Protozoa Guide review

SLOPALINIDA

order / SLOPALINIDA

Description

nia Patterson, 1989 BY B. L. J. DELVINQUIER and DAVID J . PATTERSON Slopalines embrace seven genera of endocommensal flagellates occurring mostly in the posterior regions of the intestines of cold-blooded vertebrates . Most opalines have been described . from Anura. The order comprises two families , the Opalinidae and the Proteromonadidae. The F. , Opalinidae consist of five genera and about 4 0 0 The species which have been described in amphibia, reptiles, freshwater and marine fish, and in a few invertebrates. The group has been most recently reviewed by Delvinquier and Patterson (1993) . The Proteromonadidae consist of two genera. There is only a few species of Karotomorpha (from amphibia). There are several species of and Proteromonas occurring mainly in reptiles and more rarely in amphibia and mammals. The 9. opalines have been more extensively studied than proteromonads (Kulda and Nohykova, 1 9 7 8; Metcalf, 1923, 1940; Wessenberg, 1978 ; Delvinquier and Patterson, 1993). The relationships among genera of slopalines is illustrated in Fig. 1. The surface of opalines is covered with rows (kineties) of flagella . As a result, they were first The considered to be ciliates, and Metcalf ( 1 9 2 3 , ov. 1940) referred to them as Protociliates; om however, they lack a number of the pecularities of the ciliates such as dimorphic nuclei and were transferred from the ciliates to the Sarcomastigophora by Corliss and Balamuth (1963). With the recognition of the polyphyly of the Sarcomastigophora, they have been segregated as an independant group. Opalines and proteromonads are placed together because they have a similar and distinctive structure of the flagellum and because in both families the cell surface is underlain by a cortex of evenly spaced microtubules. In the opalines and Karotomorpha, these take the form of ribbons. In Proteromonas, SLOPALINIDA the microtubules are single. On the basis of these Our under ultrastructural similarities proteromonads and Anura . O opalines were combined to form the slopalines the kinet (see Delvinquier and Patterson , 1993) . produced are relea Proteromonas has tripartite hairs attached to the feeding o posterior end of the body which together with destined double-gyred transitional helices in the flagellar between d transition al region indicate an affinity with the (Fig . 2) chrysophyte algae and other stramenopiles Q (Delvinquier and Patterson , 1993). PROTEROMONA S KAROTOMORPHA PROTOZELLERIELLA I ZELLERIELLA PROTOOPALINA CE PEOEA N~ ~"' Numbered items indicate proposed evo luti onary steps . (1) Origins of stramenopiles from biflagellated tubulocristate protists by appearance of tripartit e M + hairs and derivation of a subset with a double-gyred l~' transitional helix . (2) Tripartite hairs reduced to body surface; evenly spaced microtubules underli e cell surface. (3) Complete loss of tripartite hairs , cortical mi crotubules transform into ribbons , and '~~ number of flagella increased to four . (4) Kineties begin to develop ; cells become binucleated , enlarge , and becom e flattened . (5) Kineties become A,B. Grow continuous ; falx distinctive and marginal. (6) Fal x Palintomy becomes axial. (7) Nuclei proliferate and become small cel sma ll er. (8) Return to marginal falx. from the tadpoles. Opalines are thought to have evolved in Anura anisogame from Gondwanaland prior to the break-up of the zygocysts continent in late Jurassic (Delvinquier and (O ,P) , Patterson , 1993) . They now have a world-wide with or w distribution . Proteromo The opalines have a life cycle that is linked to that length , of the host in those species that have been studied. flagella. standing is based on opalines that live in palines grow and divide along and across ies while in their host. Cysts are during the sexual activity of the host and sed into water. Tadpoles are infected by n the cysts. Excysting opalines are to produce gametes. Conjugation occurs issimilar gametes (Wessenberg, 1 9 61 ) . / . .w ' ' FROG D , . .. ! \ \ E •· • ~u \ o · :· \ \ \ \ \ \ @) F· . . l fj;V\H G; . .w~~-~.-~ ~-~ j \, ..~~ ife cycle of Opalina proposed by Wessenberg . th and division of trophonts. C-G . (divisions) leading to the production of ls which form cysts (H). Cysts are shed frog and excys t (I) upon ingestion by The cells which excyst (K) will produce tes (K), which fuse (L) to produce (N). The sexual cycle may be repeated or , alternatively , ce lls may grow and divide ithout cyst formation. nads are small protists , 10-25 1-Jm in mononucleated with apically insert ing Proteromonas is biflagellated with a 756 SLOPALINIDA smooth cortex and material adhering to its KEY TO THE posterio r end. Karotomorpha is quadriflagellated with a pleated or striated cortex . The two genera can be distinguished on the basis of the number of fl agel la. 1. Mononucleated, fla Opalines are usually greater than 100 ~m in ............ Fam length and are binucleated or multinucleated. 1' . Multinucleated , Nucl ei are monomorphic. All opalines have ... .... ... ... flag ell a arranged as kineties . The kineties arise anteriorly at th e falx , which is a morphogenetic 2. Two anterior flage center . 2' . Four anterior fl Opaline genera are distinguished by the number of 3. Binucleated ...... nucl ei and by the orientation of the falx relative to 3' Multinucleated ... the antero -posterior axis of the cell (Fig. 3) . Protozelleriella, Zelleriella , and Protoopalina 4. With long , thin , typi ca lly have two nuclei with a diameter greater the margin and mos th an 10 ~m , but a fe w exceptions are reported . antero-posterior a Opalina and Cepedea are multinucleated with 4' With short , broad nucl ei typical ly less than 10 ~m in diameter. A the direction of t long and thin falx extends along the marg in and the cell. ........ mostly li es transverse to the antero-posterior ax is of ·the ce ll in Proto ze lleriella , Zelleriel/a , 5. Peripheral hyaline and Opalina. This is referre d to as a marginal . . . . . . . . . falx. Alt ernat ively , a short and broad falx lies 5'. Body mostly along the antero-posterior axis of the cell in Protoopalina and Cepedea and is referred to as axial. 6. With long , thin the anteroposter evenly covered w Cep~de a 6' . With short, broa anteroposterio ..... ......... * A few described with four , these species have la which they can be dis Patte rs on, 1993).

Type species

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Raw text

nia
Patterson, 1989
BY
B. L. J. DELVINQUIER and DAVID J . PATTERSON
Slopalines embrace seven genera of
endocommensal flagellates occurring mostly in the
posterior regions of the intestines of cold-blooded
vertebrates . Most opalines have been described
.
from Anura. The order comprises two families ,
the Opalinidae and the Proteromonadidae. The
F. , Opalinidae consist of five genera and about 4 0 0
The species which have been described in amphibia,
reptiles, freshwater and marine fish, and in a few
invertebrates. The group has been most recently
reviewed by Delvinquier and Patterson (1993) .
The Proteromonadidae consist of two genera.
There is only a few species of Karotomorpha
(from amphibia). There are several species of
and
Proteromonas occurring mainly in reptiles and
more rarely in amphibia and mammals. The
9. opalines have been more extensively studied than
proteromonads (Kulda and Nohykova, 1 9 7 8;
Metcalf, 1923, 1940; Wessenberg, 1978 ;
Delvinquier and Patterson, 1993). The
relationships among genera of slopalines is
illustrated in Fig. 1.
The surface of opalines is covered with rows
(kineties) of flagella . As a result, they were first
The
considered to be ciliates, and Metcalf ( 1 9 2 3 ,
ov.
1940) referred to them as Protociliates;
om
however, they lack a number of the pecularities of
the ciliates such as dimorphic nuclei and were
transferred from the ciliates to the
Sarcomastigophora by Corliss and Balamuth
(1963). With the recognition of the polyphyly of
the Sarcomastigophora, they have been segregated
as an independant group. Opalines and
proteromonads are placed together because they
have a similar and distinctive structure of the
flagellum and because in both families the cell
surface is underlain by a cortex of evenly spaced
microtubules. In the opalines and Karotomorpha,
these take the form of ribbons. In Proteromonas,
SLOPALINIDA
the microtubules are single. On the basis of these Our under
ultrastructural similarities proteromonads and Anura . O
opalines were combined to form the slopalines the kinet
(see Delvinquier and Patterson , 1993) . produced
are relea
Proteromonas has tripartite hairs attached to the feeding o
posterior end of the body which together with destined
double-gyred transitional helices in the flagellar between d
transition al region indicate an affinity with the (Fig . 2)
chrysophyte algae and other stramenopiles Q
(Delvinquier and Patterson , 1993).
PROTEROMONA S
KAROTOMORPHA
PROTOZELLERIELLA
I
ZELLERIELLA
PROTOOPALINA
CE PEOEA
N~
~"'
Numbered items indicate proposed evo luti onary steps .
(1) Origins of stramenopiles from biflagellated
tubulocristate protists by appearance of tripartit e
M
+
hairs and derivation of a subset with a double-gyred
l~'
transitional helix . (2) Tripartite hairs reduced to
body surface; evenly spaced microtubules underli e
cell surface. (3) Complete loss of tripartite hairs ,
cortical mi crotubules transform into ribbons , and '~~
number of flagella increased to four . (4) Kineties
begin to develop ; cells become binucleated , enlarge ,
and becom e flattened . (5) Kineties become
A,B. Grow
continuous ; falx distinctive and marginal. (6) Fal x
Palintomy
becomes axial. (7) Nuclei proliferate and become
small cel
sma ll er. (8) Return to marginal falx.
from the
tadpoles.
Opalines are thought to have evolved in Anura anisogame
from Gondwanaland prior to the break-up of the zygocysts
continent in late Jurassic (Delvinquier and (O ,P) ,
Patterson , 1993) . They now have a world-wide with or w
distribution .
Proteromo
The opalines have a life cycle that is linked to that length ,
of the host in those species that have been studied. flagella.
standing is based on opalines that live in
palines grow and divide along and across
ies while in their host. Cysts are
during the sexual activity of the host and
sed into water. Tadpoles are infected by
n the cysts. Excysting opalines are
to produce gametes. Conjugation occurs
issimilar gametes (Wessenberg, 1 9 61 )
.
/ .
.w
' '
FROG
D
, .
..
!
\ \ E •· •
~u \
o · :·
\ \
\
\
\
\
@)
F· .
.
l
fj;V\H G;
. .w~~-~.-~
~-~
j \,
..~~
ife cycle of Opalina proposed by Wessenberg .
th and division of trophonts. C-G .
(divisions) leading to the production of
ls which form cysts (H). Cysts are shed
frog and excys t (I) upon ingestion by
The cells which excyst (K) will produce
tes (K), which fuse (L) to produce
(N). The sexual cycle may be repeated
or , alternatively , ce lls may grow and divide
ithout cyst formation.
nads are small protists , 10-25 1-Jm in
mononucleated with apically insert ing
Proteromonas is biflagellated with a
756 SLOPALINIDA
smooth cortex and material adhering to its KEY TO THE
posterio r end. Karotomorpha is quadriflagellated
with a pleated or striated cortex . The two genera
can be distinguished on the basis of the number of
fl agel la.
1. Mononucleated, fla
Opalines are usually greater than 100 ~m in
............ Fam
length and are binucleated or multinucleated.
1' . Multinucleated ,
Nucl ei are monomorphic. All opalines have
... .... ... ...
flag ell a arranged as kineties . The kineties arise
anteriorly at th e falx , which is a morphogenetic
2. Two anterior flage
center .
2' . Four anterior fl
Opaline genera are distinguished by the number of
3. Binucleated ......
nucl ei and by the orientation of the falx relative to
3' Multinucleated ...
the antero -posterior axis of the cell (Fig. 3) .
Protozelleriella, Zelleriella , and Protoopalina
4. With long , thin ,
typi ca lly have two nuclei with a diameter greater
the margin and mos
th an 10 ~m , but a fe w exceptions are reported .
antero-posterior a
Opalina and Cepedea are multinucleated with
4' With short , broad
nucl ei typical ly less than 10 ~m in diameter. A
the direction of t
long and thin falx extends along the marg in and
the cell. ........
mostly li es transverse to the antero-posterior
ax is of ·the ce ll in Proto ze lleriella , Zelleriel/a ,
5. Peripheral hyaline
and Opalina. This is referre d to as a marginal
. . . . . . . . .
falx. Alt ernat ively , a short and broad falx lies
5'. Body
mostly along the antero-posterior axis of the cell
in Protoopalina and Cepedea and is referred to as
axial.
6. With long , thin
the anteroposter
evenly covered w
Cep~de a
6' . With short, broa
anteroposterio
..... .........
* A few
described with four ,
these species have la
which they can be dis
Patte rs on, 1993).