Comparative Parasitology 68(2) 2001 - Peru State College

AGUIRRE-MACEDO ET AL.—ENDOHELMINTHS FROM NICARAGUAN FISHES 193
Table 2. Measurements of species of Saccocoelioides from Nicaraguan freshwater fishes (n = number of
specimens measured).
Host
Body shape
Body length
Maximum width
Oral sucker
Ventral sucker
Sucker ratio
Position of acctabulum
Prepharynx
Pharynx
Oral sucker/pharynx ratio
Extent of ceca
Tcstis
Hermaphroditic sac
Ovary
Extent of vitellarium
Eggs
Saccocoelioides
sogandaresi
(n = 1)
Poecilia velifera*
Widely oval
995
310
100 X 122
123 X 130
1.14:1
48% of body length
38
90 X 98
1.18:1
Anterior line of testis
102 X 82
150 X 76
—
—
—
Specimens fixed with GAP under pressure.
Ponce de Leon, 1996) from fish of the genus
Rhamdia in the Yucatan Peninsula (see Scholz
et al., 1996).
In South America, cestodes appear to be the
dominant component of the fauna of endohelminths
in freshwater fishes, in terms of the number
of species and genera (Thatcher, 1991; Rego
et al., 1999). These cestodes belong almost exclusively
to the order Proteocephalidea, and they
occur most frequently in siluriform fishes, including
pimelodids (de Chambrier and Vaucher,
1999; Rego, 2000).
The endohelminth fauna of fishes from the
Atlantic coastal drainages of Nicaragua closely
resembles that of southeastern Mexico. Similar
to the larval stages of endohelminths (Aguirre-
Macedo et al., 2001), a majority of species
found occur in congeneric fish hosts from the
Yucatan Peninsula (Moravec et al., 1995; Scholz
et al., 1995, 1996; Salgado-Maldonado et al.,
1997; Scholz and Vargas-Vazquez, 1998; Vidal-
Martinez, Aguirre-Macedo et al., 2001). This
similarity indicates close relationships between
Saccocoelioides sp. 1
(n = 3)
Astyanax fasciatus
Elongate, with tapering ends
1,070-1,210
290-320
90-112 X 100-120
105-115 X 113-125
0.83-1.01:1
33-35%
45-50
70-78 X 63-69
1.35-1.61:1
About midline of testis
274-290 X 140-173
245-280 X 143-160
98-105 X 80-104
Far postacetabular
73-75 X 46-50
Saccocoelioides sp. 2
(« = 15)
Cichlasoma maculicauda
Oval to elongate
470-680
150-335
67-105 X 75-125
56-120 X 50-125
0.63-1.30:1
31-39%
36-72
50-82 X 47-75
1.01-1.46:1
About midline to % of testis
72-175 X 58-145
77-162 X 62-135
37-87 X 35-87
About midline of acetabulum
67-81 X 36-47
the helminth faunas of freshwater fishes in Central
America and southeastern Mexico, in accordance
with the analysis of Vidal-Martinez and
Kennedy (2000) and the general biogeography
of the neotropics (Briggs, 1984). Vidal-Martinez,
Scholz and Aguirre-Macedo (2001) also
found a marked resemblance between gill monogeneans
of cichlids from Nicaragua and those
from Yucatan.
Three species of trematodes, Magnivitellinum
simplex, IP. obesa, and S. sogandaresi, all nematodes,
and the acanthocephalan Neoechinorhynchus
golvani, previously found in North and
South America (Travassos et al., 1969; Thatcher,
1991; Perez-Ponce de Leon et al., 1996; Salgado-Maldonado
et al., 1997; Moravec, 1998), are
reported from Central America for the first time.
With the exception of the trematodes Oligogonotylus
manteri and Crassicutis cichlasomae reported
from Lake Nicaragua by Watson (1976),
all species also represent new geographical records
from Nicaragua. This reflects the shortage
Figures 1—4. 1, 2. Saccocoelioides sp. 1 from Cichlasoma maculicauda. 1. Total view from the ventral
aspect. 2. Tegumental spines at pharyngeal level. 3, 4. Saccocoelioides sp. 2 from Astyanax fasciatus. 3.
Total view ventral from the ventral aspect. 4. Tegumental spines at pharyngeal level. Scale bars in millimeters.
Copyright © 2011, The Helminthological Society of Washington