187
Neotrop. Helminthol., 7(2), 2013
2013 Asociación Peruana de Helmintología e Invertebrados Afines (APHIA)
ISSN: 2218-6425 impreso / ISSN: 1995-1043 on line
ORIGINAL ARTICLE / ARTÍCULO ORIGINAL
DESCRIPTION OF QUADRIGYRUS MACHADOI (FABIO, 1983) (ACANTHOCEPHALA,
QUADRIGYRIDAE) IN NATIVE FISH OF WETLANDS ASSOCIATED WITH THE SAN JAVIER
RIVER, SANTA FE, ARGENTINA
DESCRIPCIÓN DE QUADRIGYRUS MACHADOI (FABIO, 1983) (ACANTHOCEPHALA,
QUADRIGYRIDAE) EN PECES NATIVOS DE HUMEDALES ASOCIADOS AL RIO SAN
JAVIER, SANTA FE, ARGENTINA
1 1
Silvina B. Chemes & Romina G. Brusa
Abstract
Keywords: Acanthocephala - Argentina - Hoplias malabaricus - Middle Paraná System - Pimelodus maculates -
Quadrigyrus machadoi - San Javier River.
Suggested citation: Chemes, SB & Brusa, RG. 2013. Description of Quadrigyrus machadoi (Fabio, 1983) (Acanthocephala,
Quadrigyridae) in native fish of wetlands associated with the San Javier River, Santa Fe, Argentina. Neotropical Helminthology,
vol. 7, n°2, jul-dec, pp. 187 - 194.
School of Humanities and Sciences, National University of Litoral. Ciudad Universitaria s/nº, Paraje El Pozo, S3000Z, Santa Fe, Argentina.
E-mail: schemes@fhuc.unl.edu.ar
In order to study the host-parasite interaction of native fish Middle Paraná system, Santa Fe,
Argentina, the digestive tracts of 64 specimens of Hoplias malabaricus (Pisces, Erythrinidae) and
of 70 specimens of Pimelodus maculatus (Pisces, Pimelodidae) were analyzed. These native
species are important for the economy and recreational activities of the region. The fish were
collected from two lentic environments associated with the San Javier River, Cayastá, in the
province of Santa Fe, Argentina. After dissecting the digestive tracts, parasites were detected by
stereoscopic microscopy, collected and preserved in alcohol at 70% for subsequent taxonomic
identification and description. In the intestines of both hosts, sixty-nine specimens of
Quadrigyrus machadoi (Acanthocephala, Quadrigyridae) were reported for the first time in the
Middle Paraná System in this province. The parasitic prevalence was determined for each case
(P= 20.31 %, H. malabaricus; P= 28.6 %, P. maculatus) and an extended description of the
icthyoparasite was carried out. This work broadens the geographical distribution of Q. machadoi
for both hosts and contributes to the advancement of knowledge on the icthyoparasites associated
with the regional icthyc fauna.
INTRODUCTION
Among the registers of fish parasites, the Upper
Paraná River floodplain exhibits a richness of
337 registered species (Takemoto, 2005;
Lacerda et al., 2008; Takemoto et al., 2009;
Takemoto & Lizama, 2010). In the Middle
Paraná System, although research is still
incipient, 91 taxa have already been recognized,
mostly Eucestoda and Digenea (Chemes &
Takemoto, 2011).
Among macroparasites, members of the phylum
Acanthocephala are dioecious and present a
heteroxenous life cycle, parasitizing aquatic and
terrestrial vertebrates as adults, and crustaceans
or insects as intermediate hosts. Each worm
attaches itself to the intestinal wall of its host by
means of an anterior protrusible proboscis
bearing rows of recurved spines. Larvae often
live in the mesentery, stomach, intestinal cecum,
liver and visceral cavity (Nickol, 1995; Ruppert
et al., 2004; Machado da Rocha, 2011). So far, a
total of 158 species of acanthocephala and 44
genera have been described in South America,
most of them being endemic in the neotropical
region (Amin, 2000).
The genus Quadrigyrus Van Cleave, 1920, was
initially established in Venezuela, with species
Q. torquatus parasitizing Hoplias malabaricus
(Bloch, 1794), Synbranchus marmoratus
(Bloch, 1979), Crenicichla geayi (Pellegrin,
1903), Gephyrocharax valenciae (Eigenmann,
1920) and Astyanax bimaculatus (Linnaeus,
1758) (Van Cleave, 1920). Later, another species
was described, Q. cholodkowskyi proposes by
Kostylew (1928), found in Varicorhinus segangi
Rüppell 1835, which was later changed to the
genus Acanthocephalorhynchoides Kostylew,
1941 (Diaz-Ungria & Rodrigo, 1957; Schmidt &
Hugghins, 1973). The third species, Q.
brasiliensis, was proposed by Machado Filho
(1941) as parasite of Hoplerythrinus
unitaeniatus (Spix & Agassiz, 1829) and H.
malabaricus, in Salobra, Mato Grosso (Brazil).
Schmidt & Hugghins (1973) described a new
species, Q. nickoli, which is distinguished by the
number of trunk spines, four circles of 23 to 29
spines, each of 10-20 um in length, with
dendritic roots. Q. torquatus has three or four
circles of 10 to 18 spines, each of 12 to 24 um in
length with weak bases and Q. brasiliensis has
three circles of 12 spines, each of 48 microns in
length with weak roots.
Later, Fabio (1983) described Q. machadoi in
Chemes & Brusa
Quadrigyrus machadoi in native fish from Argentina
188
Resumen
Palabras clave: Acanthocephala – Argentina - Hoplias malabaricus - Pimelodus maculatus -
Quadrigyrus machadoi - río San Javier - Sistema Paraná Medio.
Con el objeto de estudiar la interacción hospedador-parásito en peces nativos del Sistema Paraná
Medio, Santa Fe, Argentina, se analizaron los tractos digestivos de 64 ejemplares de Hoplias
malabaricus (Pisces, Erythrinidae) y 70 de Pimelodus maculatus (Pisces, Pimelodidae), especies
autóctonas de importancia económica y deportiva. Los peces fueron obtenidos de dos ambientes
leníticos asociados al río San Javier, Cayastá, Santa Fe, Argentina. Luego de la disección de los
tractos digestivos, se buscaron los parásitos bajo microscopía estereoscópica, los cuales fueron
colectados y conservados en alcohol al 70% para luego identificarlos taxonómicamente y
describirlos. En intestino de ambos hospedadores, se determinaron 69 ejemplares de Quadrigyrus
machadoi (Acanthocephala, Quadrigyridae), registrados por primera vez en el Sistema Paraná
Medio. Se determinó la prevalencia parasitaria para cada caso (P= 20,31 %, H. malabaricus; P=
28,6 %, P. maculatus) y se realizó una descripción ampliada del ictioparásito. Este trabajo amplía
la distribución geográfica de Q. machadoi, para ambos hospedadores, así como un aporte al
conocimiento de los ictioparásitos asociados a la fauna íctica regional.
regional icthyoparasite species because of their
high ecological value given by the different roles
they play in the trophic patterns, their
participation in the dynamics of the alluvial
valley and the interactions in which they
participate. Consequently, the aims of this work
were to study the parasitism of H. malabaricus
and P. maculatus by Q. machadoi, in the
wetlands associated with the San Javier River,
Santa Fe, Argentina and to provide an extended
redescription of Q. machadoi.
Sixty four H. malabaricus and seventy P.
maculatus specimens were captured in two
lentic aquatic ecosystems associated with the
San Javier River, in middle areas of the Paraná
system alluvial valley, Cayastá (Santa Fe,
Argentina). The fish were caught with trawl nets
of different mesh size (50 to 140 mm). For this
study, helminths found within intestines were
separated and preserved in alcohol 70 %, and
then fixed, colored and mounted following the
usual helminthology techniques (Eiras et al.,
2003). Taxonomical determination was based on
original publications and taxonomic keys (Van
Cleave, 1952; Yamaguti, 1963; Schmidt &
Hugghins, 1973; Fabio, 1983; Thatcher, 2006;
Santos et al., 2008). The measurements are
represented in mm and the drawings are the
originals. Parasite infestation (P) prevalence for
both hosts was considered. Parasite
representative specimens were placed in the
Helminthological and Invertebrates Collection
of the Argentine Museum of Natural Sciences
“Bernardino Rivadavia” (Buenos Aires) and in
the Invertebrates Collection of the Provincial
Museum of Natural Sciences “Florentino
Ameghino” (Santa Fe).
Quadrigyrus machadoi parasite prevalence by
host is shown in Fig. 1. Based on the 69 Q.
machadoi specimens obtained, a detailed
description is presented and shown in Fig. 2.
Since the structures of Q. machadoi are similar
in both hosts, the description has been unified.
Campos, Río de Janeiro, Brazil, which made H.
malabaricus its final host. In turn, larvae of Q.
machadoi were collected in Cichla monoculus
(Agassiz, 1831), Gymnotus spp. and
Hemisorubim platyrhynchos (Valenciennes,
1840) as paratenic hosts (Machado et al., 2000;
Isaac, 2002; Guidelli et al., 2003). Rosim et al.
(2005) registered the presence of their
cystacanths in the mesentery and mature females
in the intestine of H. malabaricus. The main
features that distinguish this acanthocephala
from those referred to above have to do with the
location of the testicles, which in Q. machadoi
are juxtaposed whereas in Q. torquatus are
separated; they also differ in hook size, those of
the first and second row being bigger and much
smaller than those of the third and fourth rows.
On the other hand, Q. machadoi differs from Q.
brasiliensis in having a shorter body length,
bigger lemnisci and the testes placed next to the
cement gland (Fabio, 1983).
In this region, many people value and frequently
consume freshwater fish. Besides, recreational
fishing of freshwater species activates important
economic resources thus creating interesting job
opportunities (Padín, 2003). The icthyc species
considered in this work form part of the native
fauna both can be caught in the Middle Paraná
floodplain and are among those that are highly
valued by the local population. H.malabaricus, a
fish from the Erythrinidae Family
(Characiforms) popularly known as “tararira” or
“dientudo”, presents a wide geographical
distribution being found from Costa Rica as far
south as Argentina (Oyakawa, 1998). Another
well-known species, Pimelodus maculatus La
Cepède, 1803 (Pimelodidae Family,
Siluriforms), “amarillo” or
“bagre amarillo”, can be found all over the
floodplain of the River Plate Basin (Ringuelet et
al., 1967; Reis et al., 2003).
The San Javier River is a secondary water course
of the Middle Paraná constituted by alluvial
deposits that make up islands which later unite to
form the flood plain, where confined
environments abound (Bó, 2005).
Therefore, further research is needed about the
generally known as
189
Neotrop. Helminthol., 7(2), 2013
MATERIAL AND METHODS
RESULTS
190
Quadrigyrus machadoi Fabio, 1983
Quadrigyridae Van Cleave, 1920
Gyracanthocephalidea Van Cleave, 1936
Eoacanthocephala Van Cleave, 1936
Host: Hoplias malabaricus.
Prevalence, parasite number: 20.31 % (13 of 64
fish infected).
Accession number: MACN-Pa 548 (female);
MACN-Pa 549 (male); MFA-ZI 05 (female);
MFA-ZI 06 (male).
Host: Pimelodus maculatus
Prevalence, parasite number: 28.6 % (20 of 70
fish infected).
Accession number: MFA-ZI 07 (female); MFA-
ZI 08 (male).
General description: Small and medium-sized
helminths with an elongated body that exhibits a
considerable increase in diameter in the anterior
region. They possess a globular proboscis with
four rows of five hooks each and an elongated
lemniscus with a nucleus. The sheath of the
proboscis has a single muscular wall. The
lacunar system has irregularly branched chains
and the trunk presents four rows of small hooks
or cuticular spines.
Males: Maximum length (ML) 3.714 (1.436-
5.904; n=41) and maximum width (MW) 0.503
(0.257-0.912; n=41). Relation between body
length/width 7.813 (3.169-14.807; n=40)/1.
Proboscis: length (L) 0.264 (0.126-1.584; n=27)
and MW 0.151 (0.024-0.192; n=26). Hooks
formed by a circular base and a tine. First row:
base L 0.026 (0.006-0.042; n=22), width (W)
0.013 (0.008-0.020; n=21) and tine L 0.059
(0.042-0.098; n=36); second row: base L 0.022
(0.003-0.064; n=23), W 0.016 (0.003-0.016;
n=23) and tine L 0.044 (0.002-0.068; n= 30);
third row: base L 0.016 (0.002-0.052; n=23), W
0.014 (0.003-0.060; n=23) and tine L 0.037
(0.018-0.168; n=28); last row: base L 0.013
(0.003-0.022; n=19), W 0.010 (0.008-0.016;
n=18) and tine L 0.028 (0.016-0.040; n=20).
Lemnisci differing in size: the largest is 0.434 in
length (0.198-0.653; n=27) and the smallest is
0.414 in length (0.237-0.653; n=19). Receptacle
of the proboscis: L 0.469 (0.092-0.752; n=27).
Cuticular spines on the trunk, arranged in four
rows uniformly separated: L 0.020 (0.010-
0.140; n=32). Two juxtaposed testicles, anterior:
L 0.302 (0.108-0.811; n=28) and W 0,142
(0.039-0.288; n=26); posterior: L 0.280 (0.128-
0.811; n=25) and W 0.163 (0.042-0.277; n=19).
Cement gland remote from the testicles in
posterior direction: L 0.614 (0.049-1.416;
n=22). Cement reservoir: L 0.304 (0.070-0.623;
n=23). Seminal vesicle: L 0.466 (0.086-1.536;
n=20). Saefftigen's pouch: L 0.178 (0.108-
0.552; n=19). Visible and terminal copulating
pouch: L 0.211 (0.044-0.480; n=22).
Chemes & Brusa
Quadrigyrus machadoi in native fish from Argentina
Figure 1. Quadrigyrus machadoi parasite prevalence by host.
Figure 2. A.
Neotrop. Helminthol., 7(2), 2013
Figure 2. Quadrigyrus machadoi (Eoacanthocephala, Quadrigyridae). (scale bar in micrometers). A. Male, entire body ventral
view. B. Proboscis. C. Female, entire body ventral view.
Figure 2. B.
Figure 2. C.
191
Chemes & Brusa
Quadrigyrus machadoi in native fish from Argentina
The specimens found in this study correspond to
the description of Q. machadoi reported by
Fabio (1983), with some particular features.
They have a smaller proportion in the
length/width ratio of the body, the proboscis in
females has a smaller diameter and the hooks of
the proboscis are smaller, even though arranged
in 4 rows and respecting the same proportions as
in the original description (the hooks in the
smaller rows are a third smaller than the hooks in
the first two rows). Similar to the hooks of the
proboscis, lemnisci have a smaller size in the Q.
machadoi specimens from the wetland areas
associated with the San Javier River.
This disparity among specimens of the same
species could be attributed to regional
differences (Eiras et al., 2003). Both H.
malabaricus and P. maculatus are widely
distributed species in the neotropical region and
they are generalists due to their trophic habits.
This condition has been associated with parasite
helminths also of wide geographical
distribution, as evidenced by Q. machadoi in the
present work (Aguilar-Aguilar et al., 2005).
Further studies will be needed to broaden the
register of this parasite in several icthyc species
and in other rivers of the basin, thus contributing
to accrue the knowledge base on these
organisms. The importance of this description
should be remarked, being the first reference to
Q. machadoi in H. malabaricus and P.
maculatus of the Middle Paraná region, San
Javier River, Santa Fe, Argentina.
This study was financed by the Research and
Development Project (CAI+D) 2009-2011 N°
47-233 (FHUC-UNL).
DISCUSSION
Females: ML 4.104 (2.232-7.200; n=28) and
MW 0.511 (0.327-1.032; n=28). Relation body
length/width: 8.566 (2.348-17.834; n=28).
Proboscis: L 0.180 (0.118-0.384; n=19) and MW
0.163 (0.110-0.198; n=19). Hooks formed by a
circular base and a tine or hook. First row: base L
0.034 (0.018-0.058; n=16), W 0.015 (0.006-
0.024; n=16) and tine L 0.062 (0.042-0.082;
n=25); second row: base L 0.030 (0.014-0.050;
n=16), W 0.013 (0.010-0.018; n=16) and tine
0.052 (0.026-0.074; n=19); third row: base L
0.019 (0.012-0.028; n=16), W 0.011 (0.008-
0.018; n=16) and tine L 0.042 (0.016-0.168;
n=20); last row: base L 0.017 (0.010-0.024;
n=12), W 0.011 (0.008-0.018; n=12) and tine
0.031 (0.016-0.050; n=14). Cuticular spines on
the trunk, arranged in four rows uniformly
separated: L 0.020 (0.006-0.168; n=25). The
largest lemniscus is 0.398 in length (0.217-
0.485; n=16) and the smallest lemniscus is 0.379
in length (0.267-0.465; n=15). Receptacle of the
proboscis: L 0.417 (0.104-0.623; n=16). Vagina:
L 0.073 (0.010-0.148; n=19). Uterine bell: L
0.166 (0.032-0.504; n=18). Tubular uterus with
a diameter of 0.111 (0.012-0.544; n=19). Oval-
shaped ovary with sharp edges and medium-
anterior arrangement: L 0.148 (0.026-0.396;
n=20) and W 0.083 (0.014-0.217; n=20).
Distance from the vulva to the rear end of the
body: L 0.835 (0.079-1.336; n=8). Elliptic eggs:
L 0.018 (0.016-0.022; n=3) and W 0.046 (0.012-
0.080; n=2).
Infestation place: intestine.
Origin: lentic habitats associated with the San
Javier River, Cayastá, Santa Fe, Argentina).
Previous record in Neotropical countries: Cichla
kelberi Kullander & Ferreira, 2006, Gymnotus
carapo Linnaeus, 1758, Hemisorubim
platyrhynchos Valenciennes, 1840, H.
malabaricus, Pimelodus maculatus,
Potamotrygon motoro Müller & Henle, 1841, P.
falkneri, Castex & Maciel, 1963. They were
reported in Campos, Río de Janeiro; Aguaí, São
Paulo and in the Upper Paraná River floodplain
(Brazil) (Fabio, 1983; Rosim, 2005; Lacerda et
al., 2008; Takemoto et al., 2009).
ACKNOWLEDGMENTS
BIBLIOGRAPHIC REFERENCES
Aguilar-Aguilar, R, Contreras-Medina, R,
Martínez-Aquino, A, Salgado-
Maldonado, G & González-Zamora, A.
192
Neotrop. Helminthol., 7(2), 2013
specific composition and ecological
aspects. Brazilian Journal of Biology, vol.
63, pp. 261-268.
Composição e estructura das
infracomunidade endoparasitárias de
Gymnotus spp. (Pisces, Gymnotidae) do
rio Baía, na planicie de inundação do alto
rio Paraná, mato Grosso do Sul, Brasil.
Dissertação de Mestrado em Ecologia de
Ambientes Aquáticos Continentais,
Universidade Estadual de Maringá,
Maringá. Acanthocephalen der
Fische des Goktscha-Sees. Zentralblatt
für Bakteriologie, Mikrobiologie und
Hygiene, vol. 108, pp. 146-150.
Lists of species: Digenea,
N e m a t o d a , C e s t o d a , a n d
Aca n thocep h ala, p arasit e s in
Potamotrygonidae (Chondrichthyes)
from the upper Paraná River floodplain,
states of Paraná and Mato Grosso do Sul,
Brazil. Check List, vol. 4, pp. 115-122.
Parasitic
helminths of the freshwater neotropical
fish Hoplias malabaricus (Characiformes,
Erythinidae) from South America Basins.
Reviews in Fisheries Science, vol. 19, pp.
150-156. Sobre alguns
acantocéfalos provenientes do Estado de
Mato Grosso. Revista Brasileira de
Biologia, vol. 1, pp. 57-61.
Ecological aspects
of endohelminths parasitizing Cichla
monoculus Spix, 1831 (Perciformes:
Cichlidae) in the Paraná River near Porto
Rico, State of Paraná, Brazil.
Comparative Parasitology, vol. 67, pp.
210-217. Phylum Acantocephala. In
Woo, PTK. (ed.) Fish Diseases and
Disorders: Vol 1 Protozoan and Metazoan
Infections. Wallingford, UK: CAB
International. Family Erythrinidae. In
Reis, RE, Kullander, SO & Ferraris, CJ Jr.
(eds). 2003. Check List of the Freshwater
Issac, A. 2002.
Kostylew, NN. 1928.
Lacerda, AC, Takemoto, RM & Pavanelli, GC.
2008.
Machado da Rocha, CA. 2011.
Machado Filho, DA. 1941.
Machado, PM, Almeida, SC, Pavanelli, GC &
Tekemoto, RM. 2000.
Nickol, B. 1995.
Oyakawa, OT. 1998.
2005.
Amin, O. 2000.
Bó, RF. 2005.
Chemes, SB & Takemoto, RM. 2011.
Diaz-Ungria, C & Rodrigo, AG. 1957.
Eiras, JC, Takemoto, RM & Pavanelli, GC (eds).
2003.
Fabio, SP. 1983.
Guidelli, GM, Isaac, A, Takemoto, RM &
Pavanelli, GC. 2003.
Aplicación del análisis de
parsimonia de endemismos (PAE) en los
sistemas hidrológicos de México: Un
ejemplo con helmintos parásitos de peces
dulceacuícolas. In Llorente Bousquets, J
& Morrone, JJ (eds.) Regionalización
Biogeográfica en Iberoamérica y tópicos
a f i n e s : P r i m e r a s J o r n a d a s
Biogeográficas de la Red Iberoamericana
de Biogeografía y Entomología
Sistemática. Las Prensas de Ciencias,
México: UNAM.
Acanthocephala in the
neotropical region. In Salgado-
Maldonado, G, García-Alderete, A &
Vidal- Martinez, V. (eds.) Metazoan
parasites in the tropics: A systematic and
ecological perspective. México: UNAM.
Situación ambiental en la
ecorregión Delta e islas del Paraná. In
Brown, A, Martínez-Ortiz, U, Acerbi, M
& Corcuera, J. La situación ambiental
Argentina. Fundación Vida Silvestre
Argentina. Bs.As. Diversity
of parasites from Middle Paraná system
freshwater fishes, Argentina. International
Journal of Biodiversity and Conservation,
vol. 3, pp. 249-266. Revisión
d e l a f a m i l i a Q u a d r i g y d a e
(Acanthocephala), con descripción de
Deltania scorzai gen. n. sp. n. Novedades
Científicas, Serie Zoológica, vol. 22,
pp.1-19.
Métodos de estudio y técnicas
laboratoriales en parasitología de peces.
Editorial Acribia S.A., España.
Sobre alguns acanthocephala
parasitos de Hoplias malabaricus.
Arquivos de la Universidad Federal Rural
de Rio de Janeiro, Itaguaí, vol. 6, pp. 173-
180.
Endoparasites
infracommunities of Hemisorubim
platyrhynchos (Valenciennes, 1840)
(Pisces: Pimelodidae) of the Baía River,
upper Paraná River floodplain, Brazil:
193
Chemes & Brusa
Quadrigyrus machadoi in native fish from Argentina
as a major determinant of endoparasite
species richness in fishes of floodplain of
the upper Parana River, Brazil. Journal of
Helminthology, vol. 79, 7 pp. 5-84.
Helminth fauna of fishes from the upper
Paraná river floodplain, Brazil.
Neotropical Helminthology vol. 4, pp. 5-
8.
Diversity
of parasites of fish from the Upper Paraná
River floodplain, Brazil. Brazilian Journal
Biology, vol. 69, pp. 691-705.
Amazon fish parasites. In
Aquatic Biodiversity in Latin America.
Sofia-Moscow. Two new genera and
species of acanthocephalous worms from
Venezuelan fishes. Proceedings of the
United National Museum, Vol. 58, pp.
455-468. Speciation and formation
of genera in Acanthocephala. Systematic
Zoology, vol.1, pp. 72-83.
The Acanthocephala. Part I
e II. In: Yamaguti, S. (ed.) Sistema
Helminthum. Vol. V. New York:
Interscience Publishers.
Takemoto, RM & Lizama, MAP. 2010.
Takemoto, RM, Pavanelli, GC, Lizama, MAP,
Lacerda, ACF, Yamada, FH, Moreira, LH,
Ceschini, TL & Bellay, S. 2009.
Thatcher, VE. 2006.
Van Cleave, HJ. 1920.
Van Cleave, HJ. 1952.
Yamaguti, S. 1963.
Fishes of South and Central America.
EDIPUCRS. Porto Alegre.
Aspectos institucionales de la
gestión de los recursos acuáticos de la
Cuenca del Plata (o Por dónde
comenzar). In Cappato, J, Oldani, N &
Peteán, J (eds). Pesquerías continentales
en América Latina. Hacia la
sustentabilidad del manejo pesquero.
Secretaría de Extensión, Universidad
Nacional del Litoral, Santa Fe.
Check list of the freshwater fishes of South
and Central America. EDIPUCRS, Porto
Alegre, Brasil.
Los peces argentinos
de a gua d ulce. Comi s i ó n d e
Investigaciones Científicas de La Plata,
Buenos Aires, Argentina.
Parasitismo de Hoplias
m a l a b a r i c u s ( B l o c h , 1 7 9 4 )
(Characiformes, Erythrinidae) por
Quadrigyrus machadoi Fábio, 1983
(Eoacanthocephala, Quadrigyridae) de
uma Lagoa en Aguaí, Estado de São
Paulo, Brasil. Revista Brasilera de
Parasitología Veterinaria, vol. 14, pp. 147-
153. In
vertebrate Zoology, A Functional
Evolutionary Approach. Belmont, CA:
Thomson, Brooks/Cole.
Checklist of Acanthocephala
associated with the fishes of Brazil.
Zootaxa, vol. 1938, pp. 1-22.
Acanthocephala of South American
Fishes. Part I, Eoacanthocephala. The
Journal of Parasitology, vol. 59, pp. 829-
835.
Host density
Padín, OH. 2003.
Reis, RE, Kullander, SO & Ferraris, CJ Jr. 2003.
Ringuelet, RA, Arámburu, RH & Alonso de
Aramburu, A. 1967.
Rosim, DF, Ceccarelli, PS & Silva-Souza, AT.
2005.
Ruppert, E, Fox, R & Barnes R. 2004.
Santos, CP, Gibson, DI, Tavares, LER & Luque,
JL. 2008.
Schmidt, GD & Hugghins, EJ. 1973.
Takemoto, RM, Pavanelli, GC, Lizama, MAP,
Luque, JL & Poulin, R. 2005.
Correspondence to author/ Autor para
correspondencia:
Silvina B. Chemes
School of Humanities and Sciences, National
University of Litoral. Ciudad Universitaria s/nº,
Paraje El Pozo, S3000Z, Santa Fe, Argentina.
Telephone: 54-342-4575105, int.128.
E-mail / Correo electrónico:
schemes@fhuc.unl.edu.ar
Received April 19, 2013.
Accepted June 22, 2013.
194
