Morphology Data of Hypostomus robertsoni
Identification keys
Abnormalities
Main Ref. Dias, A.C. and C.H. Zawadzki, 2021
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs
Different appearance
Different colors
Remarks

Descriptive characteristics of juvenile and adult

Striking features
Body shape lateral
Cross section
Dorsal head profile
Type of eyes
Type of mouth/snout
Position of mouth
Type of scales
Diagnosis

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 spots); 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 on keels); differs from H. nematopterus by lacking elongate dorsal-fin ray (vs. extremely elongate dorsal-fin ray); differs from its congeners of the H. auroguttatus super-group alatus, albopunctatus, arecuta, faveolus, francisci, krishnamurtii, luteus, luteomaculatus, margaritifer, meleagris, microstomus, multidens, regani, roseopunctatus, scabriceps, strigaticeps, tietensis, variipictus by having dark blotches on a clear background (vs. pale spots or vermiculations on a darker background), from asperatus, brevicauda, johnii, melanephelis, nigropunctatus, uruguayensis by having faded dark blotches similar to or slightly larger than eye diameter on trunk and fins (vs. similar to eye pupil), from denticulatus, 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), from brevis, fluviatilis, goyazensis, topavae by having parieto-supraoccipital and predorsal region flat (vs. predorsal region high and convex in frontal view), from denticulatus, freirei, kuarup, latirostris, mutucae, paulinus, ternetzi by having tooth number less than 46 on each premaxillary or dentary (vs. more than 50), from agna, isbrueckeri, luetkeni by having a single predorsal plate bordering parieto-supraoccipital (vs. 2-3 plates in luetkeni and 3 agna, isbrueckeri), from guajupia by having conspicuous blotches or marks on body and fins (vs. lacking conspicuous blotches or marks), from heraldoi by having pectoral-fin spine length smaller than pelvic-fin unbranched ray (vs. larger than), from nigromaculatus by having pectoral-fin spine slightly curved, with diameter almost homogeneous along its length (vs. curved club-shaped pectoral-fin spine), from wuchereri by having abdomen plated in specimens about 100 mm SL (vs. abdomen mostly naked in specimens up to 150 mm SL), from garmani, lima by having triangular-shaped caudal peduncle, its lateral surface straigth (vs. oval-shaped caudal peduncle, its lateral surface convex), from guajupia by having abdominal area mostly naked, larger specimens with transverse row of platelets in cleithral region and medially along abdomen (vs. abdominal area densely plated, from

pectoral girdle to anus), from hermanni by lacking or with inconspicuous dark (faded brown) blotches on body and fins (vs. usually having conspicuous black blotches), and by having truncate caudal fin (vs. emarginate) (Ref. 124595).

Ease of Identification

Meristic characteristics of Hypostomus robertsoni

Lateral Lines Interrupted: No
Scales on lateral line
Pored lateral line scales
Scales in lateral series
Scale rows above lateral line
Scale rows below lateral line
Scales around caudal peduncle
Barbels
Gill clefts (sharks/rays only)
Gill rakers
on lower limb
on upper limb
total
Vertebrae
preanal
total

Fins

Dorsal fin(s)

Attributes
Fins number
Finlets No. Dorsal   
Ventral  
Spines total
Soft-rays total
Adipose fin

Caudal fin

Attributes

Anal fin(s)

Fins number
Spines total
Soft-rays total

Paired fins

Pectoral Attributes  
Spines     
Soft-rays   
Pelvics Attributes  
Position    
Spines     
Soft-rays   
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
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cfm script by eagbayani, 17.10.00, php script by rolavides, 13/03/08 ,  last modified by sortiz, 06.27.17