This species is distinguished from the species of the super-group H. cochliodon 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°; differs from the species of the super-group H. hemiurus by having round dark blotches (vs. somewhat horizontally elongate dark blotches); differs from the species of the super-group H. plecostomus by lacking rows of odontodes on keels along lateral series of plates (vs. with moderate to well-developed rows of odontodes); differs from H. nematopterusa by lacking elongate dorsal-fin ray (vs. extremely elongate dorsal-fin ray); differs from its congeners of the H. auroguttatus super-group by having dark spots or blotches on a clear background (vs. pale spots or vermiculations on a darker background); differs from asperatus, brevicauda, johnii, leucophaeus, nigropunctatus, uruguayensis by having large dark blotches, similar to or larger than eye diameter on trunk and fins (vs. small spots, similar to or smaller than eye pupil diameter); differs from atropinnis, denticulatus, freirei, goyazensis, iheringii, macrops, latirostris, ternetzi by having parieto-supraoccipital and predorsal region flat (vs. parieto-supraoccipital medially raised and with raised parallel keels on predorsal region); differs from brevis, garmani, goyazensis, lima, topavae ( by having parieto-supraoccipital and predorsal region flat (vs. predorsal region high and convex in frontal view); differs from denticulatus, jaguar, latirostris, mutucae, paulinus, ternetzi by having tooth number less than 46 on each premaxillary or dentary (vs. more than 50); differs from agna, angipinnatus, latifrons, luetkeni by having a single predorsal plate bordering parieto-supraoccipital (vs. two to three plates); differs from perdido by having bicuspid teeth (vs. unicuspid teeth); differs from peckoltoides by having dark large blotches on body and fins (vs. wide dark transverse bars on body and bands on fins); differs from guajupia by having conspicuous blotches or marks on body and fins (vs. lacking conspicuous blotches or marks);

differs from heraldo by having pectoral-fin spine length smaller than pelvic-fin unbranched ray (vs. larger than); differs from nigromaculatus by lacking a curved club-shaped pectoral-fin spine (vs. curved club-shaped pectoral-fin spine); differs from wuchereri by having abdomen plated in specimens about 100 mm SL (vs. abdomen mostly naked in specimens up to 150 mm SL); differs from yuka by lacking hypertrophied odontodes on laterals of trunk (vs. mature males with hypertrophied odontods on laterals of trunk); differs from garmani, guajupia by the compressed caudal peduncle, almost triangular shaped, lateral surface of caudal peduncle straight (vs. oval-shaped caudal peduncle, lateral surface of caudal peduncle convex) (Ref. 124595)..

differs from species of the super-group H. cochliodon by having large dark is distinguished from the 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 is distinguished from the species of the supergroup 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) (Ref. 124595).