Hypostomus hermanni ( Ihering, 1905 )

Dias, Angelica Corrêa & Zawadzki, Cláudio Henrique, 2021, Hypostomus hermanni redescription and a new species of Hypostomus (Siluriformes: Loricariidae) from Upper Paraná River basin, Brazil, Neotropical Ichthyology (e 200093) 19 (2), pp. 1-24 : 4-11

Hypostomus hermanni ( Ihering, 1905)

( Figs. 1–3 ; 9 ; Tabs. 1–2)

Plecostomus hermanni : Ihering, 1905:560 (original description; type-locality: Piracicaba River, São Paulo, Brazil). — Gosline, 1947:124 (brief description; partim).

Hypostomus hermanni : Isbrücker, 1980:24 (validation of Hypostomus hermanni ( Ihering, 1905)) . — Burgess, 1989:431 (checklist). — Gómez, Chebez, 1996:64 (checklist). — Isbrücker, 2001:28–31 (checklist). — Isbrücker, 2002:19 (revision of Loricariidae ). —Weber, 2003:358 (checklist). —López et al., 2003:51 (checklist). —Armbruster, 2004:79 (phylogeny). —Menni, 2004:81 (checklist). — Ferraris, 2007:254 (checklist). —Galves et al., 2007:256 (checklist). —Langeani et al., 2007:188 (checklist). —Bueno et al., 2012:245 (check list cytogenetic data). —Bueno et al., 2013,104 (cytogenetics). —Oliveira et al., 2013:265 (checklist). —Paiva et al., 2013:571-578 (allozymes; fig. 1c, p. 572). —Bueno et al., 2014:3 (cytogenetics). — Frota et al., 2016:6 (checklist). —Silva et al., 2016:12 (phylogeny; fig. 7d, p. 14). —Zawadzki et al., 2016:264 (reference to color pattern and comparative material). —Zawadzki et al., 2018:257 (diagnosis from Hypostomus latirostris and from H. renestoi ). — Dias, Zawadzki, 2018:394 (identification key; fig. 6, p. 401). —Zawadzki et al., 2019:240 (cited as additional specimens examined). —Queiroz et al., 2020:9 (phylogenetic relationship).

Diagnosis. Hypostomus hermanni is distinguished from the species of the super-group H. cochliodon Kner, 1854 by having viliform teeth and dentaries usually angled more than 100° (vs. spoon- or shovel-shaped teeth and dentary rami angled to each other up to 80°; from the species of the super-group H. hemiurus (Eigenmann, 1912) by having round dark blotches (vs. somewhat horizontally elongate dark blotches); from the species of the super-group H. plecostomus ( Ihering, 1905) by lacking rows of odontodes on keels along lateral series of plates (vs. with moderate to well-developed rows of odontodes on keels); from H. nematopterus Isbrücker & Nijssen, 1984 by lacking elongate dorsal-fin ray (vs. extremely elongate dorsal-fin ray). From the congeners of the H. auroguttatus Kner, 1854 super-group Hypostomus hermanni is diagnosed from H. alatus Castelnau, 1855 , H. albopunctatus (Regan, 1908) , H. arecuta Cardoso, Almirón, Casciotta, Aichino, Lizarralde & Montoya-Burgos, 2012 , H. faveolus Zawadzki, Birindelli & Lima, 2008 , H. fluviatilis (Schubart, 1964) , H. francisci (Lütken, 1874) , H. krishnamurtii Zawadzki, Penido & Lucinda, 2020 , H. luteomaculatus (Devincenzi, 1942) , H. luteus (Godoy, 1980) , H. margaritifer (Regan, 1908) , H. meleagris (Marini, Nichols & LaMonte, 1933) , H. microstomus Weber, 1987 , H. multidens Jerep, Shibatta & Zawadzki, 2007 , H. regani ( Ihering, 1905) , H. roseopunctatus Reis, Weber & Malabarba, 1990 , H. strigaticeps (Regan, 1908) , H. tietensis ( Ihering, 1905) and H. variipictus (Ihering, 1911) by having dark spots or blotches on a clear background (vs. pale spots or vermiculations on a darker background); from H. asperatus Castelnau, 1855 , H. brevicauda (Günther, 1864) , H. johnii (Steindachner, 1877) , H. leucophaeus Zanata & Pitanga, 2016 , H. nigropunctatus Garavello, Britski & Zawadzki, 2012 , H. renestoi Zawadzki, da Silva & Troy, 2018 and H. uruguayensis Reis, Weber & Malabarba, 1990 by having large dark blotches, that is, similar to or larger than eye diameter on trunk and fins (vs. small spots, similar to or smaller than eye pupil diameter); from H. atropinnis (Eigenmann & Eigenmann, 1890) , H. denticulatus Zawadzki, Weber & Pavanelli, 2008 , H. freirei Penido, Pessali & Zawadzki, 2021 , H. goyazensis (Regan, 1908) , H. iheringii (Regan, 1908) , H. macrops (Eigenmann & Eigenmann, 1890) , H. latirostris (Regan, 1904) and H. ternetzi (Boulenger, 1895) by having parieto-supraoccipital and predorsal region flat (vs. parieto-supraoccipital medially raised and with raised parallel keels on predorsal region); from H. brevis (Nichols, 1919) , H. garmani (Regan, 1904) , H. goyazensis (Regan, 1908) , H. lima (Lütken, 1874) and H. topavae (Godoy, 1969) by having parieto-supraoccipital and predorsal region flat (vs. predorsal region high and convex in frontal view); from H. denticulatus , H. jaguar Zanata, Sardeiro & Zawadzki, 2013 , H. latirostris , H. mutucae Knaack, 1999 , H. paulinus ( Ihering, 1905) and H. ternetzi by having tooth number less than 46 on each premaxillary or dentary (vs. more than 50); from H. agna (Miranda Ribeiro, 1907) , H. angipinnatus (Leege, 1922) , H. isbrueckeri Reis, Weber & Malabarba, 1990 , H. latifrons Weber, 1986 , H. luetkeni (Steindachner, 1877) and by having a single predorsal plate bordering parieto-supraoccipital (vs. two to three plates); from and H. perdido Zawadzki, Tencatt & Froehlich, 2014 by having bicuspid teeth (vs. unicuspid teeth); from H. peckoltoides Zawadzki, Weber & Pavanelli, 2010 by having dark large blotches on body and fins (vs. wide dark transverse bars on body and bands on fins); from H. guajupia Penido, Pessali & Zawadzki, 2021 by having conspicuous blotches or marks on body and fins (vs. lacking conspicuous blotches or marks); from H. heraldoi Zawadzki, Weber & Pavanelli, 2008 by having pectoral-fin spine length smaller than pelvic-fin unbranched ray (vs. larger than); from H. nigromaculatus (Schubart, 1964) by lacking curved club-shaped pectoral-fin spine (vs. curved club-shaped pectoral-fin spine); H. wuchereri (Günther, 1864) by having abdomen plated in specimens about 100 mm SL (vs. abdomen mostly naked in specimens up to 150 mm SL); from H. yaku Martins, Langeani & Zawadzki, 2014 by lacking hypertrophied odontodes on laterals of trunk (vs. mature males with hypertrophied odontods on laterals of trunk) and from H. garmani and H. guajupia by compressed caudal peduncle, almost triangular shaped, lateral surface of caudal peduncle straight (vs. oval-shaped caudal peduncle, lateral surface of caudal peduncle convex).

Description. Morphometric and meristic data are presented in Tabs. 1–2. Head broad and stout. Body width at cleithral region greater than head depth and approximately equal to head length. Snout and anterior profile of head rounded in dorsal view. Snout rising at approximately 40° from horizontal in lateral profile. Dorsal profile convex and sloped upward from snout tip to interorbital region, convex again from that point to dorsal-fin origin; sloped downward from dorsal-fin origin to region just anterior of dorsal procurrent caudal-fin rays, then elevating again to caudal-fin insertion. Caudal peduncle deep, strongly compressed laterally and slightly flattened ventrally. Eye comparatively moderate to large, dorsolaterally positioned. Interorbital space straight in frontal view; orbit barely raised. Mesethmoid region with inconspicuous median ridge on dorsal surface of snout to nares. Pair of low rounded ridges on the dorsolateral surface of head, from lateral margins of nares to anterodorsal margin of eyes, and from that longitudinally through superior portion of compound pterotic. Cheek plates usually lacking developed odontodes even in larger specimens. Exposed surface of opercle large, its horizontal length usually slightly smaller than eye diameter. Parieto-supraoccipital generally flat anteriorly; with posterior weak median ridge; with short posterior process; and posteriorly bordered by large single plate. Dorsal and lateral surfaces of head and body covered with dermal plates, except for small naked patch on tip of snout and at dorsal-fin base. Dermal plates with slightly enlarged odontodes on posterior border. Predorsal region flat, lacking ridges. Body lateral surface with five longitudinal series of plates. Dorsal series of plates dorsally flattened from dorsal-fin base origin to caudal-fin origin. Mid-dorsal and median series lacking keels. Median series bearing complete lateral-line pores. Mid-ventral series with first four to five plates bent, without keels to caudal peduncle. Ventral series gently bent.

Mouth short to moderate, dentary width approximately 15–28% of cleithral width. Lips round, short to moderate, lower lip length 16.2–30.3% of lower lip width. Outer edge of upper lip with odontodes. Lower lip not reaching gill openings line. Lower lip inner surface covered with numerous small papillae, larger proximally to dentary. Maxillary barbel moderate in size, shorter than orbital diameter. Median buccal papilla moderately developed. Villiform bicuspid teeth. Teeth moderate to robust, with elongated main cusp and smaller and pointed lateral cusp. Teeth crown ventrally arched in lateral view. Intermandibular tooth row angle about 120°.

Lower surface of head mostly plated except beneath lower lip. Abdomen largely plated except moderate to large areas around pelvic-fin insertions and around urogenital openings. Dorsal fin II,7; moderate in size; its distal border slightly to moderately convex; when adpressed usually reaching azygous plate of adipose fin; spine flexible. Adipose-fin spine inflexible and well developed, slightly curved and posteriorly oriented, with distal tip of spine usually reaching first dorsal procurrent caudal-fin ray. Pectoral fin I,6, its distal border straight; pectoral-fin spine inflexible, slightly curved with rounded tip, and usually with distally slightly developed hooked odontodes, especially in larger specimens (about 150 mm SL, NUP 16526); when adpressed reaching from one third to half pelvic-fin spine. Pelvic fin i,5 with branched rays slightly decreasing in size posteriorly; its distal border straight to slightly convex. Pelvic-fin spine flexible, curved inward; when adpressed surpassing anal-fin insertion. Anal fin i,4; when adpressed, distal tip of posterior rays reaching sixth to seventh plate posterior to its origin. Caudal fin i,7,7,i; truncate to slightly emarginate.

Coloration in alcohol. Dorsal ground color of body and fins grayish brown. Body dorsolaterally covered with dark blotches; ventral region of body clearer and lacking blotches. Numerous blotches on head, slightly smaller than eye pupil diameter, equally set. Blotches on trunk and fins moderately spaced to each other, usually slightly larger than eye pupil. In some populations blotches on trunk and fins can be equal to eye diameter or even slightly larger ( Fig. 1 ). In some specimens blotches inconspicuous towards caudal peduncle. Dorsal, pectoral, pelvic, and caudal fins with one series of blotches on each interradial membrane. Adult specimens with a narrow black line bordering distal margins of dorsal and caudal fins. Dorsal fin with longitudinal inconspicuous dark stripe anteriorly margining branched rays. Blotches on caudal fin transversely aligned to form four to five bands. Usually all spines and unbranched-fin rays with blotches or dark marks, except anal-fin unbranched ray. In specimens from the Piracicaba River, blotches on dorsal fin sometimes blurred or mottled. In specimens from other localities blotches usually sharply defined and very conspicuous. blotches on anal fin more faded than on other fins.

Coloration in life. The same pattern which was described for alcohol preserved specimens, but with greenish background color tan and blotches darker ( Fig. 3 ).

Sexual dimorphism. Not found.

Geographical distribution and type-locality. Hypostomus hermanni was described from the type-locality Piracicaba. The species is known from the Piracicaba River ( Fig. 4 ), and the Tietê River basin in the state of São Paulo, Southeastern Brazil. Additionally , the species is herein also recorded in the Paraná River main channel and three of its left tributaries, Paranapanema , Ivaí , and Piquiri basin, in the state of Paraná, Southern Brazil ( Fig. 7 ). As specimens of H. hermanni are mainly found in shallow to moderate shallow running waters, if Ihering (1911) referred the type-locality Piracicaba River as the Piracicaba city, the most probable collecting spot of the holotype was the Salto de Piracicaba, a single rocky rapid stretch in the Piracicaba River at Piracicaba city ( Fig. 4 ) .

Material examined. All from Brazil. All from Upper Paraná River basin: Tietê River basin : BMNH 1905.6 .9.5, 1, 201.8 mm SL, holotype of H. hermanni ( Ihering, 1905) . LIRP 11440 , 15 , 56.1–111.4 mm SL . LIRP 11464 , 3 , 106.1 – 124.6 mm SL . MZUSP 1977 , 1, 168.1 mm SL . MZUSP 1978 , 16 , 64.6–84.1 mm SL . MZUSP 2115 , 2 , 150.6 – 183.1 mm SL . MZUSP 2116 , 2 , 135.8 – 195.1 mm SL . MZUSP 2132 , 1, 120.8 mm SL . MZUSP 3748 , 2 , 64.3–77.5 mm SL . MZUSP 10680 , 4 , 52.2–75.8 mm SL . MZUSP 14859 , 4 , 52.2–75.8 mm SL . MZUSP 14860 , 1, 166.8 mm SL . MZUSP 22371 , 1, 111.4 mm SL . MZUSP 24539 , 2 , 181.7 – 187.1 mm SL . MZUSP 24768 , 1, 217.4 mm SL . MZUSP 53801 , 7 , 125.3 – 166.8 mm SL . MZUSP 87135 , 1, 137.9 mm SL . MZUSP 87150 , 1 , 92.2 mm SL . MZUSP 87712 , 4 , 56.2–104.5 mm SL . MZUSP 87713 , 6 , 78.5 – 152,5 mm SL . MZUSP 87738 , 1 , 191.0 mm SL . MZUSP 92999 , 8 , 75.7–182.9 mm SL . MZUSP 95258 , 1, 145.1 mm SL . NUP 2563 , 4 , 146.7 – 208.4 mm SL . NUP 3996 , 10 , 50.5–156.2 mm SL . NUP 4014 , 3 , 93.9–132.4 mm SL . NUP 4791 , 12 . NUP 5406 , 3 , 94.5–125.1 mm SL . NUP 6410 , 15 , 47.5–139.2 mm SL . NUP 6432 , 19 , 50.5– 159.6 mm SL . NUP 16526 , 11 , 104.7 – 161.6 mm SL. Tibagi River basin : MZUEL 4464 , 2 , 143.4 – 155.9 mm SL . MZUEL 4474 , 3 , 127.1 –135.0 mm SL . MZUEL 4644 , 1, 171.7 mm SL . MZUEL 4663 , 1 , 87.3 mm SL . MZUEL 5528 , 6 , 94.0– 162.5 mm SL . MZUEL 6447 , 1, 109.8 mm SL . NUP 4863 , 10 , 169.0–230.0 mm SL . NUP 6403 , 5 , 146.2 – 189.9 mm SL . NUP 9826 , 4 , 149.0– 228.2 mm SL . NUP 10544 , 1, 165.5 mm SL . NUP 10994 , 1 , 37.6 mm SL . NUP 14995 , 4 , NUP 15005 , 14 , 139.0– 219.7 mm SL . NUP 17245 , 6 . NUP 17252 , 3 , 77.7–196.1 mm SL. Piquiri River basin : NUP 4927 , 4 , 142.8 – 183.6 mm SL . NUP 5584 , 2 , 116.8 – 128.9 mm SL . NUP 5585 , 1, 144.7 mm SL . NUP 5586 , 1, 128.9 mm SL . NUP 5587 , 1, 153.8 mm SL . NUP 9085 , 1 , 94.8 mm SL. Ivaí River basin : NUP 5402 , 9 , 113.2 – 181.4 mm SL . NUP 5403 , 10 , 87.4–173.3 mm SL . NUP 6409 , 21 , 104.6 – 206.3 mm SL . NUP 9806 , 1, 180.6 mm SL .

Figures

FIGURE 1 | Hypostomus hermanni, NUP 16526, topotype, 134.4 mm SL; Brazil, São Paulo State, Piracicaba, Piracicaba River, Upper Paraná River basin. Dorsal, lateral and ventral views.

FIGURE 2 | Hypostomus hermanni, BMNH 1905.6.9.5, holotype, 201.8 mm SL; Brazil, São Paulo State, Piracicaba, Piracicaba River, Upper Paraná River basin. Dorsal, lateral and ventral views.

FIGURE 3 | Hypostomus hermanni, in life. NUP 16526, topotype, 134.4 mm SL; Brazil, São Paulo State, Piracicaba, Piracicaba River, Upper Paraná River basin.

FIGURE 4 | Salto de Piracicaba, Piracicaba River, tributary of Tietê River, Upper Paraná River basin. The most probable type-locality spot of Hypostomus hermanni. Brazil, São Paulo State, Piracicaba, 22°43’15’’S 47°39’22’’W, 474 m.

FIGURE 7 | Distribution of Hypostomus hermanni (green triangle, type-locality, and orange circles) and H. robertsoni (red triangle, type-locality, and black circles) among Upper Paraná River basin. Some marks may represent more than one record.

FIGURE 9 | Hypostomus hermanni, from different sub basins in the Upper Paraná River basin. From top to bottom: NUP 16526, 134.4 mm SL, Tietê River; NUP 14995, 152.2 mm SL, Tibagi River; NUP 5584, 128.1 mm SL, Piquiri River; NUP 5402, 175.1 mm SL, Ivaí River.