Neotropical Helminthology, Vol. 19, Nº 2, jul - dec 2025
Federico Villarreal
Volume 19, Number 2 (Jul - Dic) 2025
Neotropical Helminthology, Vol. 19, Nº 2, jul - dec 2025
Figure 1.
Liver of
Procyon cancrivorus
(Procyonidae) with an encysted
Dioctophyme renale
(
Dioctophymatidae) third
-
stage larva (arrow).
Figure 2.
Microscopy of the
Dioctophyme renale
third
-
stage larva of a
Didelphis albiventris
.
a
)
Anterior extremity of the larva.
b
) The
vulvar primordium (arrow) near the intestine (
in
) and
oesophagus (
oe
) junction in a female third
-
stage larva
.
Procyon cancrivorus
Didelphis albiventris
Male (n=1)
Female (n=2)
Male (n=2)
Female (n=2)
Body length
8.34
7.17
–
–
–
8.82
8.82
9.75
–
–
–
10.77
10.77
16.6
–
–
–
20.23
20.23
Pharynx length
0.05
0.087
–
–
–
0.052
0.052
0.05
–
–
–
0.06
0.06
0.022
–
–
–
0.17
0.17
Distance from the first row of
papillae to the anterior
extremity
-
0.00125
0.012
–
–
–
0.015
0.015
0.03
–
–
–
0.027
0.027
Distance from the second row
of papillae to the anterior
extremity
-
0.0275
0.01
–
–
–
0.03
0.03
0.055
–
–
–
0.045
0.045
Distance from the nerve ring to
the anterior extremity
-
0.1
–
–
–
0.087
0.087
0.07
–
–
–
0.10
0.10
0.122
–
–
–
0.102
0.102
Esophagus length
2.50
2.41
–
–
–
3.22
3.22
2.87
–
–
–
3
3
5.01
–
–
–
6.085
6.085
Esophagus% of the total length
29.97
33.61
27.84
–
–
–
29.49
29.49
30.18
–
–
–
30.1
30.1
Width at the esophageal
-
intestinal junction
0.29
0.20
–
–
–
0.202
0.202
0.14
–
–
–
0.19
0.19
0.007
–
–
–
0.122
0.122
Distance of vulvar primordium
to anterior extremity
-
4.087
–
–
–
3.89
3.89
-
6.18
–
–
–
7.39
7.39
Rectum length
0.27
0.19
–
–
–
0.17
0.17
0.10
–
–
–
0.17
0.17
0.245
–
–
–
0.31
0.31
Neotropical Helminthology, Vol. 19, Nº 2, jul - dec 2025
Procyon cancrivorus
the anterior extremity
to anterior extremity
Host species
Site of infection
Locality
Reference
Amphibians
Rana pipiens*
Stomach wall, peritoneal cavity, abdominal muscles
(1st day); skeleticals
(1st day); skeleticals
muscles (5th day);
(1st day); skeleticals
muscles (5th day);
(1st day); skeleticals
(1st day); skeleticals
muscles (5th day);
(1st day); skeleticals
encapsulated in the pectoral muscles, duodenal
wall, legs muscles and mesentery (after 25 days of
infection)
Experimental infection
Mace & Anderson
(1975)
Andrias japonicus*
Stomach wall
Japan
Hasegawa
Hasegawa
et al.
et al.
Hasegawa
et al.
Hasegawa
(2002)
Chaunus
ictericus*
ictericus*
Colied within vesicles underneath the gastric serosa,
partly in the muscular layer
Três Barras (Brazil)
Pedrassani
Pedrassani
et al.
et al.
Pedrassani
et al.
Pedrassani
(2009)
Fish
Ictalurus nebulosus*
Encapsulated in the wall of the stomach or on the
mesentery and one was in abdominal muscles.
Lake Sasajewun (Canada)
Mace & Anderson
(1975)
Lepomis gibbosus*
Encapsulated in the hypaxial musculature, epaxial
musculature, stomach wall, liver, swim bladder wall
and mesentery.
and mesentery.
One free larvae in the hypaxial
One free larvae in the hypaxial
and mesentery.
One free larvae in the hypaxial
and mesentery.
musculature.
Algonquin Provincial Park,
Ontario (Canada)
Measure & Anderson
(1985)
Hoplosternum
littorale*
Encysted in the stomach serous membrane and in
the celoma cavity.
Pelotas (Brazil)
Mascarenhas
Mascarenhas
et al.
et al.
Mascarenhas
et al.
Mascarenhas
(2019)
Turtles
Trachemys dorbigni*
Encysted in coelomic cavity; muscles; stomach
(serous); mesentery; surface of various organs: heart,
lung, liver, pancreas, spleen and intestines
Pelotas and Capão do Leão
(Brazil)
Mascarenhas & Müller
(2015)
Phrynops hilarii*
Celomatic
cavity (surface of esophagus, stomach,
cavity (surface of esophagus, stomach,
lung, liver, and muscles) and serous of stomach
Rio Grande do Sul
Southern (Brazil)
Mascarenhas
Mascarenhas
et al.
et al.
Mascarenhas
et al.
Mascarenhas
(2022)
Acanthochelys spixii*
Cysts in the stomach wall and large intestine
Rio Grande do Sul
Southern (Brazil)
Mascarenhas et al.
(2022)
Hydromedusa
tectifera*
Celomatic cavity (surface of stomach, and muscles)
and serous of stomach
Rio Grande do Sul
Southern (Brazil)
Mascarenhas
Mascarenhas
et al.
et al.
Mascarenhas
et al.
Mascarenhas
(2022)
Snakes
Philodryas
patagoniensis*
Encysted in the coelomic
Encysted in the coelomic
cavity
cavity
Encysted in the coelomic
cavity
Encysted in the coelomic
Capão do Leão (Brazil)
Mascarenhas
Mascarenhas
et al
et al
Mascarenhas
et al
Mascarenhas
et al
.
et al
.
et al
(2018)
Birds
Phimosus infuscatus*
Oesophagus
Pelotas and Capão do Leão
(Brazil)
Scheer
et al.
et al.
(2019)
Mammals
Mustela vison
Mustela vison
Mustela vison
**
**
Mustela vison
**
Mustela vison
Mustela vison
**
Mustela vison
Coiled in the stomach wall and peritoneal cavity
Experimental infection
Mace & Anderson
(1975)
Neotropical Helminthology, Vol. 19, Nº 2, jul - dec 2025
Rana pipiens*
encapsulated in the pectoral muscles, duodenal
wall, legs muscles and mesentery (after 25 days of
Andrias japonicus*
ictericus*
partly in the muscular layer
Ictalurus nebulosus*
Encapsulated in the wall of the stomach or on the
mesentery and one was in abdominal muscles.
Lepomis gibbosus*
Encapsulated in the hypaxial musculature, epaxial
One free larvae in the hypaxial
littorale*
Encysted in the stomach serous membrane and in
the celoma cavity.
Trachemys dorbigni*
Encysted in coelomic cavity; muscles; stomach
lung, liver, pancreas, spleen and intestines
Phrynops hilarii*
cavity (surface of esophagus, stomach,
lung, liver, and muscles) and serous of stomach
Acanthochelys spixii*
Cysts in the stomach wall and large intestine
tectifera*
Celomatic cavity (surface of stomach, and muscles)
and serous of stomach
patagoniensis*
Phimosus infuscatus*
Coiled in the stomach wall and peritoneal cavity
Neotropical Helminthology, Vol. 19, Nº 2, jul - dec 2025