Simone C. Cohen

Suggested citation: Cohen, S.C. 2013. On diversity of the monogenoidean fauna in a megadiverse country, Brazil. Neotropical

Helminthology, vol. 7, N°1, jan-jun, pp. 1 - 6.

Neotrop. Helminthol., 7(1), 2013

2013 Asociación Peruana de Helmintología e Invertebrados Afines (APHIA)

ISSN: 2218-6425 impreso / ISSN: 1995-1043 on line

EDITORIAL

ON DIVERSITY OF THE MONOGENOIDEAN FAUNA IN A

MEGADIVERSE COUNTRY, BRAZIL

The first author to recognize Monogenoidea as a

distinct taxon was van Beneden (1858), which

divided Trematoda into two groups: the

in 1978, a round table discussed the problems on

nomenclature and decided to adopt the name

Monogenea, since the ending oidea is in

disagreement with the code, which reserves this

ending to superfamily. Boeger & Kritsky (1993)

argued that the name Monogenoidea follows the

priority principle, considering that this name

was the first proposed for the group at class level.

These authors also argued that the ending

“oidea” to superfamily is a recommendation by

inhabiting the gills, skin, nasal fossae, ureters

and few in the intestinal ducts. In amphibians

and aquatic reptiles they may be found in the

mouth, cloaca, or urinary bladder. This group

has been found in a diversity of groups as

mammals (Hippopotamus) and cephalopods

(Boeger & Vianna, 2006).

Infections with parasites are common in cultures

fishes and some groups cause veterinary

problems. Parasites have assumed a central role

been responsible for mortalities or a reduction in

the health of the stocks (Antonelli et al., 2010).

It is not possible to argue that Monogenoidea are

the most important group of parasites, but the

simplicity of the life cycle make them excellent

models to understand the host-parasite

relationship. It had been demonstrated that some

species of Monogenoidea are adequate as

experimental studies models, besides they are

(Poulin, 2002).

In the Monogenoidea, the haptor allows the

attachment on hosts and generally is composed

b y h o o k s , s u c k e r s o r c l a m p s . A s

monogenoideans are mostly soft-bodied and

in various ecological and evolutionary contexts

due its influence in the specificity,

specialization, and the reproductive isolation

(Vignon et al., 2011).

The well-established morphology of the group

provides the language for species description

and diagnosis. However, molecular data have

tended to supplement morphology through a

diversity of taxonomic and evolutionary scales.

Increasingly, molecular markers are being

progress was done in the studies of phylogeny of

most group of helminths, specially the

Neodermata (Littlewood et al., 1999 a,b,

Brooks, 2000, Littlewood & Bray, 2001). The

application of cladistics methods (Brooks, 1989,

Brooks & Mc Lennan, 1993), the intense search

for new adequate characters for phylogeny, as

data on ultrastructure, spermiogenesis, life cycle

(Justine, 1991, 1993, Littlewood & Bray, 2001)

and the wide use of molecular data on

considerable increase of understanding the

phylogenetic relationships within the helminth

groups, including Monogenoidea (Scholz,

Considering that Monogenoidea are the more

specific parasites to their hosts and each fish

species host a different species of

Monogenoidea, is would be possible to predict

that there are 25 000 monogenoidean species in

the world. However, numerous studies made by

Kritsky, Boeger and collaborators indicated that

a single host species can harbor about five

species of Monogenoidea, reaching 25 different

species in Pygocentrus nattereri Kner, 1860

(Boeger & Kritsky, 1988, Kritsky et al. 1988,

leader of freshwater fishes species, with more

than 4000 species, representing approximately

31% of the world freshwater fish species

(Levêque et al., 2008) distributed among 39

different families (Buckup et al., 2007). Despite

the importance of the group as parasites of

fishes, until 1965 only two species had been

described in Brazil: Fredericianella ovicola

Brandes, 1894 and Capsala laevis (Verril, 1874).

In 1965, Mizelle and Price obtained in Steinhart

Aquarium specimens of P. nattereri provenient

from Amazonas and described eight new species

amphibians collected in Para and Rio de Janeiro

states (Kohn et al., 1978). The first species of

Gyrodactylidae in South America was described

gyrodactylid, was described from an amazonian

fish held in an aquarium in England. Oviparous

Kohn & Santos (1989) presented a list of 93

species of Monogenoidea described from Brazil.

In 1998, Kohn & Cohen updated the list,

enlarging the records to South America and

reported 252 species from Brazil, the majority of

growth rate on number of species is related to the

increasement of research on Monogenoidea in

represents the most traditional event for

researchers worldwide that study this group of

parasites. The idea of these meetings was

initiated by R. Ergens and M. Gelnar from the

Czech Republic. The first International

Symposium on Monogenea (ISM) was held on

(ISM 7). This is the first time in American

continent and will enable the participation of

researchers and students of the whole continent.

principles. The Journal of Parasitology,

Boeger, WA, Kritsky, DC & Pie, MR 2003.

Bo e ger, WA & Vi a nn a , RT. 20 0 6.

Proceedings of the Biological Society of

Washington, vol. 101, pp. 87-94.

of Washington, vol. 59, pp. 25-51.

Levêque, C, Oberdorff, T, Paugy, D, Stiassny,

MLJ & Tedesco, PA. 2008. Global

diversity of fish (Pisces) in freshwater.

Hydrobiologia, vol. 595, pp. 545-567.

Littlewood, DTJ. 2008. Platyhelminth

characters. Parasite, vol. 15, pp. 333-341.

Littlewood, DTJ. & Bray, RA. 2001.

Interrelationships of the Platyhelminthes.

ofparasitism. Biological Journal of the

Linnean Society, vol.68, pp. 257-287.

Littlewood, DTJ, Rohde, K & Clough, KA.

1999b. The interrelationships of all major

molecules. Biological Journal of the

Linnean Society, vol. 66, pp. 75-114.

Mizelle, JD & Price, CE. 1965. Studies on

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Szidat, L. 1973. Morphologie und Verhalten von

Paragyrodactylus superbus n.g., n.sp.

Argentinien. Angewandte Parasitologie,

vol. 14, pp. 1-10.

Vignon, M, Pariselle, A & Vanhove, MPM.

2011. Modularity in attachment organs of

African Cichlidogyrus (Platyhelminthes:

Kohn, A & Santos, CP. 1989. Brazilian

Kritsky, DC, Boeger, WA & Jegu, M. 1996.

Kritsky, DC, Boeger, WA & Jegu, M. 1997.

Kritsky, DC, Boeger, WA & Thatcher, VE. 1988.