A new genus has been erected,
Rhinotocinclus, (2022) with the type species
of Parotocinclus longirostris Garavello,
1988. Abstract: A new genus of Hypopopomatinae
armored catfish is described from the northern portions
of South America, namely the Amazon, Orinoco and Guianan
coastal drainages. The new genus is diagnosed from
all remaining hypoptopomatines by having the canal
cheek plate on the ventral surface of the head posteriorly
elongated and contacting the cleithrum, in addition
to other features that distinguish the new genus from
specific genera. Five new species are described and
18 species currently allocated in Parotocinclus,
Hisonotus, and Curculionichthys
are transferred to the new genus and rediagnosed.
Parotocinclus amazonensis and P. aripuanensis
are considered junior synonyms of P. britskii.
The secondary sexual dimorphism of the members of
the new genus is detailed and illustrated. Morphological
characters are used to delimit four phenotypic groups
of species that might have phylogenetic significance,
which still have to be properly tested. A key to the
species is offered and diagnoses, illustrations, and
distribution maps are provided for all species (Reis
& Lehmann 2022).
Description: Rhinotocinclus bockmanni
is distinguished from all congeners, except for R.
dani, R. hera, R. pentakelis,
R. marginalis n. sp., and R. loxochelis
n. sp. by having the dominant colour pattern formed
by dark bars on body well separated and distinct (vs.
dominant colour pattern formed by wide dark bars partially
coalesced or closed together, or formed by a dark
stripe from the snout tip, through the eye and extending
to end of caudal peduncle); having two separate light
lines from snout tip diverging to each nostril (vs.
light lines on snout absent, Y- or V-shaped); and
by having teeth with yellow cusps (vs. cusps brown
or light ochre). Rhinotocinclus bockmanni is
further distinguished from R. britskii, R.
kwarup, R. eppleyi, R. longirostris,
R. polyochrus, R. variola, R.
yaka, R. discolor, R. isabelae,
and R. pilosus by lacking an adipose fin
(vs. adipose fin present). Rhinotocinclus bockmanni
is further distinguished from congeners, except R.
dani, R. pentakelis, R. marginalis
n. sp., and R. loxochelis n. sp., by having
small platelets at adipose-fin position (vs. small
platelets absent). Rhinotocinclus bockmanni
is distinguished from R. dani, R. hera,
R. pentakelis, R. marginalis n.
sp., and R. loxochelis n. sp. by having a
triangular dark spot at the dorsal-fin membrane (vs.
dorsal-fin dark spot absent), and by lacking or having
a very inconspicuous dark bar 2 on body (vs. bar 2
present and conspicuous) (Reis
& Lehmann 2022).
Etymology: Rhinotocinclus masc.,
from the Greek (Rhinos), beak, snout and Otocinclus,
a genus of Hypoptopomatinae, in allusion to the conspicuous
and elegant snout of most of its species. The specific
name is for Flávio A. Bockmann, in appreciation
for his guidance and his contributions to the knowledge
of Neotropical catfishes. Remarks:
Most online searches at the moment (2022) will still
give you the old genus name of Hisonotus bockmanni.
Lower and middle Rio Tapajós basin, including
the Rio Teles Pires in the state of Pará, Brazil.
Type locality: Brazil, Pará
State, Jacareacanga Municipality, sandbank at Rio
Cururu, tributary to Rio Teles Pires, tributary to
Rio Tapajós, 08°53’42.2”S 57°14’27.8”W,
140 m asl.
Carvalho, M. and A.
Datovo, 2012. A new species of cascudinho
of the genus Hisonotus (Siluriformes: Loricariidae:
Hypoptopomatinae) from the Upper Rio Tapajós
Basin, Brazil. Copeia 2012(2):266-275
Reis RE, Lehmann A. P. A new genus of armored
catfish (Siluriformes: Loricariidae) from the Greater
Amazon, with a review of the species and description
of five new species. Neotrop Ichthyol. 2022.