75
Endoparasites of anurans in the seven cities national park
Neotropical Helminthology, Vol. 19, Nº1, jan - jun 2025
Neotropical Helminthology
Neotropical Helminthology, 2025, vol. 19 (1), 75-84
ORIGINAL ARTICLE / ARTÍCULO ORIGINAL
A NEW SPECIES OF
RHINOXENOIDES
(DACTYLOGYRIDAE)
PARASITIZING
TRIPORTHEUS ANGULATUS
(SPIX & AGASSIZ, 1829)
(CHARACIFORMES) FROM THE JURUÁ RIVER BASIN, BRAZIL
UNA NUEVA ESPECIE DE
RHINOXENOIDES
(DACTYLOGYRIDAE)
QUE PARASITA A
TRIPORTHEUS ANGULATUS
(SPIX & AGASSIZ, 1829)
(CHARACIFORMES) EN LA CUENCA DEL RÍO JURUÁ, BRASIL
Simone Chinicz Cohen
1
; Williane Maria de Oliveira Martins
2
& Marcia Cristina Nascimento Justo
1*
ISSN Versión Impresa 2218-6425 ISSN Versión Electrónica 1995-1403
DOI: https://dx.doi.org/10.62429/rnh20251911914
Universidad Nacional
Federico Villarreal
Volume 19, Number 1 (jan - jun) 2025
Este artículo es publicado por la revista Neotropical Helminthology de la Facultad de Ciencias Naturales y Matemática, Universidad Nacional Federico
Villarreal, Lima, Perú auspiciado por la Asociación Peruana de Helmintología e Invertebrados Af nes (APHIA). Este es un artículo de acceso abierto,
distribuido bajo los términos de la licencia Creative Commons Atribución 4.0 Internacional (CC BY 4.0) [https:// creativecommons.org/licenses/by/4.0/
deed.es] que permite el uso, distribución y reproducción en cualquier medio, siempre que la obra original sea debidamente citada de su fuente original.
ABSTRACT
A new species of
Rhinoxenoides
was described parasitizing the gill f laments of neotropical triportheid f shes. T e new
species was described from
Triportheus angulatus
(Spix & Agassiz, 1829)
from the Juruá River, State of Acre, Brazil.
Rhinoxenoides cruzeirensis
n. sp. resembles
Rhinoxenoides horacioschneideri
Santos Neto, Costa, Soares & Domingues,
2018, mainly by presenting a coiled male copulatory organ (MCO) with clockwise rings; accessory piece with articulation
process extending within the coils to the base of MCO; dorsal anchor with well-developed superf cial root, and dorsal
bar absent. However, it dif ers from this by number of the coils of the MCO; accessory piece formed by a straight piece
that expands in the middle, where it folds over itself; ventral bar short and robust; dorsal anchor with a well-developed
superf cial root twice as long as the deep root, with a small wing-shaped extension in the distal portion.
Keywords:
Dactylogyridae – Neotropical Region – Parasites of f shes –
Rhinoxenoides
– South America – Triportheidae
1
Laboratório de Helmintos Parasitos de Peixes, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz – Fiocruz, Avenida Brasil,
4365, Rio de Janeiro, RJ 21040-900, Brasil. scohen@ioc.f ocruz.br / marciajusto@ioc.f ocruz.br
2
Laboratório de Biologia Geral do Instituto Federal de Acre (IFAC), Campus Cruzeiro do Sul, Estrada da Apadec nº1192,
Bairro Nova Olinda, CEP: 69980-000, Cruzeiro do Sul, Acre, Brazil. williane.martins@ifac.edu.br
* Corresponding author: marciajusto@ioc.f ocruz.br
Simone Chinicz Cohen:
https://orcid.org/0000-0001-8204-336X
Williane Maria de Oliveira Martins:
https://orcid.org/0000-0002-0684-3389
Marcia Cristina Nascimento Justo:
https://orcid.org/0000-0003-2078-7587
76
Neotropical Helminthology, Vol. 19, Nº1, jan - jun 2025
Chinicz Cohen
et al.
RESUMEN
Se describió una nueva especie de
Rhinoxenoides
parasitando los flamentos branquiales de peces triportheidos
neotropicales. La nueva especie fue descrita de
Triportheus angulatus
(Spix & Agassiz, 1829)
del río Juruá, estado de
Acre, Brasil.
Rhinoxenoides cruzeirensis
n. sp. se asemeja a
Rhinoxenoides horacioschneideri
Santos Neto, Costa, Soares &
Domingues, 2018, principalmente por presentar organo copulatorio masculino (OCM) con anillos espirales en sentido
horario; pieza accesoria con proceso de articulación que se extiende dentro de espirales hasta la base de OCM; ancla
dorsal con raíz superfcial bien desarrollada y barra dorsal ausente. Pero se diferencia de este por el número de espirales de
la OCM; pieza accesoria formada por una pieza recta que se expande en el centro, donde se pliega sobre sí misma; barra
ventral corta y robusta; ancla dorsal con una raíz superfcial bien desarrollada dos veces más larga que la raíz profunda
con una pequeña extensión en forma de ala en la porción distal.
Palabras clave:
Dactylogyridae – Parásitos de peces – Región neotropical –
Rhinoxenoides
– Sudamérica – Triportheidae
INTRODUCTION
Te Amazon biome boasts the largest hydrographic
system in the world and the largest freshwater reserve,
containing around 20% of the global freshwater, and is
considered one of the richest ecosystems on the planet.
Te Amazon hydrographic region represents 49.29% of
the Brazilian territory, covering all or part of the states
of Acre, Amazonas, Roraima, Rondônia, Pará, Amapá,
Maranhão, Tocantins, and Mato Grosso (Tosta &
Coutinho 2015; IBGE, 2019; Silva & Bampi, 2019).
Parasite diversity in Amazonian fshes is likely
underestimated, given the region’s rich ichthyofauna
and high levels of endemism. Tis unique combination
supports a remarkable variety of helminth species (Luque
et al
., 2017). Understanding fsh parasite diversity could
be an important tool for conserving global biodiversity
(Luque
et al
., 2017).
Te Juruá River Basin belongs to the great Amazon Basin
and is located between the states of Acre and Amazonas.
It is drained by extensive rivers in a general southwest-
north-east direction, with rivers of great importance
throughout its course, such as the Juruá River, which
rises in the Peruvian Andes and fows into the Solimões
River. Tis river is one of the main tributaries of the right
bank of the Amazon River and is considered one of the
most winding in the world, forming huge food grids
and thousands of lakes (ACRE, 2012; Costa
et al
., 2012;
Sousa & Oliveira, 2016, Mota da Silva, 2020).
Although there is signifcant diversity of helminth species
recorded in the Amazon, knowledge about parasite richness
remains incomplete in certain areas. Most research focuses
on the Central and Eastern Amazon, while the southwestern
Amazon has received limited attention. Studies in the Juruá
River basin have primarily documented parasitic fauna in
aquaculture systems, leading to a substantial knowledge
gap regarding the biodiversity of parasites associated with
fsh in natural systems in this southwestern Amazon region
(Virgilio
et al
., 2021).
Recent research on the Juruá River has identifed fve species
of monopisthocotylan, including three
Cosmetocleithrum
spp. parasitizing the catfsh
Oxydoras niger
(Valenciennes,
1821) in the Juruá River:
Cosmetocleithrum basicomplexum
Silva, Meneses, Martins, Cohen, Costa & Justo, 2023,
Cosmetocleithrum confusus
Kritsky, Tatcher & Boeger,
1986,
Cosmetocleithrum sacciforme
Silva, Meneses,
Martins, Cohen, Costa & Justo, 2023, and
Unibarra
juruaensis
Justo, Martins & Cohen, 2023 and
Unibarra
paranoplatensis
(Suriano & Incorvaia, 1995) parasitizing
Pimelodus blochii
Valenciennes, 1840 (Justo
et al
., 2023;
Silva
et al.,
2023).
Within the order Characiformes, Triportheidae includes
fve genera and 23 species (Froese & Pauly, 2024), among
which
Triportheus angulatus
(Spix & Agassiz, 1829), a
benthopelagic freshwater fsh, distributed in the Amazon
River basin in South America and exclusive to the
Neotropical Region (Malabarba, 2004, Froese & Pauly,
2024). Tese species are exploited by subsistence fshing
and have become an alternative source of fsh since the
natural stocks of other commercially important fsh
species in the Amazon have declined over time (Cajado
et al
., 2023).
To date, 29 species of Monopisthocotyla have been
described in South America from Triportheidae hosts,
with the majority of these species classifed under the
genus
Anacanthorus
Mizelle & Price, 1965 (see Table).
77
New species of
Rhinoxenoides
Neotropical Helminthology, Vol. 19, Nº1, jan - jun 2025
Table 1.
Species of Monopisthocotyla reported in South America from
Triportheus
spp. hosts.
MONOPISTHOCOTLAHOSTCOUNTRYREFERENCE
Anacanthorus acuminatus
Kritsky, Boeger & Van
Every, 1992
T. albus, T. angulatus, T.
elongatus
BRKritsky
et al.
(1992); Moreira
et al.
(2017)
Anacanthorus alatus
Kritsky, Boeger & Van Every,
1992
T. albus, T. elongatus
BRKritsky
et al
. (1992)
Anacanthorus andersoni
Kritsky, Boeger & Van Every,
1992
T. angulatus
BRKritsky
et al
. (1992)
Anacanthorus bellus
Kritsky, Boeger & Van Every,
1992
T. albus, T. elongatus,
Triportheus
sp.
BRKritsky
et al.
(1992)
Anacanthorus calophallus
Kritsky, Boeger & Van
Every, 1992
T. elongatus
BRKritsky
et al.
(1992)
Anacanthorus carinatus
Kritsky, Boeger & Van Every,
1992
T. angulatus
BRKritsky
et al
. (1992)
Anacanthorus chaunophallus
Kritsky, Boeger & Van
Every, 1992
T. angulatus
BRKritsky
et al.
(1992); Moreira
et al.
(2017)
Anacanthorus chelophorus
Kritsky, Boeger & Van
Every, 1992
T. angulatus, Triportheus
sp.BRKritsky
et al.
(1992); Moreira
et al.
(2017)
Anacanthorus cornutus
Kritsky, Boeger & Van Every,
1992
T. angulatus
BRKritsky
et al.
(1992)
Anacanthorus euryphallus
Kritsky, Boeger & Van
Every, 1992
T. albus, T. angulatus, T.
elongatus
BRKritsky
et al.
(1992); Moreira
et al.
(2017)
Anacanthorus formosus
Kritsky, Boeger & Van Every,
1992
T. elongatus, Triportheus
sp.BRKritsky
et al.
(1992)
Anacanthorus furculus
Kritsky, Boeger & Van Every,
1992
T. elongatus, T. rotundatus
BRKritsky
et al.
(1992); Santos & Tavares-Dias
(2017)
Anacanthorus glyptophallus
Kritsky, Boeger & Van
Every, 1992
T. angulatus
BRKritsky
et al.
(1992)
Anacanthorus lygophallus
Kritsky, Boeger & Van
Every, 1992
T. angulatus
BRKritsky
et al.
(1992); Moreira
et al.
(2017)
(Continúa Table 1)
78
Neotropical Helminthology, Vol. 19, Nº1, jan - jun 2025
Chinicz Cohen
et al.
Anacanthorus nanus
Kritsky, Boeger & Van Every,
1992
T. angulatus
BRKritsky
et al.
(1992)
Anacanthorus pelorophallus
Kritsky, Boeger & Van
Every, 1992
T. elongatus
BRKritsky
et al
. (1992)
Anacanthorus pithophallus
Kritsky, Boeger & Van
Every, 1992
T. angulatus
,
T. curtus
,
T.
rotundatus
BRKritsky
et al
. (1992); Oliveira
et al.
(2016);
Moreira
et al.
(2017); Santos & Tavares-Dias
(2017)
Anacanthorus quinqueramus
Kritsky, Boeger & Van
Every, 1992
T. albus, T. elongatus,
Triportheus
sp
.
BRKritsky
et al.
(1992)
Anacanthorus ramulosus
Kritsky, Boeger & Van Every,
1992
T. albus, T. elongatus
BRKritsky
et al.
(1992)
Anacanthorus strongylophallus
Kritsky, Boeger & Van
Every, 1992
T. elongatus
BRKritsky
et al.
(1992)
Anacanthorus tricornis
Kritsky, Boeger & Van Every,
1992
T. angulatus, T. elongatus
BRKritsky
et al.
(1992)
Ancistrohaptor falcatum
Agarwal & Kritsky, 1998
T. elongatus
BRAgarwal & Kritsky (1998)
Ancistrohaptor falciferum
Agarwal & Kritsky, 1998
T. albus, T. angulatus, T.
elongatus, Triportheus
sp.
BRAgarwal & Kritsky (1998); Moreira
et al
.
(2017)
Ancistrohaptor falcunculum
Agarwal & Kritsky, 1998
T. albus, T. angulatus, T.
elongatus
BRAgarwal & Kritsky (1998); Moreira
et al.
(2017)
Ancistrohaptor forfcata
Diniz, Sousa, Yamada &
Yamada, 2025
T. signatus
BRDiniz
et al
. (2025)
Jainus iquitensi
s Morey, Viana, Chota & Chero, 2025
T. angulatus
PEMorey
et al
. (2025)
Jainus loretoensis
Morey, Viana, Chota & Chero,
2025
T. angulatus
PEMorey
et al.
(2025)
Jainus sardinae
Morey, Viana, Chota & Chero, 2025
T. angulatus
PEMorey
et a
l. (2025)
Rhinoxenus anaclaudiae
Domingues & Boeger, 2005
T. angulatus, T. nematurus,
Triportheus
sp.
BRDomingues & Boeger (2005); Moreira
et al
.
(2017)
(Continúa Table 1)
79
New species of
Rhinoxenoides
Neotropical Helminthology, Vol. 19, Nº1, jan - jun 2025
In continuation of the studies carried out in the Juruá
River Basin in Brazil, aiming to describe the fauna of
helminths parasitizing freshwater fsh, a new species of
Rhinoxenoides
Santos Neto, Costa, Soares & Domingues,
2018 was found infesting the gills of
T. angulatus
. Te new
species described here enhances our understanding of the
diversity of monopisthocotylan parasites in triportheid
fshes, as well as ofering valuable insights into the
region’s biodiversity, and underscoring the importance of
expanding research across the Amazon basin.
MATERIAL AND METHODS
In January 2024, two specimens of
T. angulatus
were
captured with gill nets and a hook and line from Juruá
River, Acre, Brazil (7°40
′
34.1
″
S, 72°39
′
39.5
″
W) (Fig.
1). All collections obtained environmental licensing
through the Biodiversity Authorization and Information
System (SISBIO, 396871-1). Te gills were removed and
placed in vials containing hot water (~65ºC) and they
were then vigorously shaken to detach the parasites from
the gill flaments. Absolute ethanol was added to reach
a concentration of 70%. Te parasites were collected
from the sediment and gill arches in the laboratory with
the aid of a stereoscopic microscope. Te specimens
were mounted unstained in Hoyer’s medium for the
study of the sclerotized parts. Photomicrographs and
drawings were taken using a Zeiss® Axioskop microscope
micrographic system, with a diferential interference
contrast (DIC) apparatus and an Olympus BX 41
microscope with phase contrast, equipped with a camera
lucida. All measurements are in micrometers, and the
means are followed by the range in parentheses and by
the number of specimens measured when more than two.
Dimensions of organs and other structures represent the
greatest distance; lengths of curved or bent structures (bars
and accessory piece) represent the straight-line distances
between extreme ends. Te numbering of hook pairs
follows Mizelle & Price (1963). Holotype and paratypes
were deposited in the helminthological collection of the
Instituto Oswaldo Cruz (CHIOC).
Figure 1.
Location of the study area, Juruá River, Acre municipality of Cruzeiro do Sul, Brazil
(7°40
′
34.1
″
S, 72°39
′
39.5
″
W) Cruzeiro do Sul, Acre State, Brazil.
Ethical aspects
: All applicable institutional, national and
international guidelines for the care and use of animals
were followed.
RESULTS
TAXONOMY
Class Monopisthocotyla Brabec, Salomaki, Kolısko,
Scholz & Kuchta, 2023
Order Dactylogyridea Bychowsky, 1937
Dactylogyridae Bychowsky, 1933
Rhinoxenoides
Santos Neto, Costa, Soares & Domingues,
2018
Rhinoxenoides
cruzeirensis
n. sp. (Fig. 2 A-G)
Type-host:
Triportheus angulatus
(Spix & Agassiz, 1829)
(Characiformes: Triportheidae).
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Neotropical Helminthology, Vol. 19, Nº1, jan - jun 2025
Chinicz Cohen
et al.
Site in host:
Gill lamellae.
Type-locality:
Juruá River, municipality of Cruzeiro do
Sul, Acre, Brazil (7°40
′
34.1
″
S, 72°39
′
39.5
″
W).
Parasitological indices:
Total number of hosts: 2;
number of infected hosts: 1; total number of parasites:
11.
Deposited material:
Holotype (CHIOC 40615a);
Paratypes (CHIOC 40615b-i).
Etymology:
Te specifc name is dedicated to the
municipality of Cruzeiro do Sul, in the state of Acre,
Brazil, where the parasite was recovered.
Description (Based on 11 specimens, mounted in
Hoyer’s medium). Body fusiform, elongated, comprising
cephalic region, trunk, and haptor. Tegument thin,
smooth. Body 509 (415–625; n = 10) long, 74 (60–85;
n = 11) wide at the level of germarium. Anterior region
with four cephalic lobes well developed, two terminal,
two bilateral; three pairs of head organs; cephalic
glands indistinct. Two pairs of eyespots, posterior pair
larger and closer together than anterior pair; accessory
granules absent (Fig. 2A). Pharynx spherical 20 (18–22;
n = 6) in diameter. Esophagus short. Two intestinal
ceca confuent posteriorly to testis, lacking diverticula.
Gonads intercecal, tandem. Germarium ventral to testis,
74 (70–80; n = 4) long. Vagina and vaginal canal slightly
sclerotized; vaginal aperture sinistroventral. Seminal
receptacle spherical. Mehlis’ gland, uterus, oviduct, and
ootype not observed. Egg 72 long by 45 wide (n = 1).
Vitellaria extends throughout the trunk, except in areas of
other reproductive organs. Prostatic reservoir elongated
posterior to male copulatory organ (MCO), 41 (40–42;
n = 3) long. Copulatory complex comprising MCO and
accessory piece. Coiled MCO with 1½ clockwise rings,
17 (15–20; n = 5) proximal ring diameter; accessory piece
formed by a straight piece that expands in the middle,
where it folds over itself; in the proximal portion it
articulates with the base of the MCO, 40 (35–44; n = 4)
long, through a copulatory ligament (Fig. 2B). Peduncle
inconspicuous. Haptor subtriangular, 65 (52–73; n = 8)
wide (Fig. 2A). Ventral bar short and wide, 19 (15–22; n
= 9) long (Fig. 2C). Dorsal bar absent. Ventral and dorsal
anchor dissimilar in size and shape. Ventral anchor with
superfcial root elongated, well developed; deep root short,
rounded; evenly curved shaft, point not passing from the
level of the type of superfcial root, 69 (65–72; n = 16)
long, base 28 (24–31; n = 13) (Fig. 2D). Dorsal anchor
with a well-developed superfcial root, slender, twice the
size of the deep root and a small wing-shaped extension
in the distal portion; deep root elongated, rounded at the
tip; straight shaft, short point hook-shaped, 55 (53–58; n
= 17) long, base 10 (8–11; n = 7) (Fig. 2E). Hooks similar
in shape, shank divided into two subunits, distal part of
shank infated; flamentous hook (FH) loop extending
close to the beginning of shank dilation, erect thumb,
curved long shaft, delicate point. Hook pairs 1 and 5, 16
(15–16; n = 4) long (Fig 2G), and hook pairs 2, 3, 4, 6,
and 7, 21 (20–22; n = 8) long (Fig. 2F).
Remarks:
Te new species was allocated in
Rhinoxenoides
as it shares characteristics of the genus, such as MCO
formed by a coiled tube with clockwise rings articulated to
the accessory piece by copulatory ligament; dorsal anchor
with superfcial root twice the size of the deep root; and by
the absence of dorsal bar.
Rhinoxenoides cruzeirensis
n. sp.
is similar to
Rhinoxenoides horacioschneideri
Santos Neto,
Costa, Soares & Domingues, 2018, the only species of
the genus, by presenting a well-developed ventral anchor
with a superfcial truncated root; prostatic reservoir
elongated, not divided into regions; vagina sinistral;
coiled MCO with clockwise rings; accessory piece with
articulation process extending within coils to the base
of MCO; dorsal anchor with well-developed superfcial
root comprising three times the total length, and dorsal
bar with enlarged ends. Te new species difers from
R
.
horacioschneideri
by presenting a coiled MCO with 1½
clockwise rings; accessory piece formed by a straight
piece that expands slightly at its center, where it bends
into the shape of an elbow (2½ coils; comprising variable
distal sheath in
R
.
horacioschneideri
); ventral bar short
and robust (V-shaped in
R
.
horacioschneideri
); dorsal
anchor with a well-developed superfcial root twice as
long as the deep root and a small wing-shaped extension
in the distal portion (three times longer than the deep
root; small wing-shaped extension in the distal portion
absent in
R
.
horacioschneideri
) and by the hook size (1-3
and 5 smaller than the others in
R
.
horacioschneideri
).
In the original description, the authors stated that the
species present the dorsal anchor with superfcial root
twice the size of deep root, but in the original drawing
the superfcial root is shown as three times as long as deep
root, feature confrmed by examining the type material
deposited in the Helminthological Collection of Oswaldo
Cruz Institute CHIOC 39025a (holotype); 39025b-c
(paratypes); 39026 (paratype), and 39027a-d (vouchers).
DISCUSSION
Rhinoxenoides
Santos Neto, Costa, Soares & Domingues,
2018 was erected by Santos-Neto
et al.
(2018) to
accommodate
R. horacioschneideri
described from
Acestrorhynchus falcatus
(Bloch, 1794). It is characterized
81
New species of
Rhinoxenoides
Neotropical Helminthology, Vol. 19, Nº1, jan - jun 2025
Figure 2.
Rhinoxenoides cruzeirensis
n. sp. from
Triportheus angulatus
. A, Total, ventral view (composite); B, Copulatory
complex, ventral view; C, Ventral bar; D, Ventral anchor; E, Dorsal anchor; F, Hook pairs 2-4,6,7. G, Hook pairs 1,5.
Scale bars: A, 100 µm, B, 20 µm, C, F, G, 10 µm, D, E, 30 µm.
by the morphology of copulatory complex, composed
of a coiled tube with clockwise rings articulated to
the accessory piece by copulatory ligament; by the
morphology of haptoral sclerites as dorsal anchor with
the superfcial root twice as long as the deep root;
straight shaft, curved point; and by the absence of
dorsal bar (Santos-Neto et al., 2018). Te monotypic
genus presents shared characteristics, such as the
presence of a copulatory ligament and dorsal anchors
with a straight long shaft and absence of a dorsal bar,
with
Rhinoxenus
Kritsky, Boeger & Tatcher, 1988,
but difer by the coiled MCO with counterclockwise
coils, absence of superfcial and deep roots in both pairs
of anchors, and dorsal anchor with elongate, straight
82
Neotropical Helminthology, Vol. 19, Nº1, jan - jun 2025
Chinicz Cohen
et al.
shaft in
Rhinoxenus
.
Protorhinoxenus
Domingues &
Boeger, 2002, a genus closely related to
Rhinoxenus
was proposed by Domingues & Boeger (2002).
Both genera share morphological features such as a
coiled MCO with counterclockwise coils, absence of
superfcial and deep roots in both pairs of anchors,
and dorsal anchors with elongated and straight shafts.
Rhinoxenus
and
Rhinoxenoides
share the character of the
absence of a dorsal bar, difering from
Protorhinoxenus
in this feature. According to Santos-Neto
et al
. (2018),
the absence of dorsal bar could be interpreted as an
independent secondary loss in
Rhinoxenoides
and
Rhinoxenus
, or its absence could be shared by the three
genera as a synapomorphy with secondary acquisition
in
Protorhinoxenus
. Tese authors proposed a cladistic
hypothesis, in which species of
Protorhinoxenus
,
Rhinoxenoides
, and
Rhinoxenus
share the presence of a
copulatory ligament and dorsal anchors with a straight
long shaft. Tese features are also observed in the new
species of
Rhinoxenoides
proposed herein. Te authors
stated that species of
Protorhinoxenus
,
Rhinoxenoides
,
and
Rhinoxenus
seem to be exclusively found infecting
characiform fshes from South America. According
to our results, by proposing another species of
Rhinoxenoides
parasitizing a characiform fsh belonging
to Triportheidae, while the previously reported species
of the genus was collected from Acestrorhynchidae,
propose that members of these three other genera are
not restricted to members of one host family within
Characiformes. Te fnding shows that the parasite
faunas of fshes need to be further characterized through
additional sampling for monopisthocotylan of species
of all characiform families, and that cladistics studies
are necessary, to elucidate
host-parasite relationships in
the freshwater fshes of the Neotropical Region.
Author contributions: CRediT (Contributor Roles
Taxonomy)
SCC =
Simone Chinicz Cohen
WMOM =
Williane Maria de Oliveira Martins
MCNJ =
Marcia Cristina Nascimento Justo
Conceptualization:
SCC
Data curation:
SCC, WMOM, MCNJ
Formal Analysis:
SCC, WMOM, MCNJ
Funding acquisition:
SCC
Investigation:
SCC, WMOM, MCNJ
Methodology:
WMOM, MCNJ
Project administration:
SCC
Resources:
SCC, WMOM, MCNJ
Software:
MCNJ
Supervision:
SCC
Validation:
SCC, WMOM, MCNJ
Visualization:
SCC, WMOM, MCNJ
Writing – original draft:
SCC, WMOM, MCNJ
Writing – review & editing:
SCC, MCNJ
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84
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Chinicz Cohen
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Received February 10, 2025.
Accepted April 10, 2025.