Kronichthys

Pereira, Edson H. L. & Reis, Roberto E., 2017, Morphology-based phylogeny of the suckermouth armored catfishes, with emphasis on the Neoplecostominae (Teleostei: Siluriformes: Loricariidae), Zootaxa 4264 (1), pp. 1-104 : 73

Genus Kronichthys Miranda Ribeiro, 1908

Kronichthys Miranda Ribeiro, 1908: [27th unnumbered page] . Type species: Kronichthys subteres Miranda Ribeiro, 1908 . Type by monotypy.

Included species. Kronichthys heylandi (Boulenger, 1900) ; K. lacerta (Nichols, 1919) ; K. subteres Miranda Ribeiro, 1908; and Kronichthys M.

Diagnosis. Kronichthys is diagnosed by the following exclusive synapomorphies:

Autopalatine strongly curved in its posterior half (Char. 58.1), dorsal process of hyomandibula anterior to dorsal articular condyle very short (Char. 70.1), ventromesial process of unbranched pelvic-fin ray distinctly pointed (Char. 205.1), snout distinctly rectangular in dorsal view (Char. 225.1), and with four series of paired prenasal plates (Char. 234.3). Non-exclusive synapomorphies include: Mesethmoid ventral condyle very close to anterior tip of mesethmoid (Char. 5.1), accessory flange in first epibranchial long (Char. 41.2), tooth series of dentaries form angle smaller than 90 degrees and form two parallel sections mesially (Char. 61.2), mesial crest on anterodorsal portion of hyomandibula absent (Char. 75.0), dorsal opening of preopercle laterosensory canal without laminar expansion (Char. 96.0), laterosensory canal of preopercle restricted to its posterior portion (Char. 97.1), anterior margin of preopercle long, reaching close to quadrate articular condyle (Char. 101.0), cheek canal plate bent with ventral expansion directed mesially (Char. 109.1), 31–33 free centra after complex centrum (Char. 119.0), neural spine of sixth centrum elongate and horizontally rectangular (Char. 123.3), eight bifid neural spines (Char. 124.5), eighth vertebral centrum with wide and short neural spine (Char. 126.1), 9–11 pairs of pleural ribs (Char. 132.0), transverse processes of second dorsal-fin pterygiophore directed anteriorly (Char. 139.2), connecting bone articulating to distal expansion of sixth centrum rib (Char. 145.1), odontodes on ventral surface of pectoral-fin spine sharply pointed (Char. 169.0), posterior margin of pectoral-fin spine with serrations in both juveniles and adults (Char. 170.0), posterior margin pectoral fin distinctly rounded (Char. 174.0), anterior processes of basipterygium fused to each other, turning anterior portion of basipterygium into wide lamina (Char. 185.1), anterior portion of basipterygium lacking paired fenestrae (Char. 191.0), unbranched pelvic-fin ray lacking skin fold on dorsal surface (Char. 199.0), odontodes on ventral surface of unbranched pelvic-fin ray oriented mesially (Char. 201.1), odontodes on ventral surface of unbranched pelvic-fin ray sharply pointed (Char. 203.1), first analfin pterygiophore with wide lateral process for articulation of lateral plates (Char. 212.1), and hypurapophysis forming distinctly narrow process directed anteriorly (Char. 219.2).

Comparisons. Kronichthys species are distinguished from all other neoplecostomines by having the premaxilla and dentary tooth series strongly curved mesially in such a way that the mesial portion of the tooth series are turned and run parallel to each other and by having the odontodes on the pelvic-fin spine turned mesially (vs. odontodes aligned with the pelvic-fin spine axis). Additionally, adult Kronichthys have a somewhat rectangular head and narrow, elongate body shape (vs. a broad, rounded head and body narrowing progressively towards the caudal peduncle).

Geographic distribution. Kronichthys species occur in the costal river basins between Paranaguá Bay in Paraná State and Guanabara Bay in Rio de Janeiro State, Brazil .