79, fig. 6.1 inset 27-29, color photographs; 85, fig. 6.2; 88, fig. 6.3; 92-94, figs. 6.4a, 6.5; 97, fig. 6.7; 191, fig. 11.2; 193, fig. 11.3, EOD data; 110, table 7.5, 113, table 7.7, 115, fig. 7.1, habitats; 136, table 8.2a,b, diet; 151-160, figs. 9.2-9.3, table 9.1a,b, hypoxia tolerance; 165-169, table 10.1, reproductive biology ( Brazil, central Amazon, ecology and signal diversity). -Alves-Gomes, 1997: 523 ( Brazil, Roraima, listing of gymnotiforms). - Sullivan, 1997: 86 (redescription). - Crampton, 1998a: 821, table 4, 834, fig. 9, drawing of adult specimen, with EOD; 837, fig. 10, drawing of caudal filament of male and female ( Brazil, Amazonas, species and EOD diversity). - Crampton, 1998b: 314, table 2, list of Brachyhypopomus ( Brazil, Amazonas, hypoxia tolerance). - Crampton, 1999: 17 ( Brazil, Amazonas, Mamirauá Reserve, listing of species). -Albert & Crampton, 2003: 494 ( Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, Suriname, Venezuela, catalog of hypopomids). - Goulding et al., 2003: 177, center photograph, live individual ( Peru, upper río Madre de Dios, photographic album of fishes). -Maldonado-Ocampo, 2004: table 1 ( Colombia, Orinoco dr. and Meta dr., listing of Brachyhypopomus ). - Crampton & Albert, 2006: 672, fig. 23.8, position in phylogenetic tree; 681, notes on EODs (gymnotiform species and EOD diversity). - Galvis et al., 2006: 212, illustration of head and body; 529, plate 104a, photograph of live specimen ( Colombia, Amazonas, catalog of fishes). - Ferreira et al., 2007: 164, center left photograph, live specimen ( Brazil, Roraima, rio Branco, photographic album of fishes]. - Vari et al., 2009: 46 (Guiana Shield, catalog of fishes). -Crampton, 2011: 176, table 10.2, species list; 179, figs. 10.2-10.3, phylogeny, geographical and ecological distributions (gymnotiform biology). -Mol: 2012, 596 ( Suriname, catalog of fishes). -de Queiroz et al., 2013: 545 ( Brazil, rio Madeira, lago Cuniã, listing of fish).- Carvalho: 2013, 181-185, figs. 41-43, position in phylogeny (phylogenetic systematics of Rhamphichthyoidea ). -Crampton & Ribeiro, 2013: 236, color photograph ( Brazil, rio Madeira, listing of hypopomids). - Tagliacollo et al., 2016: 28, fig. 5 (phylogeny of Gymnotiformes ). - Crampton et al., 2016: 1-66, table 1, 3-4, figs. 1-7, 9, 14, 16, 18-20 (phylogeny, biogeography and ecology of Brachyhypopomus ).

Diagnosis. Brachyhypopomus brevirostris is diagnosed from congeners by the following combination of characters: anal-fin rays 226-293, vs. 143-225 in all congeners except B. beebei , B. bennetti , B. bullocki , B. diazi , B. occidentalis , B. palenque , and B. walteri ; bilateral columns of electrocytes at the anal-fin terminus 3, vs. 4-6 in B. bennetti , B. diazi , B. occidentalis (except some populations in Colombia and Venezuela, see redescription of B. occidentalis ), and B. palenque ; pale stripe along middorsal region of body absent, vs. prominent pale uninterrupted middorsal stripe from occipital region to base of caudal filament present in B. beebei ; precaudal vertebrae 18-21, vs. 15-17 in B. bullocki ; distinct dark suborbital stripe absent, vs. present in B. walteri .

Description. Head and body shape, and pigmentation illustrated in Figs. 1e and 17 . Meristic and morphometric data for examined specimens presented in Tables 2-5 and 10. Body shallow to moderate in depth. Head short to moderate in length and shallow to moderate in depth. Dorsal profile of head straight to slightly convex from occiput to snout, ventral profile of head approximately straight between operculum and snout. Snout rounded. Eye moderate to large in size. Upper jaw with moderate sigmoidal angle between premaxillary and maxillary portions in lateral view. No accessory electric organ over operculum. Gill filaments on first gill arch 40-63 (median 55, n = 38). Pectoral fin narrow to broad in width, pectoral-fin rays 15-20 (mode of 17 in populations from upper Madeira (Guaporé), Orinoco, and upper Paraguay; mode of 18 in a population from central Amazon). Precaudal vertebrae 18-21 (mode of 19 in populations from upper Madeira, central Amazon, and upper Paraguay; mode of 20 in a population from Orinoco), including 1-2 transitional vertebrae. Anal-fin origin slightly (<0.25 HL distance) anterior or posterior to, or near, tip of pectoral fin. Anal-fin rays 226-293; range and median values of all examined populations are similar. Dorsal rami of recurrent branch of anterior lateral line nerve visible in most juvenile and some lightly-pigmented adults; mostly in anterior third of body. Middorsal region of body scaled. Rows of scales above lateral line 7-9 (mode 8). Lateral line continuous. Epidermal canals sparse and in some specimens more or less absent; when present located only in posterior two thirds of body. Isolated short sections of depigmented canals midway between the lateral line and dorsal midline in middle third of the body. Sparse crisscrossing epidermal canals close to and either side, of but mostly dorsal to lateral line in posterior third of body, merging near anal-fin terminus with canals midway between the lateral line and dorsal midline. Three bilateral horizontal columns of electrocytes at anal-fin terminus, and at a mid-point between anal-fin terminus and tip of caudal filament in immature, mature female, and mature male specimens. Extreme tip of caudal filament free of electrocytes. Caudal filament moderate in length to long.

Coloration. ( Figs. 1e , 17 ). Background tan to light brown. Dorsal region without prominent depigmented pale stripe extending along midline from occipital region to base of caudal filament. Prominent wide brown saddles, which extend to dark bands that traverse flank, often exhibiting a misalignment in their continuation at lateral line. Dark bands become fainter ventrally, breaking up into indistinct marks over anal-fin pterygiophores. Indistinct dark markings often present in pale interband area. Contrast between dark bands and saddles and background is typically greater in juveniles but varies among populations. Some large adults become very dark and bands and saddles become indistinct. Caudal filament darker than body, especially dorsally, ventrally, and near tip; with irregular bands along entire length; darkened tip of caudal filament resembles root tips of water hyacinths when viewed underwater. Head with evenly scattered dark chromatophores, darker dorsally. Eye without prominent suborbital patch, or stripe, of chromatophores/subcutaneous pigmentation. Pectoral and anal-fin membranes hyaline. Pectoral-fin rays hyaline with light scattering of brown chromatophores. Anal-fin rays with scattered or uniform dark pigmentation; darker in posterior half of fin. Color in live specimens similar to preserved ones, with opercular region usually rosy due to underlying gills.

among populations of B. brevirostris in the upper Madeira, central Amazon, Orinoco, and upper Paraguay drainages. These observations, in combination with molecular data ( Crampton et al., 2016), support the hypothesis that all populations we have assigned to B. brevirostris are members of a single geographically widespread species, which is morphologically and genetically distinct from all congeners (although we were unable to obtain specimens for genetic analyses from the Paraguay basin).

Size. Moderate to large adult size, largest specimen examined 461 mm TL, 210 mm LEA (n = 1701). No congener reaches greater total length. Largest male specimen examined 461 mm TL, 210 mm LEA (n = 39). Largest female specimen examined 315 mm TL, 230 mm LEA (n = 84).

Sexual dimorphism. Breeding male specimens develop extremely elongated caudal filaments in comparison to immature individuals and breeding females, and consequently reach considerably greater total lengths ( Figs. 17 c-d), but not lengths as measured to anal-fin terminus. Despite possessing longer caudal filaments, breeding males do not exhibit an elevated number of bilateral horizontal columns or vertical rows of electrocytes. Instead they exhibit clearly enlarged electrocytes relative to immature specimens and females. In breeding males caudal filament tip forms a paddle-like laterally compressed structure, some 15-40 mm in length, often completely free of electrocytes. In some males the posterior portion of the caudal filament is entirely free of electrocytes for as much as 48% of caudal-filament length. Some females exhibit a shorter and only slightly laterally compressed caudal filament tip, without electrocytes in terminal portion for up to 10% of caudal-filament length. No sexual differences in pigmentation.

Geographic distribution. Bolivia, Brazil, Colombia, French Guiana, Guyana, Peru, Suriname, and Venezuela ( Fig. 18 ). Widespread through cis-Andean northern South America, including large areas of the Amazonas and Orinoco drainages, northern portions of the Paraguay drainage, coastal drainages of the Guianas and Amapá state, Brazil, and coastal drainages of Pará state, Brazil. As yet unknown from some major tributaries of the Amazon, including the Juruá, upper Japurá-Caquetá, Napo, and upper Xingu, and many southwestern tributaries of the río Orinoco.

Population variation: We found complete overlap in the range of meristic counts ( Tables 2-5) and morphometric proportions ( Table 10), and observed similar pigmentation Ecological notes. Brachyhypopomus brevirostris is an ecologically cosmopolitan species, and varies from being locally rare to exceptionally abundant in lentic and slow-flowing environments throughout its range (Alves-Gomes, 1997; Crampton, 1996a; 1998a; Crampton & Albert, 2006; Crampton & Ribeiro, 2013; de Queiroz et al., 2013; Hopkins & Heiligenberg, 1978; Mol, 2012). It occurs in seasonally inundated floodplains (in floating rafts of meadows and shallow newly-flooded forests), along the margins of rivers (in emergent and floating vegetation), in ephemeral or perennial swamps (in vegetation or submerged debris), and in terra firme forest and savanna streams (in emergent and submerged vegetation, leaf litter and debris, and in marginal root mats and holes). In the lowland Amazon, B. brevirostris occurs in low-conductivity blackwater and clearwater streams, river margins, and floodplain systems (ca. 5-30 μScm-1), and also high-conductivity whitewater river margins and floodplain systems (ca. 90-250 μScm-1), as well as in waters of intermediate conductivity. Nonetheless, it is most abundant in low-conductivity systems. Brachyhypopomus brevirostris is less tolerant of prolonged hypoxia than congeners from the central Amazon, and is unusual among congeners in not exhibiting air-breathing of any kind ( Crampton, 1998b). Breeding occurs during the rising and high water period in populations from Amazonian floodplain floating macrophytes ( Crampton, 1996a: 165). Stomach contents in populations from the central Amazon comprise aquatic insect larvae, microcrustacea, and other small aquatic invertebrates – with a predominance of Chironomidae larvae ( Crampton, 1996a: 136). Large specimens often consume larger aquatic invertebrates.

Co-occurring congeners: Because of its wide geographical range and occurrence in multiple habitats, B. brevirostris occurs in geographical sympatry and ecological syntopy with multiple congeners: in the Amazonas drainage and coastal drainages of the Guianas – B. batesi , B. beebei , B. belindae , B. benjamini , B. bennetti , B. cunia , B. hamiltoni , B. hendersoni , B. pinnicaudatus , B. regani , B. sullivani , B. verdii , B. walteri ; in the Orinoco drainage – B. beebei , B. bullocki , B. diazi , B. provenzanoi , B. regani , and B. sullivani ; in the Paraguay drainage – B. bombilla , B. draco , B. gauderio , and B. walteri .

Local names. Brazil: sarapó (north), tuvira ( Paraguay drainage); Colombia: cuchillo/cuchillo amarillo (Amazon and Orinoco), cuchilleja macana (Putumayo); French Guiana: poisson couteau (French) and multiple creole/ Amerindian names, see Planquette et al. (1996); Peru: macana; Suriname: saprapi; Venezuela: cuchillo.

Remarks. Comments on the type series: In the original brief description, Steindachner (1868b) did not mention specimens, and in the redescription (1868a) he only referred to “several small specimens 2”11’’’ – 7½” long”. The type series consequently consists of several syntypes. Schindler (1937) recognized eight specimens in the NMW as syntypes and designated one of them as (NMW 65040) as “Typus”, consequently a lectotype under the International Code of Zoological Nomenclature, Article 74.5. Schindler considered it to be identical with the specimen on plate 2, fig. 2 in Steindachner (1868a).

Comments on erroneous geographical references: Prior to, and even for several decades after Regan’s (1914) description of B. occidentalis (the only species of Brachyhypopomus to occur in trans-Andean Colombia, Panama, and Costa Rica), the name B. brevirostris was repeated in reference to material collected from Trans-Andean Panama, and Colombia ( Eigenmann, 1922; Eigenmann & Allen, 1942; Eigenmann & Eigenmann, 1891; Eigenmann & Fisher, 1914; Eigenmann & Ward, 1905; Fowler, 1945; Meek & Hildebrand, 1916; Steindachner, 1880). Several reports prior to ca. 1945 list B. brevirostris as occurring in “ Paraguay ” although it is unclear whether the country or river is referenced; although present in the upper Paraguay basin of Brazil, B. brevirostris has not yet been collected in Paraguay.

Material examined. 1,787 specimens. Bolivia / Brazil frontier. NMW 65038, 1, 183 mm, 152 mm LEA (paralectotype) corresponds in size to “Co-typus” specimen from first column of table 2 in Schindler (1937), rio Guaporé, affl. rio Mamoré, affl. rio Madeira, Amazonas dr., no coordinates, J. Natterer. NMW 65040, 1, 164 mm TL, 123 mm LEA (lectotype), collected with NMW 65038. Bolivia. Beni (localities from rio Madeira dr., Amazonas dr.). AMNH 40086 (part), 1, 202 mm, rio Baures, 2 km above mouth, affl. río Guaporé, affl. río Mamoré, 12°30′32″S, 064°16′46″W. CBF 10259, 1, male, 234 mm, UMSS 07033, 1, immature, 160 mm, stream at km 43 on Riberalta-Guayaramerín rd., affl. río Beni, 11°00′30.2″S, 065°39′49.4″W. UMMZ 204512, 1, 131 mm, 9 km SE Costa Marquez (Brazil), río Iténez (rio Guaporé), affl. río Mamoré, ca. 12°30′42″S, 64°10′18″W. UMMZ 204743, 2, 92-167 mm, 6 km SW Costa Marques, río Iténez at mouth of río Baures, affl. río Mamoré, 12°31′S, 064°19′W. UMMZ 205163, 3, 155-167 mm, Backwater of río Iténez, 10km SE Costa Marques, affl. río Mamoré, 12°33′00″S, 064°12′24″W. UMMZ 246440, 1, 170 mm, río Baures (río Blanco), ca. 500 m above mouth on left bank río Iténez, affl. río Mamoré, 12°31′06″S, 064°19′00″W. UMSS 07024, 1, immature, 229 mm, stream at Bocerón, Riberalta - Guayaramerín rd., affl. río Beni, 11°02′50″S, 065°50′07″W. Brazil. Amazonas (localities are from the Amazonas dr.; localities listed from Mamirauá Reserve [Reserva de Desenvolvimento Sustentável Mamirauá] are in rio Solimões-Japurá floodplain, mun. Alvarães). BMNH 1985.6.22.51, 1, 270 mm, rio Tarumazinho [rio Tarumã Mirim], affl. rio Negro, 02°54′S, 060°13′W. BMNH 1998.3.12.133-141, 9, immature, BMNH 1998.3.12.145-156, 12, immature, 2 measured, 200-220 mm, IDSM 444, 7, 90-214 mm, MCP 44605, 1, male ( CS), 374 mm, MCP 44759, 17 (2 CS), 48-243 mm, MCP 45258, 3, female, 210-264 mm, mun. Tefé, Ressaca do Cachorro, lago Tefé, rio Tefé, 03°19′50″S, 64°42′15″W. BMNH 1998.3.12.142-144, 3, immature, BMNH 1998.3.12.157, 1, male, mun. Tefé, Cabeceira do lago Tefé, rio Tefé, ca. 03°34′S, 64°58′W. BMNH 1998.3.12.158, 1, 225 mm, MCP 45332, 1, female, 260 mm, Igarapé Baré, lago Amanã, affl. río Japurá, 02°25′05″S, 64°42′58″W. IDSM 443, 1, 80 mm, MCP 45331, 3 (1 immature, 272 mm, 1 male, 340 mm, 1 unsexed, 223 mm), Mamirauá Reserve, cano do lago Rato, 03º02′41″S, 064º51′26″W. INHS 70542, 1 (part), lago Camaleão, Ilha da Marchantaria, rio Solimões floodplain, 03°14′S, 059°56′W. INHS 71264, 1, 223 mm, lago do Janauari, rio Amazonas floodplain, 03°13′S, 060°00′W. INPA 4388, 2, 128-150 mm, INPA 12265, 1, 200 mm, INPA 19936, 1, 160 mm, INPA 19937, 2, 125-136 mm, Arquipelago das Anavilhanas, rio Negro, 02°41′S, 060°44′W. INPA 8857, 33, km 55 on Manaus-Manacapuru hwy. AM-070, stream, affl. rio Solimões, ca. 03°13′S, 060°26′W. INPA 9947, 19, 127-310 mm, Mamirauá Reserve, lago Caetano, 02º50′58″S, 064º55′42″W. INPA 9948, 3, 290-420 mm, INPA 9949, 3, 218-240 mm, mun. Tefé, Cabeceira do lago Tefé, rio Tefé, 03°34′S, 064°58′W. INPA 15814, 6 (3 immature, 54-145 mm, 1, female, 253 mm, 2 male, 370-461 mm), MCP 44606, 7 (3 immature [2CS], 124-175 mm, 2 female, 233-270 mm, 2 male [1CS], 295-308 mm), mun. Tefé, Cabeceira do lago Tefé, rio Tefé, 03°36′55″S, 064°57′33″W. INPA 15815, 7, immature, 36-108 mm, INPA 18344, 3, immature, 77-78 mm, MCP 45379, 6 (4 immature, 85-132 mm, 1, female, 203 mm, 1 male, 285 mm), MCP 45470, 20, immature, 97-218 mm, mun. Tefé, Ressaca do Socorro, lago Tefé, rio Tefé, 03°18′45″S, 064°41′50″W. INPA 17185, 6, 80-180 mm, lago Campina, rio Purus, 04°55′59″S, 062°56′25″W. INPA 17186, 5, 90-202 mm, Paraná do Seixo, lago Jari, rio Purus, 04°54′41″S, 062°27′ 26″W. INPA 17189, 21, 56-213 mm, lake nr. Sacado da Santa Luzia, rio Purus, 04°42′17″S, 062°22′ 26″W. INPA 18247, 1, female, 238 mm, INPA 18345, 2 (1 female, 276, 1 male, 205), MCP 45386, 1, male, 225 mm, Mamirauá Reserve, lago Araçazinho, 02º59′35″S, 064º51′33″W. INPA 18248, 3 (1 immature, 227 mm, 1, female, 230 mm, 1 male, 216 mm), Mamirauá Reserve, lagoArauaé, 03º02′52″S, 064º50′04″W. INPA 18249, 1 male, 279 mm, MCP 45395, 2 (1 immature, 238 mm, 1 female, 240 mm), Mamirauá Reserve, cano do lago Arauaé, 03º03′54″S, 064º49′04″W. INPA 18250, 1, male, 293 mm, INPA 18251, 1, immature, 222 mm, MCP 45260, 2, female, 237-305 mm, Mamirauá Reserve, lago Secretaria, 03º07′12″S, 064°47′49″W. INPA 18252, 1, female, 305 mm, mun. Tefé, Ilha do Martelo, rio Tefé, 03°46′56″S, 064°59′39″W. INPA 18342, 1, female, 150 mm, INPA 18346, 1, female, 192 mm, Mamirauá Reserve, lago Periquito Comprido, 03º04′57″S, 064°46′42″W. INPA 18343, 1, female, 227 mm, mun. Tefé, Cabeceira do lago Tefé, rio Tefé, 03°38′01″S, 064°57′59″W. INPA 18347, 12 (9 female, 180-293 mm, 3 male, 175-220 mm), mun. Tefé, lago Caiambé, rio Caiambé, 03º35′34″S, 064º26′36″W. INPA 19934, 1, 155 mm, igarapé de Duas Bocas, Paraná do Jari, rio Purus, 04°55′33″S, 062°21′58″W. MCP 33367, 1, 208 mm, MCP 45362, 1, female, 188 mm, Mamirauá Reserve, cano do lago Sapucaia, 03º04′07″S, 064°48′32″W. MCP 44758, 9 (1 immature [CS], 257 mm, 4 female [1CS], 242-265 mm, 4 male, 250-395 mm), MCP 45262, 1, male, 366 mm, MCP 45323, 25 (1 immature, 259 mm, 19 female, 138-258 mm, 5 male, 208-311 mm), Mamirauá Reserve, Ressaca da Vila Alencar, 03º07′41″S, 064°48′04″W. MCP 45259, 1, female, 235 mm, Mamirauá Reserve, lago Matá Matá, 03º06′17″S, 064°47′17″W. MCP 45261, 1, female, 228 mm, Mamirauá Reserve, lago Promessa, 03º04′29″S, 064°47′02″W. MCP 45263, 2 (1 female, 269 mm, 1 male, 397 mm), MCP 45472, 1, immature, 150 mm, mun. Tefé, rio Tefé, 03°41′23″S, 064°59′08″W. MCP 45317, 7 (6 immature, 86-127 mm, 1 female, 315 mm), MCP 46930, 2, immature (2 CS), 110-178 mm, MCP 46935, 1 post-larval ( CS), 30 mm, Mamirauá Reserve, cano do lago Mamirauá, 03º03′51″S, 064º51′05″W. MCP 45318, 3 (2 immature, 149-225 mm, 1 male, 265 mm), MCP 46927, 1, immature ( CS), 136 mm, Mamirauá Reserve, lago Bolsinha, 03º03′47″S, 064º50′03″W. MCP 45319, 1, immature, 161 mm, MCP 45404, 1, female, 279 mm, Mamirauá Reserve, lago Pagão, 03º02′32″S, 064º50′25″W. MCP 45322, 2 (1 immature, 111 mm, 1 male, 156 mm), MCP 45378, 2, female, 170-215 mm, mun. Tefé, Cabeceira do lago Tefé, rio Tefé, 03°35′41″S, 064°58′05″W. MCP 45326, 2, immature, 103- 175 mm, Mamirauá Reserve, lago Sumaumeirinha I, 02º48′26″S, 065º04′33″W. MCP 45363, 1, female, 275 mm, Mamirauá Reserve, cano do lago Mamirauá, 03º06′40″S, 064°47′52″W. MCP 45396, 2, female, 250-273 mm, Mamirauá Reserve, lago Periquito Redondo, 03º04′50″S, 064°46′35″W. MCP 45402, 1, immature, 100 mm, Mamirauá Reserve, lago Tracajá, 03º05′43″S, 064°46′31″W. MCP 45403, 1, female, 230 mm, Mamirauá Reserve, lago Juruazinho, 03º02′34″S, 064º51′00″W. MCP 45452, 1, immature, 231 mm, mun. Tefé, igarapé Xidarinini, affl. lago Tefé, rio Tefé, 03°22′46″S, 064°41′17″W. MCP 45468, 7, immature, 72-269 mm, mun. Tefé, floodplain lake, Ilha Panamim, rio Solimões, 03°19′29″S, 064°38′37″W. MCZ 9427 (part), 1, 171 mm, mun. Manaus, lago Hyanuary [lago do Janauari], rio Amazonas floodplain, 03°13′S, 060°00′W. MCZ 60046, 1, 84 mm, mun. Parintins, lago Maximo [lago do Maximo], nr. Parintins, rio Amazonas floodplain, ca. 02°40′S, 056°45′W. MCZ 78163 (part), 1, 162 mm, MCZ 78164, 1, 109 mm, mun. Manaus, lago Jacaretinga, nr. Careiro de Várzea, rio Amazonas floodplain, 03°13′00″S, 059°49′41″W. MCZ 165856, 4, 164-196 mm, mun. Manaus, rio Negro nr. lago Alexo [lago do Aleixo], rio Amazonas floodplain, 03°05′28″S, 059°53′09″W. MPEG 967, 1 (part), 86 mm, MPEG 970 (part), 1, 120 mm, MPEG 978, 1, 202 mm, MZUSP 30044 (part), 98, 82-233 mm, mun. Tefé, lago Jurupari, rio Tefé, 03°48′S, 065°00′W. MPEG 968, 3, 140-157 mm, MPEG 975, 3, 157-203 mm, MZUSP 30047, 5, 195-250 mm, mun. Tefé, lago Supiã-Puçu, rio Tefé, 03°45′S, 064°57′W. MPEG 977, 2, 87-225 mm, MZUSP 30046, 6, 110-225 mm, MZUSP 30048, 31, 74-235 mm, mun. Tefé, Arana-tuba, rio Tefé, ca. 04°02′S, 065°01′W. MPEG 979, 7 (part), 110-200 mm, mun. Tefé, Ipanema da Baixa, rio Tefé, no coordinates. MPEG 980, 23, 84-242 mm, mun. Tefé, Janari-Atuba, rio Tefé, ca. 03°52′S, 065°01′W. MPEG 1123 (part), 1, 142 mm, mun. Tefé, Costa Capivara, rio Solimões, ca. 03°16′38″S, 064°38′09″W. MPEG 1128, 2, 226-260 mm, mun. Iranduba, rio Solimões nr. Manaus, ca. 03°17′S, 060°11′W [coordinates for Iranduba]. MPEG 22738, 1, 305 mm, Mamirauá Reserve, lago Mamirauá, 02º59′38″S, 064°54′26″W. MPEG 22739, 1, 165 mm, mun. Tefé, igarapé Repartimento, affl. lago Tefé, rio Tefé, 03°24′19″S, 064°43′54″W. MZUSP 30045, 79 (1 CS), 59-233 mm, Jauari-atuba, rio Tefé, ca. 03°56′S, 065°01′W. MZUSP 30049 (part), 2, 55-90 mm, MZUSP 30057, 2, 56-62 mm, Vista Escura, rio Tefé, no coordinates. MZUSP 30061 (part), 17, 85-157 mm, MZUSP 30062, 5, 48-98 mm, lago Mucura, rio Tefé, no coordinates. MZUSP 62060, 2, 87-99 mm, Poça de Praia, Tapera, rio Negro, 00°11′S, 064°04′W. MZUSP 78032 (part), 1, 181 mm, mun. Maraã, Paraná do Castanho, lago Amanã, affl. rio Japurá, 02°44′S, 064°39′W. MZUSP 91651, 1, 164 mm, rio Uapés, affl. rio Negro, no coordinates [listed coordinates invalid]. MZUSP 92250, 65, 123-225 mm, mun. São Gabriel da Cachoeira, igarapé Cunurim, affl. rio Tiquié, ca. 500 m below São José II, affl. rio Uaupés, affl. rio Negro, 00°13″N, 069°36″W. MZUSP 92496, 17, 95-205 mm, mun. São Gabriel da Cachoeira, igarapé Castanha, nr. mouth, affl. rio Tiquié, affl. rio Uaupés, affl. rio Negro, 00°12″N, 069°35″W. MZUSP 93091, 1, 220 mm, mun. São Gabriel da Cachoeira, igarapé Castanha nr. São Pedro, affl. rio Tiquié, affl. rio Uaupés, affl. rio Negro, 00°11″N, 069°35″W. MZUSP 94034, 7, 105-160 mm, MZUSP 99169, 7, 73-197 mm, canal do lago Amanã, affl. rio Japurá, ca. 03°00′S, 064°23′W. MZUSP 95226 (part), 1, 158 mm, mun. Santa Isabel do rio Negro, nr. Paricatuba, lagoon on margin of rio Negro, 00°31′S, 065°01′W. USNM 198081, 2, 138- 181 mm, igarapé da Mãe Joana, lago Grande do Manacapuru, affl. rio Solimões, ca. 03°13′S, 060°44′W. USNM 229425, 1, 192 mm, USNM 306868, 2, 159-190 mm, mun. Manaus, lago Janauari, nr. mouth, rio Amazonas floodplain, ca. 03°13′S, 060°00′W. USNM 300973, 2, 67-120 mm, rio Unini, affl. rio Negro, ca. 01°41′S, 061°31′W [coordinate for mouth of rio Unini]. USNM 306835, 7, 190-259, mun. Manaus, lago do Janauari, rio Amazonas floodplain, ca. 03°13′S, 060°00′W. USNM 306878, 1, 215 mm, lago Camaleão, Ilha da Marchantaria, rio Solimões floodplain, 03°14′22″S, 059°56′37″W. USNM 306902, 1, 80 mm, USNM 306925, 1, 167 mm, lago Terra Preta, lago do Janauari, rio Amazonas floodplain, ca. 03°13′S, 060°00′W. USNM 306904, 3, 190-257 mm, USNM 306934, 1, 259 mm, lago Janauari, rio Amazonas floodplain, ca. 03°13′S, 060°00′W. USNM 306921, 1, 234 mm, lago Canta Galos, lago Janauari, rio Amazonas floodplain, 03°13′S, 060°00′W. USNM 327307, 1, 96 mm, mun. Barcelos, lago de Caatinga, rio Ererê, affl. rio Negro, ca. 00°14′S, 063°53′W. Mato Grosso. INPA 4385, 3, 139-169 mm, stream nr. Castanhal, rio Aripuanã, affl. rio Madeira, Amazonas dr., ca. 10°10′S, 059°29′W [coordinates for town of Aripuanã]. MNRJ 25152, 4, 62-93 mm, mun. Ribeirão Cascalheira, Ribeirão Manda Brasa, affl. rio Suiá-miçu, affl. rio Xingu, Amazonas dr., ca. 12°54′S, 051°49′W. MZUSP 48311 (part), 1, 122 mm, Fazenda Santo Antônio, Baía da Sede, Pantanal do Paiaguás, nr. Coxim, rio Paraguai, Paraná dr., 18°30′S, 054°45′W. MZUSP 90178, 3, 129-182 mm, mun. Cáceres, rio Sepotuba (lower course), affl. rio Paraguai, Paraná dr., 15°47′33″S, 057°39′20″W. MZUSP 95068 (part), 5, 177-207 mm, mun. Barão de Melgaço. rio Mutum, between Vila de Mimoso and Joselandia (Pantanal de Paiaguás), rio Paraguai, Paraná dr., 16°19′30″S, 055°49′59″W. Mato Grosso do Sul. MZUSP 36436, 1, mun. Corumbá, Ladário, rio Paraguai, Paraná dr., 19°00′S, 057°36′W. Pará (localities from Amazonas dr.). AMNH 12966, 2, 213-327 mm, rio Tocantins, high above waterfall, no coordinates. BMNH 1926.10.27.241-242, 2, 204-207 mm, Monte Alegre, rio Amazonas, 02°00′S, 054°00′W. INPA 6399, 1, 142 mm, margin of lago Tapagem, rio Trombetas, 01°24′S, 056°51′W. MCP 16307, 1, 184 mm, mun. Belém, nr. Belém, Baía de Marajó, ca. 01°26′S, 048°23′W. MCP 23360, 2, 125-188 mm, Ourém, rio Guamá, affl. Baía de Marajó, ca. 01°33′S, 047°06′W. MCP 23361, 1, 146 mm, Tomé-Açu, rio Acará-Mirim, affl. rio Acará, affl. Baía de Marajó, 02°25′S, 048°09′W. MCP 28565, 1, 32 mm, Ihnangapi, São Domingos do Capim, affl. rio Guamá, affl. Baía de Marajó, 01°27′02″S, 47°48′26″W. MCP 49397, 1, mun. Santarém, rio Mentai at Cachoeirinha do Mentai, affl. rio Arapiuns, affl. rio Tapajós, 02°43′12″S, 055°36′15″W. MCP 49399, 2, mun. Santarém, Igarapé do Henrique, affl. Rio Maró, affl. rio Arapiuns, affl. rio Tapajós, 02°51′31″S, 055°41′04″W. MCP 49402, 1, mun. Curuá, Lago Preto, Ilha São Luiz, rio Amazonas, 02°06′22″S, 055°10′17″W. MCP 49404, 6; ZUEC 12326, 4, mun. Belterra, stream at Aramanai, affl. rio Tapajós, 02°43′03″S, 055°00′07″W. MCP 49405, 1, mun. Belterra, rio Tapajós at São Domingos, 02°45′02″S, 055°01′05″W. MCP 49406, 3, mun. Santarém, stream affl. Lago Anumã, affl. Rio Tapajós, 02°37’27″S, 055°11’09″W. MCP 49408, 1, mun. Santarém, Igarapé Sucurijú, affl. rio Mentai, affl. rio Arapiuns, affl. rio Tapajós, 02°43′38″S, 055°35′41″W. MCP 49409, 3, mun. Santarém, rio Maró, nr. Fé em Deus, affl. rio Arapiuns, affl. rio Tapajós, 02°50′58″S, 055°41′06″W. MCZ 45194, 1, 192 mm, mun. Belém, nr. Icoaraci, igarapé Paracuri, affl. Baía de Marajó, ca. 01°18′S, 048°28′W. MCZ 165862 (part), 1, 178, mun. Santarém, Santarém and environs, rio Tapajós, ca. 02°26′S, 54°41′W. MPEG 1113, 2, 130-197 mm, MPEG 1114, 6, 75-135 mm, MPEG 1115, 5, 112-230 mm, rio Guamá at Belém, affl. Baía de Marajó, ca. 01°24′S, 048°25′W. MPEG 1131, 1, 201 mm, MPEG 2397, 8, 150-320 mm, mun. Castanhal, Boa Vista do Apeú, rio Apeú, affl. rio Guamá, affl. Baía de Marajó, ca. 01°18′S, 047°59′W. MPEG 1132, 1, 182 mm, MPEG 1133, 1, 173 mm, MPEG 2731, 1, 158 mm, MPEG 6774, 4, 125-192 mm, mun. Cachoeira do Arari, Taperebá, rio Goapi, llha de Marajó, affl. Baía de Marajó, ca. 01°00′S, 048°57′W [coordinates for Cachoeira do Arari]. MPEG 3720, 1, 154 mm, MPEG 3736, 1, 135 mm, MPEG 3739, 1, 164 mm, MPEG 4066, 1, 146 mm, mun. Melgaço, Estação Científica Ferreira Pena, rio Puraquequara, affl. rio Anapú, affl. rio Pará, affl. Baía de Marajó, ca. 01°44′S, 051°27′W. MPEG 4706, 2, 162-177 mm, mun. Ourém, rio Guamá, Furo do Guamá, Lagoa Velha, affl. Baía de Marajó, ca. 01°33′S, 047°06′W [coordinates for Ourém]. MPEG 6385, 1, 127 mm, mun. Peixe-Boi, rio Peixe-Boi, affl. rio Maracanã (rio Amazonas estuary), 01°11′31″S, 047°18′14″W [coordinates for rio Peixe-Boi at Peixe-Boi]. MPEG 6775, 3, 110- 147 mm, mun. Cachoeira [do Arari], mouth of rio Goapi, llha de Marajó, affl. Baía de Marajó, 01°00′27″S, 048°57′44′W. MPEG 6884, 4, 150-270 mm, mun. Paragominas, igarapé Poraquequara, behind camp of Companhia Vale do rio Doce, affl. rio Capim, affl. rio Guamá, affl. Baía de Marajó, 03°14′50″S, 047°45′40′W. MPEG 6917, 1, 110 mm, MPEG 7295, 6, 110-417 mm, MPEG 7397, 1 (part), 43 mm, mun. Paragominas, igarapé Paraquequara at Fazenda do Sr. Paulo/ Fazenda Monte Santo, affl. rio Capim, affl. rio Guamá, affl. Baía de Marajó, 03°16′05″S, 047°46′05′W. MPEG 7310, 1, 180 mm, mun. Paragominas, Vale do rio Doce facility, confl. igarapé Cachoerinha and Paraquequara, affl. rio Capim, affl. rio Guamá, affl. Baía de Marajó, 03°09′25″S, 047°41′51′W. MPEG 7319, 1 (part), 175 mm, mun. Paragominas, Fazenda Potiritá, igarapé Potiritá, affl. rio Potiritá, affl. rio Capim, affl. rio Guamá, affl. Baía de Marajó, 03°12′13″S, 047°39′52′W. MPEG 9884, 2, 63-68 mm, mun. Portel, Floresta Nacional Caxiuanã, affl. rio Anapú, affl. rio Pará, affl. Baía de Marajó, ca. 01°44′S, 051°26′W. MPEG 12573, 2, 139-188 mm, mun. Benevides, Itá, affl. rio Guamá, affl. Baía de Marajó, ca. 01°21′S, 048°14′W. MPEG 17818, 1, 92 mm, mun. Benevides, igarapé Taiassuí, affl. rio Guamá, Baía de Marajó, 01°23′46″S, 048°14′59′W. MZUSP 8412, 7, mun. Santarém, igarapé Jacundá, Alter do Chão, affl. rio Tapajós, 02°29′S, 054°47′W. MZUSP 15567, 1, 165 mm, Cabeceira da Serrinha, lago Jacaré (Reserva Biológica de Trombetas), rio Trombetas, 01 ° 20′S, 056°50′W. MZUSP 22291, 1, 167 mm, mun. Castanhal, Boa Vista, rio Apeu, ca. 01°17′S, 047°55′W. MZUSP 23865, 1, 90 mm, rio Caranandeua, rio Capim, affl. rio Guamá, affl. Baía de Marajó [coordinate for mouth of rio Capim], 01°40′S, 47°46′W. MZUSP 23894, 1, rio Capim, lago Jurunundéua, no coordinates. MZUSP 25006, 5, 197-368 mm, rio Curuã-Una, just upstream of dam, 02°49′S, 054°16′W. SU 54502, 1, 113 mm, SU 54503, 3, SU 64189, 1, Cabeceira lago Grande, nr. Santarém, Ajamury, ca. 02°26′S, 054°41′W [coordinates for Santarém]. UF 36600, 1, 54 mm, igarapé Pirelli, affl. rio Maguari, affl. Baía de Marajó, 01°21′24″S, 048°19′36″W. UF 238564, 11, 119-237 mm, UF 238565, 11, 106-293 mm, UF 238566, 4, 159-205 mm; UF 238567, 12, 77-234, UF 238568, 12, 91-255, stream at SEPAq station, 39 km SE Santarém on rd. to Santa Rosa, 02˚40’01”S, 054˚33’09”W. ZUEC 12327, 6, mun. Santarém, igarapé do Mato Grosso, nr. Jaguarari, affl. rio Tapajós, 02°55′01″S, 055°03′54″W. ZUEC 12331, 3, mun. Santarém, lago Bravo, nr. Santo Amaro, affl. rio Tapajós, 02°58′22″S, 055°13′42″W. ZUEC 12333, 5, mun. Santarém, igarapé Santo Amaro, nr. Santo Amaro, affl. rio Tapajós, 02°59′15″S, 055°13′59″W. ZUEC 12334, 6, mun. Santarém, Igarapé do Macaco, affl. rio Mentai, affl. rio Arapiuns, affl. rio Tapajós, 02°40′28″S, 055°35′55″W. ZUEC 12335, 1, mun. Santarém, Igarapé Branquinho, affl. rio Mentai, affl. rio Arapiuns, affl. rio Tapajós, 02°41′48.4″S, 055°35′43″W. Rondônia (localities from rio Madeira dr., Amazonas dr.). FMNH 117761, 1, 158 mm, Maciel, rio Guaporé, affl. rio Mamoré, ca. 12°30′S, 062°20′W. INPA 9722, 3, 92-212 mm, INPA 9726, 18, 130-287 mm, rio Pacaás Novos, nr. confl. with rio Guaporé, ca. 15 km Guajará Mirim, affl. rio Mamoré, 10°51′S, 065°16′W. INPA uncat. (POLO-663), 2, 140- 148 mm, rio Guaporé opposite Costa Marquez, affl. rio Mamoré, 12°27′S, 064°20′W. INPA uncat. (POLO-683), 13, INPA uncat. (POLO-731), 18, rio Pacaás Novos, ca. 15 km upstream of Guajará-Mirim, affl. rio Mamoré, 10°54′S, 065°09′W. MCP 46938, 2, 100- 200 mm, mun. Calamã, Calamã, rio Madeira floodplains lake, 08º01′37″S, 062°52′28″W. UFRO-I 6476, 38, 59-290 mm, lago Cuniã, rio Madeira floodplain, 08°19′40″S, 063°30′11″W. UFRO-I 6483, 1, 40 mm, nr. Sítio Santa Helena, in front of Ilha das Pedras, rio Karipunas, 09°11′32″S, 064°34′17″W. UFRO-I 6485, 42, 53- 385 mm, UFRO-I uncat. (field no. CAU 2010010701), 3, 180-245 mm, mouth of rio Cautário, 12°10′51″S, 064°34′04″W. UFRO-I 6487, 9, 105-215 mm, rio Guaporé upstream of Pedras Negras, affl. rio Mamoré, 12°52′03″S, 62°52′38″W. UFRO-I 6490, 3, 88-117 mm, UFRO-I 6516, 1, 255 mm, lago Cuniã, 1 km ICMBio base, rio Madeira floodplain, 08°19′20″S, 063°30′14″W. UFRO-I 6496, 1, 83 mm, mouth of rio Pacaás Novos, affl. rio Mamoré, 10°52′07″S, 065°15′42″W. UFRO-I 6503, 4, 118-160 mm, Furo Variante, lago Cuniã, rio Madeira floodplain, 08°21′18″S, 063°30′11″W. UFRO-I 6505, 9, 37-122 mm, Arrozal do lago, rio Madeira floodplain, 08°19′36″S, 063°29′59″W. UFRO-I 6512, 2, 195-204 mm, Arrozal do lago, rio Madeira floodplain, 08°21′10″S, 063°30′26″W. UFRO-I 7924, 1, female, 166 mm, mun. Porto Velho, igarapé Mato Grosso, nr. campus Universidade Federal de Rondônia, nr. Cachoeira Santo Antônio, affl. rio Madeira, 08°49′41″S, 063°56′30″W. UFRO-I 7925, 11 (5 immature, 136-253 mm, 1 female, 203 mm, 5 male, 181-297 mm), mun. Porto Velho, lago Cuniã, rio Madeira floodplain, ca. 08°19′S, 063°28′W. UFRO-I uncat. 1, 181 mm, rio Madeira at Abunã, ca. 09°42′S, 065°21′W. Roraima (localities from rio Branco dr., affl. rio Negro, Amazonas dr.). INPA 7358, 1, INPA 7359, 1, INPA 7360, 1, INPA 7361, 1, INPA 73661, 1, INPA 7372, 1, INPA 7381, 1, INPA 7382, 1, INPA 7388, 1, INPA 7392, 1, lago Caracanã, 23 km Normândia on hwy. RR-202, 03°54′12″N, 059°49′17″W. INPA 7373, 1, INPA 73791, 119 mm, INPA 7380, 1, igarapé do Gentil, 34 km Boa Vista on Boa Vista to Bonfim hwy., ca. 02°58′N, 060°26′W. INPA 7413, 3, INPA 7414, 2, Fazenda Santa Cecília, 7 km Boa Vista on Boa Vista- Bonfim hwy., 02°48′N, 060°36′W. INPA 7424, 2, 112-159 mm, Fazenda Chico Paraíba, ca. 4 km Bonfim, rio Tacutu, ca. 03°21′N, 059°50′W. INPA 9833, 3, 80-108 mm, Ilha de Maracá, stream at end of island, rio Uraricoera, 03°22′N, 061°23′W. MZUSP 31775, 1, 221 mm, igarapé do Cujobim, ‘rio Branco′ opposite Ilha de Maracá, rio Uraricoera, ca. 03°21′N, 061°26′W. MZUSP 31777, 1, 176 mm, igarapé do Bota Panela, nr. Cachoeira do Bem Querer on rio Branco, ca. 01°55′N, 061°00′W. Colombia. Guainía. MBUCV-V 7536, 1, caño Caramacoa, apróx. 45 min de Puerto Inírida, affl. río Inírida, affl. río Guainía, Orinoco dr., ca. 03°51′N, 067°55′W. French Guiana. Cayenne. CU 71942, 4, Kaw River, ca. 3.5 km NW Kaw, Kaw River dr., 04°31′N, 052°04′W. MNHN 1999-1325, 3 (of 7), 210-224 mm, Kaw River dr., no coordinates. MNHN 1999-1374, 1, 211 mm, crique Gabrielle, Comté River dr., ca. 04°44′N, 052°19′W. Guyana. Demerara Mahaica. AUM 27917, 7, 12356, Maduni stop-off, 22.3 mi. from Georgetown, Conservancy Canal, affl. Maduni River, Mahaica River dr., 06°30′01″N, 058°02′14″W. CAS 67700, 1, 164 mm, FMNH 53329, 1, 52 mm, FMNH 53337, 1, 143 mm, INHS 49037, 1, 270 mm, Lama stop-off, Conservancy Canal, affl. Lama River, Mahaica River dr., 06°37′33″N, 057°55′55″W. FMNH 96203, 1, 44 mm, Kuru Kuru creek on Soesdyke-Linden hwy., Demerara River dr. 06°24′12″N, 058°14′26″W. INHS 49063, 9, 104-158 mm, Maduni stop-off, Conservancy Canal, affl. Maduni River, affl. Mahaica River, 06°30′01″N, 058°02′14″W. Potaro Siparuni. ANSP 175955, 1, 70 mm, creek, affl. Essequibo River, ca. 18 min. upstream from Maipuri campsite, Essequibo River dr., ca. 04°34′N, 058°35′W. ANSP 177494, 1, 147 mm, Siparuni River, Red Hill Creek between Levi Falls and Blackwater camp, Essequibo River dr., 04°44′14″N, 058°59′17″W. Upper Demerara-Berbice. AMNH 13421, 1, 169 mm, AMNH 30418, 1, Malali, Mari-Mari River, Demerara River dr., 05°37′N, 058°21′W. AUM 35812, 1, 127 mm, unnamed river at Kurukupari, Essequibo River dr. 04°39′41″N, 058°40′31″W. CAS 67703, 2, Demerara River at Wisden (formerly Wismar), Demerara River dr. 06°00′N, 058°18′W. CAS 67705, 2, 156-167 mm, FMNH 53338, 2, Gluck Island, Essequibo River, nr. Rockstone, Essequibo River dr., 05°58′N, 058°31′W. FMNH 53339, 1, Kumaka, Berbice River dr., 05°35′N, 057°56′W. INHS 49107, 1, 81 mm, 5.05 mi. SSW Linden, Demerara River dr., 05°56′00″N, 058°18′22″W. INHS 49143, 1, 129 mm, 5.05 mi. SSW Linden, Demerara River dr., 05°56′00″N, 058°18′22″W. ROM 86803, 3, 157-237 mm, ROM 88618, 5, 143-270 mm, side channel by island, Berbice River, Berbice River dr., 05°09′03″N, 058°11′46″W. Upper Takutu-Upper Essequibo (localities from Takutu River are in the rio Branco dr., affl. rio Negro, Amazonas dr.). ANSP 179504, 2, 106- 133 mm, AUM 35863, 2, 83-104 mm, stream 10.3 km NW Karanambo, affl. Rupununi River, Essequibo River dr., 03°48′27″N, 059°23′06″W. AUM 38187, 1, 142 mm, Kuyuwini River, 48.4 km E Kuyuwini Landing, Essequibo River dr., 02°03′54″N, 058°48′33″W. BMNH 1972.7.27.447-450, 4, 133-156 mm, Dadanawa pools, Rupununi River, Essequibo River dr., ca. 02°50′N, 059°31′W. BMNH 1972.7.27.451-455, 6, 64-158 mm, “Guyana”, no coordinates. CU 71959, 9, Jawar pond, Manari Ranch, N Lethem, Rupununi savanna, affl. Takutu River, ca. 03°26′N, 059°46′W (listed by Sullivan, 1997). MCZ 48553, 1, 204 mm, Agua Branca River, affl. Manari River, affl. Takutu River, ca. 03°29′N, 059°48′W. MCZ 48554, 2, 157-191 mm, dry creek bed, 10 mi. E Nappi, affl. Takutu River, ca. 03°25′N, 059°25′W. MCZ 165855, 1, 241 mm, small pond 5 mi. N Manari Ranch, Takutu River, ca. 03°26′N, 059°46′W. UMMZ 215583, 1, 244 mm, Shebe pond, Rupununi, no coordinates. UMMZ 215603, 1, 218 mm, pond at Juari Ranch, E Takutu River, no coordinates. Region not specified. UMMZ 187500, 3, 118-184 mm, aquarium specimen, no coordinates. USNM 376799, 1, 183 mm, Waterguage Pond, unknown locality in Guyana, no coordinates. Peru. Loreto (all localities are from Amazonas dr.). ANSP 166267, 1, 76 mm, stream of río Yanayacu, W Miraflores, rio Marañón, ca. 04°42′S, 074°17′W. ANSP 167729, 8, 98-172 mm, stream 0.5 mi. below Santa Clara (R bank), río Nanay, ca. 03°46′S, 073°20′W. ANSP 178218, 4, 81-156 mm, ANSP 178220, 2, 55-63 mm, caño Santa Rita, R. bank affl. río Nanay, nr. Pueblo Pampa Chica, 03°45′23″S, 073°17′28″W. ANSP 178655, 1, 172 mm, río Nanay at Pueblo Pampa Chica, 03°45′09″S, 073°17′00″W.ANSP 180311, 1, 121 mm, río Nanay, upstream from Santa Clara, 03°46′45″S, 073°22′06″W. ANSP 182935, 3, 119-159 mm, caño Shirui (also known as Santa Rita), R. bank affl. río Nanay, nr. Pueblo Pampa Chica, 03°45′23″S, 073°17′28″W. ANSP 191848, 1, 176 mm, río Nanay, R. bank, downstream mouth caño Shirui, 03°45′06″S, 073°17′14″W. INHS 36785, 2, 117-137 mm, quebrada Santa Clara, río Nanay, ca. 03°47′S, 073°20′W. INHS 52490, 3, 99-136 mm, caño Santa Rita, nr. Pampa Chica, affl. río Nanay, 03°45′23″S, 073°17′28″W. MCP 43159, 1, 183 mm, UF 114499, 4, 128-250 mm, UF 116556, 1, female, 242 mm, stream at km 23 on Iquitos-Nauta hwy., affl. río Nanay, 03°56′38″S, 073°23′54″W. MUSM 1992, 9, 108-331 mm, río Nanay at Iquitos, ca. 03°42′S, 073°15′W. MUSM 7123 (part), 5, 73-85, Laguna Rimachi, río Pastaza, affl. río Marañón, 04°25′S, 076°43′W. MUSM 44702, 3 (1 immature, 175 mm, 2 female, 279-296 mm), forest stream nr. Jenaro Herrera, affl. río Ucayali, 04°54′26″S, 073°36′44″W. SU 66949, 1, 41 mm, río Ampiyacu nr. Pebas, ca. 03°19′S, 071°50′W. UF 116549, 1, immature, 65 mm, río Nanay, N bank, 1 km upstream Mishana, 03°52′12″S, 073°29′38″W. UF 131127, 1, 130 mm, Iquitos, procured by ornamental fish catchers, no coordinates. UF 148471, 1, 52 mm, quebrada Sapuenillo, nr. Jenaro Herrera, affl. río Ucayali, 04°54′26″S, 073°36′44″W. UF 184006, 17 (3 immature, 50-135 mm, 9 female, 157-285 mm), Laguna Quistococha, río Itaya, 03°49′56″S, 073°19′12″W. USNM 284624, 9, 108-331 mm, río Amazonas, nr. Iquitos, 03°45′S, 073°15′W. ZMH 11628 (part), 1, 80 mm, between Iquitos and Leticia, río Amazonas, no coordinates. Madre de Dios (localities from río Madre de Dios dr., affl. Río Beni, affl. Río Madeira, Amazonas dr.). MUSM 9159, 1, 288 mm, MUSM 9605, 4, 158-207 mm, Reserva Nacional ( RN) de Tambopata, Laguna Sandoval, 12°26′30″S, 069°02′18″W. MUSM 25368, 1, Las Piedras, quebrada Malecón, affl. río Manuripe, ca. 12°30′S, 069°14′W. USNM 264073, 1, 235 mm, RN de Tambopata, Laguna Cocococha, 5.1 km E Explorer′s Inn, 12°49′00″S, 069°16′30″W. Suriname. Marowijne. UF 177359, 2 (1 female, 261 mm, 1 male, 210 mm), small stream on rd. from Paramaribo to Albina, affl. Cottica River, Commewijne River dr., 05º34′50″N, 054º15′31″W. Nickerie. USNM 225560, 1, 65 mm, Corantijn River at km 180, side channel, Corantijn River dr., ca. 05°54′N, 57°04′W. USNM 302005, 1, 91 mm, affl. Sisa Creek, N side, ca. 700 m downstream of crossing of Amotopo-Camp Geologie rd., Corantijn River dr., 03°42′N, 057°42′W. Para. UF 177361, 1, female, 207 mm, mun. Zanderij, Kola kreek, affl. Para River, Suriname River dr., 05°27′09″N, 055°14′58″S. Sipaliwini. BMNH 1981.6.9.932-986 (part), 1, 190 mm, stream entering Lucie River, Corantijn River dr. ca. 03°35′N, 057°40′W. USNM 225561, 1, 191 mm, Matapi creek ca. 1 km intersection with Corantijn River, Corantijn River dr., 05°00′N, 057°16′W. USNM 225563, 2, 95-170 mm, stream ca. 0.5 km inland of Camp Mataway, Corantijn River dr., ca. 04°48′N, 057°43′W. Venezuela. Amazonas. FMNH 94429, 4, 161-183 mm, “upper Orinoco”, Orinoco dr., no coordinates. MBUCV-V 8063, 1, 104 mm, caño Moriche, ca. 10 km N San Fernando de Atabapo, affl. río Orinoco, Orinoco dr., ca. 03°57′N, 067°38′W. MBUCV-V 14710, 1, 95 mm, nr. Santa Lucia, rio Negro, Amazonas dr., ca. 01°18′N, 066°52′W. MBUCV-V 14734, 1, 204 mm, small affl. río Orinoco, Puerto Ayacucho-El Burro rd., Orinoco dr., ca. 05°47′N, 067°29′W. MCNG 21516, 3, Maroa, río Guainía, affl. rio Negro, Amazonas dr., ca. 02°43″N, 067°33′W (listed by Sullivan, 1997). MCNG 22090, 1, Piaroa San José, río Yureba, Orinoco dr., ca. 04°02′N, 067°33′W (listed by Sullivan, 1997). UF 177350, 7 (2 immature, 170-199 mm, 5 female, 167-201 mm), caño Viejita, rd. from San Fernando de Atabapo to Santa Barbara, affl. río Atabapo, Orinoco dr., 03°55′59″N, 067°36′34″W. Anzoátegui. MBUCV-V 25751, 1, 325 mm, Hato Morichalito, río Zuata, Orinoco dr., ca. 08°33′N, 064°57′W. Apure (localities from Orinoco dr.). ANSP 141616, 4, Jabillal, nr. San Fernando de Apure, affl. río Arauca, ca. 07°44′N, 067°58′W. AUM 22561, 1, 130 mm, caño Guarico, affl. río Apure, 07°42′47″N, 069°19′50″W. AUM 22756, 19, 100-190 mm, INHS 89761, 11, 127-164 mm, caño La Pastora, affl. río Apure, 07°26′40″N, 069°26′05″W. MBUCV-V 13229, 1, 246 mm, Mantecal, río Arauca, 07°34′N, 069°08′W. MCNG 2138, 1, MCNG 2489, 22, MCNG 3635, 5, MCNG 3715, 44, MCNG 3799, 6, MCNG 3898, 27, MCNG 4906, 2, MCNG 5134, 4, MCNG 7467, 2, MCNG 28738, 22, Módulo UNELLEZ, río Caicara, affl. río Apure, 07°24′N, 069°32′W (listed by Sullivan, 1997). MCNG 3906, 26, Muñoz, Módulo F.C., río Caicara, aff, río Apure, ca. 07°35′N, 069°25′W (listed by Sullivan, 1997). MCNG 9777, 3, caño Guaritico, aff río Apure, ca. 07°45′N, 069°03′W (listed by Sullivan, 1997). MCNG 10144, 5, MCNG 10344, 1, MCNG 11032 (part), 1, MCNG 12566 (part), 4, MCNG 15744, 2, caño Maporal, nr. módulo UNELLEZ, affl. río Caicara, affl. río Apure, 07°24′N, 069°32′W (listed by Sullivan, 1997). MCNG 28579, 5, affl. of río Caicara, no precise locality, no coordinates (listed by Sullivan, 1997). TNHC 14928, 10, 146-201 mm, caño Maporal, nr. módulo UNELLEZ, affl. río Caicara, affl. río Apure, 07°27′N, 069°32′W. TNHC 17490, 5, 150-244 mm, TNHC 47217, 1, 212 mm, nr. módulo UNELLEZ, río Caicara, affl. río Apure, ca. 07°24′N, 069°32′W. UF 77335, 4, 162-208 mm, ca. 30 km SW La Ye, caño Caicara, affl. río Guaratico, affl. río Apure, 07°45′N, 069°03′W. UF 176887, 10 (1 immature, 197 mm, 1 female, 187 mm, 3 male, 153- 170 mm, 5 unsexed [2 CS], 74-231 mm), MCNG 9698, 1, Hato El Frio, nr. Mantecal, floodplain lake of río Guaratico, affl. río Apure, 07°49′32″N, 068′55′23″W. Bolívar. ANSP 166372, 1, 140 mm, lago Maldonado, El Almacén, río Orinoco floodplain, Orinoco dr., ca. 08°06′N, 063°48′W.AUM 36512, 3, 204-288 mm, northernmost arm of Uraima Falls, río Paragua, affl. río Caroní, Orinoco dr., 06°18′05″N, 063°37′39″W. MBUCV-V 3971, 38, 10-45 mm, floodplain lake of río Las Claritas, on El Dorado-Santa Elena de Uairén hwy., affl. río Cuyuní, Essequibo River dr., ca. 06°10′N, 061°25′W. MBUCV-V 4013, 2, stream at km 67 on El Dorado-Santa Elena de Uairén hwy., affl. río Cuyuní, Essequibo River dr., ca. 06°13′N, 061°21′W. MBUCV-V 7457, 8, 43-66 mm, stream, km 88 on El Dorado-Santa Elena de Uairén hwy., affl. río Cuyuní, River Essequibo dr., 06°05′N, 061°23′W. MBUCV-V 9490, 1, 337 mm, MBUCV-V 9513, 1, 377 mm, MBUCV-V 9517, 1, 220 mm, MBUCV-V 9791, 1, 168 mm, MBUCV-V 14029, 1, 220 mm, 40 km S El Dorado, Isla de Jacobo, nr. raudal de Kinotovaca, affl. río Cuyuní, River Essequibo dr., ca. 06°23′N, 061°37′W. MBUCV-V 9537, 1, 262 mm, Boca del río Chicanán (at El Dorado), affl. río Cuyuní, River Essequibo dr., ca. 06°42′24″N, 061°38′05″W. MBUCV-V 10693, 3 (2 examined), 30-42 mm, La Paragua, río Paragua, aff río Caroní, Orinoco dr., 06°50′N, 63°22′W. MHNLS 5720, 2, MHNLS 6992, 1, Bandera, lago Guri, rio Caroní, Orinoco dr., 07°46′N, 062°59′W (listed by Sullivan, 1997). MZUSP 96453, 1, 59 mm, mun. Caicara del Orinoco, rio caño, Pelo Ojo, Orinoco dr., 07°32′22″N, 066°08′29″W. MZUSP 96484, 21, 23-162 mm, mun. Caicara del Orinoco, Laguna de Castilleros, margin of río Orinoco, Aquaculture Station, Universidad de Oriente, Orinoco dr., 07°30′51″N, 066°09′ 20W. SU 54418, 1, 173 mm, SU 54495, 1, 188 mm, SU 64174, 10, mun. Caicara del Orinoco, caño de Quiribana, Orinoco dr., ca. 07°32′N, 066°08′W (listed by Sullivan, 1997). TCWC 8308.18, 2, 106-114 mm, TCWC 8310.24, 2, 182-185 mm, TCWC 8311.24, 2, 158-181 mm, TCWC 8320.05, 1, 297 mm, Campamento del Guri, Guri Reservoir, río Caroní, Orinoco dr., ca. 07°46′14″N, 063°00′34″W. Delta Amacuro. MBUCV-V 10352, 4 (3 examined), 192-209 mm, caño El Chano, Coporito arriba, nr. Tucupita, affl. caño Mamano, río Orinoco delta, Orinoco dr., ca. 09°03′N, 062°03′W. Guárico (localities from Orinoco dr.). MBUCV-V 25739, 1, 118 mm, S Requena, mouth of río Zuata, 07°58′N, 065°31′W. MCNG 1760, 1, Hato Santiago, no coordinates. Monagas (localities from Orinoco dr.). LACM 43349-12, 16, 92- 199 mm, MBUCV-V 10696, (part) 20 (4 CS), 97-222 mm, Laguna Guatero nr. Barrancas, affl. río Orinoco, ca. 08°42′N, 062°12′W. MBUCV-V 18905, 1, 43 mm, MBUCV-V 22404, 12, 71-214 mm, río Morichal Largo, río Orinoco delta, 09°26′N, 062°24′W. MCNG 11201, 1, río Uracoa, río Orinoco delta, 09°00″N, 062°21′W. MCNG 15932, 4, río Yabo, at bridge nr. El Pelón, río Orinoco delta, ca. 08°57″N, 062°47′W. MHNLS 6417, 3, Laguna San José, nr. Coloradito, río Orinoco delta, ca. 08°45′N, 063°29′W. MHNLS 6621, 1, lake at Los Cocos, 08°32′N, 062°25′W. Region not specified. ANSP 85366, 1, 138 mm, La Fria, Pueblo Nueva, no coordinates.

Figures

Fig. 1. Live individuals of 12 sympatric species of Brachyhypopomus and one species of Microsternarchus from the vicinity of Tefé, Amazonas, Brazil (Amazonas dr.). a. Brachyhypopomus batesi MCP 45312 (WC01.191293b), immature, 102 mm TL. b. Brachyhypopomus beebei head – uncat., immature, 75 mm TL; body – MCP 45450 (WC04.090600), female, 178 mm TL. c. Brachyhypopomus belindae MCP 45430, paratype, immature, 104 mm TL (photographed out of water, close up of head not available). d. Brachyhypopomus bennetti MCP 45451, male, 196 mm TL. e. Brachyhypopomus brevirostris uncat., immature, 224 mm TL. f. Brachyhypopomus flavipomus MCP 45453 (WC09.090600), female, 98 mm TL. g. Brachyhypopomus hamiltoni MCP 45482 (WC05.080301), holotype, female, 97 mm TL. h. Brachyhypopomus hendersoni MCP 45489, female, 164 mm TL. i. Brachyhypopomus pinnicaudatus MCP 45455, female, 135 mm TL. j. Brachyhypopomus regani, MCP 45285 (WC02.100301), male, 119 mm TL. k. Brachyhypopomus sullivani MCP 45464 (WC04.210201), immature, 79 mm TL. l. Brachyhypopomus walteri MCP 45458 (WC 03.090600), male, 161 mm TL. m. Microsternarchus bilineatus uncat., 85 mm TL.

Fig. 17. Brachyhypopomus brevirostris. a. MCP 45470 (WC11.110801b), immature female, 193 mm TL, (head only, specimen fixed in formalin); Brazil, rio Tefé, Amazonas dr. b. NMW 65040, lectotype, sex not determined, 163 mm TL (body in lateral view, specimen preserved in EtOH), Brazil, rio Guaporé, Amazonas dr. c. MCP 45262 (WCNR06.090600), male, 366 mm TL, non-type (body in lateral and dorsal view, specimen fixed in formalin and preserved in EtOH); d. MCP 45260 (WC02.180598), female, 305 mm TL, non-type (body in lateral view; specimen fixed in formalin and preserved in EtOH); Brazil, rio Solimões-Japurá confluence, Amazonas dr. Note the extreme sexual dimorphism in caudal-filament length. Scale bars = 5mm.

Fig. 18. Collection records for Brachyhypopomus brevirostris (circles). Precise locality of the lectotype is not known. Elevation data refers to altitude above mean sea level (see Fig. 2 for legend).