ANNOTATED LIST OF THE SPECIES 317 Dorsal sealation lacking; mouth large while that of Higenmannia is minute; unlike in that the jaws are more nearly equal; dorsal profile of the head concave (Higenmannia convex).
No caudal fin or dorsal filament; snout not projecting; eye without a free margin; back naked to a point over the last third of the anal fin; mouth terminal, large, the maxillary very oblique; mandible rounded or pointed; mandibular teeth in four regular rows across the front, none on the lateral rami; teeth of the upper jaw in about five less regular series.
441. RHABDOLICHOPS LONGICAUDATUS Eigenmann and Allen, sp. noy. Plate XVI, figs. 3 and 4 15436,1,497mm.,totallength,type,Iquitos,Morris,1922.
15810,1,840mm.,totallength,paratype,Iquitos,Allen,September,1920. 15996, 3, 400-415 mm. to end of anal fin, paratypes, Iquitos, Morris, 1922. Of the five specimens one appears to be more nearly normally proportioned, and it is designated as the type. The others all have enormously exaggerated tails, which are tumid and greatly prolonged. It would seem impossible for such a species, even in a streamline-conscious era, to exist, carrying a tail of the dimensions of no. 15810, for instance; impossible for it to survive in waters teeming with rapacious fishes among which even conservative Gymnotids so frequently suffer mutilations.
Description of the type:
Head 14; depth 12; A. 254; length to the end of the anal fin 317 mm., tail 180 mm.; snout 3.5 in the head; eye 6.36; interorbital 6; depth of head equal to half its length; anus under the vertical from the eye; origin of anal fin behind the vertical from the base of the pectoral fin; pectoral 0.7 in the length of the head; upper profile of the head depressed, the lower strongly convex; mouth large, terminal; gape slightly oblique when the mouth is closed, the maxillary nearly vertical when the mouth is open; free edge of the maxillary nearly equal to the snout. Scales of the lateral line large, those above and below it smaller; back naked, the naked area extending down to the lateral line at its origin, becoming more constricted caudally; about 130 scales in the lateral line forward from the end of the anal fin.
Back dusky, sides light, no definite markings.
As stated above, only the type seems to have a normal tail, unless we may consider the hypertrophy of the majority asa normal. Of the other four specimens the tail is unusual, if not indeed abnormal. In two of these the tail has been broken in life, and the ends are lost, either in the digestive tracts of fishes, or incidentally to the collecting procedure. Of the two remaining, one has a pointed tail 432 mm. long, of the usual shape. Without the appendage the specimen, 15810, is 408 mm. in length, that is, the tail exceeds the owner in length; the anal has 237 rays. In the fourth specimen the tail appears broken at a point about 210 mm. beyond the anal, and is continued as a bag about 40 mm. long, covered with thin scales. The end of the bag is blunt, suggesting a second injury. Total length of this specimen is 670 mm., 420 to the end of the anal fin, tail 250 mm.
318 FISHES OF WESTERN SOUTH AMERICA Similar to Higenmannia troscheli, differing in the characters mentioned in the description of the genus, and the tumid tail. Subfamily: APTERONOTINAE SternarchinaeEigenmann,1912,Mem.CarnegieMus.,V,437. Gymnotids with caudal fin, tail short; orbital margin not free; a dorsal filament present; teeth in patches on one or both jaws. KEY TO THE GENERA OF THE SUBFAMILY APTERONOTINAE a.Snoutproduced,theeyebehindthemiddleofthehead;mouthsmall;teethinbothjaws b. Snout decurved; mouth minute............................STERNARCHORHYNCHUS bb.Snoutstraight ¢G Mouth Warge. 2007722) ei nee eee eee STURNARCHORHAMPEUS Cen.Mouth:minutesas1Mibis5.Seereynnscients(extralimital)ORTHOSTERNARCHUS aa. Snout produced or not; mouth large; eye in anterior part of the head, or the rictus under the eye d. Lower jaw normal, included e. Teeth in both jaws normal f.Backscaled g.Mouthvariable,itsanglelittleifanyinfrontoftheeye..APTERONOTUS gg. Mouth small, its angle under posterior nostril. ..STERNARCHELLA ff.Backnaked,mouthsmall;scalesabovelaterallinesubcircular..POROTERGUS ee,Noteeth,orteethconfinedtomandible;backnaked;scalesabovethelateralline MUChHhietherstiemelO12:seeeeeysisleeateeeanSTERNARCHOGITON eee. Teeth strong, fixed, many on tumid, everted jaws; back naked; scales above the lateral Jine. much higher than long. .2..:2.../..:2.!..%: OEDEMOGNATHUS dd.Lowerjawheavy,projectingbeyondtheupper,bothonthesidesandinfront;noteeth; ouvelke Aymilae stories hai inne suas be abn coae ma sbeurccsm ann oo!
\ DONTOSTERNARCHUS Genus 176: STERNARCHORHYNCHUS Castelnau SternarchorhynchusCastelnau,1855,Anim.Amér.Sud,Poiss.,91,95; Eigenmann and Eigenmann, 1891, Proc. U. S. Nat. Mus., XIV, 62; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, HI, 449; Eigenmann,1912,Mem.CarnegieMus.,Vi,4375 Ellis,19183,Mem.CarnegieMus.,VI,140. Rhamphosternarchus Ginther, 1870, Cat. Fish. Brit. Mus., VI, 140. Type: Sternarchorhynchus miilleri Castelnau = Sternarchus oxyrhynchus Miller and Troschel Guianas to Peruvian Amazon With caudal fin; gape very small; patches of teeth on both jaws; head medium, conical; snout long, tubular, and somewhat decurved; no free orbital margin; fontanels present; caudal fin small, terminal, fan-shaped, slightly scaled at base; body compressed and slightly elongate, becoming very slender in caudal region; scales eycloid; lateral line complete; anal long, widest in the middle, narrowing toward both extremities.
442. STERNARCHORHYNCHUS OXYRHYNCHUS (Miiller and Troschel) SternarchusoxyrhynchusMillerandTroschel,1848,inSchomburgk,Reisen,IIT,640; Miiller and Troschel, 1849, Horae Ichth., III, 16, pl. ii, figs. 1 and 2; Kkaup,1856,Cat.Apod.,127;
ANNOTATED LIST OF THE SPECIES 319 Giinther, 1870, Cat. Fish. Brit. Mus., VIII, 4; Boulenger,1898,Trans.Zool.Soc.London,XIV,427,Jurua. SternarchorhynchusoxyrhynchusFKigenmannandKigenmann,1891,Proc.U.S.Nat.Mus.,XIV,62; EigenmannandWard,1905,Proce.Wash.Acad.Sei.,VIL,167; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 449; Eigenmann,1912,Mem.CarnegieMus.,V,437; Ellis, 1913, Mem. Carnegie Mus., VI, 140. SternarchorhynchusmiillertCastelnau,1855,Anim.Amér.Sud,Poiss,95. SternarchusmormyrusSteindachner,1868,Sitzb.KIX.Akad.Wiss.Wien,5,pl.i,fig.3; Ginther, 1870, Cat. Fish. Brit. Mus., VIII, 4, Peruvian Amazon; Eigenmann and Eigenmann, 1891, Proc. U.S. Nat. Mus., XIV, 62. Sternarchorhynchus mormyrus Eigenmann and Ward, 1905, Proc. Wash. Acad. Sci., VII, 167, Peruvian Amazon; Eigenmann,1910,Rept.PrincetonUniv.Exped.Patagonia,IIT,449. Sternarchus(Rhamphosternarchus)curvirostrisBoulenger,1887,Proc.Zool.Soe.London,282,pl. xxiv, two specimens, Canelos.
SternarchorhynchuscurvirostrisEigenmannandEigenmann,1891,Proc.U.S.Nat.Mus.,XIV,62; Eigenmann and Ward, 1905, Proc. Wash. Acad. Sei., VII, 167; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 449. Guianas and Upper Amazon 15991, 1, about 310 mm., Iquitos, Morris, 1922. Genus 177: STERNARCHORHAMPHUS Eigenmann and Ward SternarchorhamphusEigenmannandWard,1905,Proc.Wash.Acad.Sci.,VII,165; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 449; Ellis, 1913, Mem. Carnegie Mus., VI, 142. Type: Sternarchus miilleri Stemndachner Peruvian Amazons to Para Fontanels present; caudal fin; snout produced, straight; mouth large; body very elongate and compressed; maximum depth at or just behind the pectoral fins; head medium to moderately large, pointed, produced; gape rather straight; small conical teeth above and below; eyes small and covered; scales cycloid; lateral line straight and complete; anal long, widest forward, tapering caudally; caudal fin very small.
443. STERNARCHORHAMPHUS MACROSTOMUS (QGiinther) SternarchusmacrostomaGiinther,1870,Cat.Fish.Brit.Mus.,VIIT,4. Rhamphosternarchus macrostomus Cope, 1878, Proc. Amer. Phil. Soc., XVII, 682, Xeberos and Peruvian Amazon.
SternarchorhynchusmacrostomaEFigenmannandEigenmann,1891,Proc.U.S.Nat.Mus.,XIV,62. SternarchorhamphusmacrostomusEigenmannandWard,1905,Proc.Wash.Acad.Sci.,VII,166, Peruvian Amazon; EKigenmann,1910,Rept.PrincetonUniv.Exped.Patagonia,III,449; Ellis, 1913, Mem. Carnegie Mus., VI, 144. Peruvian Amazon
320 FISHES OF WESTERN SOUTH AMERICA 444. STERNARCHORHAMPHUS MULLERI (Steindachner) Sternarchus(Rhamphosternarchus)miillerdStemdachner,1881(1882),Denksch.Kix.Akad.Wiss. Wien, XLIV, 18, pl. xviu, fig. 4.
Sternarchorhynchusmiller?EigenmannandEigenmann,1891,Proc.U.S.Nat.Mus.,XIV,62. Sternarchorhamphus millert Eigenmann and Ward, 1905, Proc. Wash. Acad. Sci., VII, 166; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 449; Ellis, 1913, Mem. Carnegie Mus., VI, 142, fig. 10; Fowler, 1939 (1940), Proc. Acad. Nat. Sei. Phila., XCI, 276, two, 358 and 400 mm., Contamana.
From the Lower Amazon to the Ucayali Genus 178: APTERONOTUS Lacépéde Anteronotus Lacépede, 1800, Hist. Nat. Poiss., Il, 208, passan = albifrons; Jordan, 1917, The Genera of Fishes, Stanford Univ. Publ., Part I, 56. SternarchusBlochandSchneider,1801,Syst.Ichth.,497,albifrons; Cuvier, 1817, Régne Anim., II, 237; Eigenmann and EKigenmann, 1891, Proc. U.S. Nat. Mus., XTV. 61; Figenmann and Ward, 1905, Proc. Wash. Acad. Sci., VII, 161; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 448: Higenmann, 1912, Mem. Carnegie Mus., V, 438; Ellis, 1913, Mem. Carnegie Mus., VI, 145. Type: Gymnotus albifrons Linnaeus Amazons, British Guiana to Paraguay and Rio Parana Fontanels present; caudal present, and small; both jaws with patches of teeth; mouth large, gape long and horizontal, lower jaw included within the upper, two or more rows of teeth in the upper, two rows on lower; snout short and not tubular; eyes without a free orbital margin; back scaled, head naked, scales cycloid; pectorals not equal to more than half the depth; origin of anal at or before vertical from gill. opening, of uniform depth, not reaching caudal. KEY TO THE SPECIES OF THE GENUS APTERONOTUS a. Seales small, 11 to 16 rows above the lateral line b.Snoutmoreorlesspointed,interorbitalwidthmorethan5inthehead c.Distanceofeyetosnouttwicethedistancefromeyetoupperangleofgill-opening asessoaDesseatssawccaBteneseatheNOSeasSecsRGCoaCAINathoieeanas ce.Distanceofeyetosnoutlessthanthedistanceoftheeyetoupperangleofthegill- OPENING:
age atest wcroh eee ch iru < ererancea com arya:
Cue et eet nner leptorhynchus bb. Snout blunt, interorbital width less than 4.75 in head d. Rather slim; flesh color to light grey, entirely covered with fine chromatophores BORieekaeheroneeteMeeseee)SietS,reAONEaeresHONEARita&GoWeiosGthasemani dd. Robust; ground-color dead black; 2 white bands encircling body, one at base of caudal,theothernearendofanal;frontalareamoreorlesswhite....albifrons aa. Scales above lateral line large, not to exceed eight rows.................0 0.000005 bonaparti 445. APTERONOTUS ALBIFRONS (Linnaeus) Gymnotus albifrons Linnaeus, 1766, Syst. Nat., ed. xi, 428. SternarchusalbifronsBlochandSchneider,1801,Syst.Ichth.,497,pl.xciv; Castelnau, 1855, Anim. Amér. Sud, Poiss., 91, pl. xlv, fig. 1; Cope, 1878, Proc. Amer. Phil. Soe., XVII, 682, Peruvian Amazon;
ANNOTATED LIST OF THE SPECIES 321 Boulenger,1887,Proce.Zool.Soe.London,282,Canelos; Eigenmann and Kigenmann, 1891, Proc. U. 8. Nat. Mus., XIV, 61; Higenmann and Ward, 1905, Proc. Wash. Acad. Sei., VII, 162; EKigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, IIT, 448; Figenmann, 1912, Mem. Carnegie Mus., V, 439; Ellis, 1913, Mem. Carnegie Mus., VI, 148.
Sternarchus maximilliant Castelnau, 1855, Anim. Amér. Sud, Poiss., 93, pl. xlv, fig. 4, Urubamba river.
Orinoco, Guianas, Amazons, Rios Paraguay and Paranda 15432, 1, 300 mm., Iquitos, Morris, 1922.
446. AprTRRONOTUS LEPTORHYNCHUS Ellis SternarchusleptorhynchusEllis,1912,inEigenmann,Mem.CarnegieMus.,V,439; Ellis, 1913, Mem. Carnegie Mus., VI, 147, pl. xxu, fig. 4; Eigenmann, 1922, Mem. Carnegie Mus., IX, 175, pl. xxxv, fig. 1. Colombia to Peru and British Guiana 15434, 1, over 340 mm. (probably 100 mm. lost), Iquitos, Morris, 1922. Snout much elongated; gape also very long; anus beneath vertical limb of preopercle.
Depth 1.16 in the head length; eye equidistant between snout and third fifth of the pectoral; distance between the eye and the upper angle of the gill-opening about 1.22 in the snout.
It is a question whether this specimen may not be identical specifically with A. anas rather than with the more remote Guiana types. In the type of A. leptorhynchus 260 mm. in length the eye is nearer the tip of the snout than to the gillopening, but in other characters such as depth it resembles the present species. There is a reasonable expectation of finding it here. 447. AprpRoNoTUS ANAS Eigenmann and Allen, sp. nov. Plate XV, fig. 1 15433, 1, 365 mm., type, Iquitos, Morris, 1922. Head 3.7; depth 2 in the head; eye nearer tip of pectoral than to tip of snout by one-seventh the length of the snout; distance between the eye and the upper angle of the gill-opening less than one-half the length of the snout; about 11 scales above the lateral line; origin of anal under the middle of the gill-opening; caudal peduncle short (normal?), blackish; a light, median dorsal line; caudal light in the middle, dark above and below.
Near A. leptorhynchus Ellis, and differing most strikingly in the shape and proportions of the head, the eye being conspicuously farther back than in the type of leptorhynchus.
448. APTERONOTUS BONAPARTII Castelnau SternarchusbonapartiiCastelnau,1855,Anim.Amér.Sud,Poiss.,92,pl.xlv,fig.2,Ucayali; Giinther, 1870, Cat. Fish. Brit. Mus., VIII, 3; Cope, 1878, Proc. Amer. Phil. Soe., XVII, 682, Peruvian Amazon;
322 FISHES OF WESTERN SOUTH AMERICA Eigenmann and Eigenmann, 1891, Proc. U. 8. Nat. Mus., XIV, 62; Eigenmann and Ward, 1905, Proc. Wash. Acad. Sci., VII, 163; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, HI, 448; Ellis, 1913, Mem. Carnegie Mus., VI, 149, fig. 13; Fowler, 1915, Copeia, no. 15, Peruvian Amazon; Fowler, 1939 (1940), Proc. Acad. Nat. Sei. Phila., XCI, 277, one specimen, 308 mm., Contamana.
Lower and middle Amazons, Rio Ucayali 449, APTERONOTUS HASEMANTI Ellis Sternarchus hasemani Ellis, 1913, Mem. Carnegie Mus., VI, 147, pl. xxi, fig. 1; Pearson, 1937a, Proc. Cal. Acad. Sei., (4), XXIII, 92, Tingo de Pauca and Paipay, upper Maranon.
Known from Santarem and from upper Maranon; Iquitos. 15425, 2, 294 and 318 mm., Iquitos, Morris, 1922. Genus 179: STERNARCHELLA Eigenmann and Ward Sternarchella Eigenmann and Ward, 1905, Proc. Wash. Acad. Sci., VII, 163; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, HI, 448; Ellis, 1913, Mem. Carnegie Mus., VI, 150. Type: Sternarchus schotti Steindachner Barro do Rio Negro to Peru Short-snouted; gape short, not reaching beyond posterior naris; eyes small, covered, nearer tip of snout than to end of the opercle; small teeth in both jaws; scales moderately large and cycloid.
450. STERNARCHELLA SCHOTTI (Steindachner) Sternarchus schotti Steindachner, 1868, Sitzb. Kk. Akad. Wiss. Wien, LVIII, 4, pl. i, figs. 1 and 2; Giinther, 1870, Cat. Fish. Brit. Mus., VIII, 3; Cope, 1878, Proc. Amer. Phil. Soc., XVII, 682, Peruvian Amazon; Eigenmann and Eigenmann, 1891, Proc. U. 8S. Nat. Mus., XIV, 61. SternarchellaschotttKigenmannandWard,1905,Proc.Wash.Acad.Sci.,VII,164; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, IIT, 448; Ellis, 1913, Mem. Carnegie Mus., VI, 151, fig. 14; Fowler, 1939 (1940), Proc. Acad. Nat. Sei. Phila., XCI, 277, one, 190 mm., Contamana. Solimoes and Marafion systems, and Ucayali river Genus 180: POROTERGUS Ellis Porotergus Ellis, 1912, in Kigenmann, Mem. Carnegie Mus., V, 440; Ellis, 1913, Mem. Carnegie Mus., VI, 152. Type: Porotergus gymnotus Ellis Peruvian Amazon, Santarem, Rio Essequibo May be known for the want of scales along the back to a point more or less beyond the origin of the dorsal filament; scales along the lateral line of large size;
ANNOTATED LIST OF THE SPECIES 323 gape long, nearly reaching the vertical from the eye; teeth in both jaws; in other respects much as A pteronotus and other members of the subfamily. KEY TO THE SPECIES OF THE GENUS POROTERGUS a. Mouth inferior, minute; rictus between the nostrils; snout very blunt, about 4 in the head So 5 Bothd Slo O05 qo CHojolg Ulm oEO 5 Sicotrizebls geutsmelasyie Lisp algeitel isin) ute “o) a), ees yoicst,sus)csshsits}.elt ofish's eis)isu eves gumbeli aa.Mouthterminal b. Mouth minute, similar to that of Sternopygus macrurus; rictus under anterior nostril; snout pointed, 3 in the head oo , terminalis bb.Mouthlarger,therictusbehindtheposteriornostril;snout2.75intheheadgymnotus (extralimital) Fic.35.TheUpperAmazonflowssoswiftlybelowthePongodeManserichethatlaunchesmake wayupstreamwithsomedifficulty.Numerousislandssuchasthisoccur. 451. PoroTERGUS GIMBELI Ellis Porotergus gimbeli Ellis (in Eigenmann), 1912, Mem. Carnegie Mus., V, 441; Ellis, 1913, Mem. Carnegie Mus., VI, 15+. Guiana, Amazons Peru to Para 15435,1,95mm.,Iquitos,Allen,September,1920. Very similar to Sternarchogiton nattereri, but with strong teeth in both jaws. Hitherto known only from the types, four specimens from Para and British Guiana, collected by Haseman and Ellis respectively.
324 FISHES OF WESTERN SOUTH AMERICA 452. PoROTERGUS TERMINALIS Eigenmann and Allen, sp. nov. 15994, 1, 240 mm., type, Iquitos, Morris, 1922.
15720,2,225and299mm.,paratypes,Iquitos,Allen,September,1920. Similar in form to the type species P. gymnotus, and in many characters not unlike P. gimbel/; differs from the short-snouted gimbeli in the terminal position of the mouth, much longer head and greater depth; more resembles gimbeli in the number of anal rays, having many more than gymnotus; teeth much stronger than in either.
Head 5.5-5.8; depth 5.33-5.66; A. 179-184; lateral line about 70; origin of anal under emarginate part of the opercle; anus a little behind the vertical from the eye; profile straight, eye placed high; depth of head equals its length less the opercle; interorbital width 4.5-5.5 in the length of the head to the end of the opercular spine; snout 3.2-3.3; mouth small, terminal; maxillary nearly vertical; teeth strong; in two series in each jaw; gill-opening not equal to the snout; scales on the sides, from the lateral line to the anal muscles, large, and from the lateral line upward much smaller, circular toward the naked back; naked part of the back extending down to the lateral line in front, much more narrowly restricted farther back; the pectoral fin equal to the length of the head less the opercle; back dusky, other parts colorless.
Named for the distal position of the mouth.
Genus 181: STERNARCHOGITON Eigenmann and Ward SternarchogitonEigenmannandWard,1905,Proc.Wash.Acad.Sci.,VII,164; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 448; Ellis, 1913, Mem. Carnegie Mus., VI, 155.
Type: Sternarchus natterert Steindachner Middle Amazon to Peru Sometimes a few teeth appear in a single series in the lower Jaw, sometimes on the sides only, sometimes none; no teeth on the upper jaw; the head much compressed, the lower jaw grooved into the upper; back naked; scales above the lateral line much higher than long.
KEY TO THE SPECIES OF THE GENUS STERNARCHOGITON a. Head smaller, about 12 in the length, eve larger, snout smaller, about 3.5... .. .....-natterert aa. Head larger, about 9, eve 7 in snout.......... Me reg iy sere Aap hse ta ees lt _...porcinum 453. STERNARCHOGITON NATTERERI (Steindachner) Sternarchus natlerert Steindachner, 1868, Sitzb. Kk. Akad. Wiss. Wien, LVIII, 3, pl. u, fig. 1, Barro doRioNegro; Giinther, 1870, Cat. Fish. Brit. Mus., VIII, 3; Eigenmann and Higenmann, 1891, Proc. U. 8. Nat. Mus., XIV, 62. Sternarchogitonnatlerer?EigenmannandWard,1905,Proc.Wash.Acad.Sci.,VII,165; Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 448; Ellis, 1913, Mem. Carnegie Mus., VI, 155.