Tapeworms (Cestoda: Proteocephalidae) of Australian reptiles: hidden diversity of strictly host-specific parasites
Author
Chambrier, Alain De
Author
Beveridge, Ian
Author
Scholz, Tomáš
text
Zootaxa
2018
2018-08-23
4461
4
477
498
journal article
28967
10.11646/zootaxa.4461.4.2
4088067b-9ee8-4fea-b597-059a9de5b6e2
1175-5326
1460246
838E32FD-05BE-47D4-9CF1-E96E7F1C08FF
Australophiotaenia longmani
(
Johnston, 1916
)
n. comb.
(
Figs. 5–10
)
Syns
Crepidobothrium longmani
(
Johnston, 1916
) Meggitt, 1927
;
Proteocephalus longmani
(
Johnston, 1916
) Hughes, Barker & Dawson, 1941
;
Ophiotaenia longmani
(
Johnston, 1911
) Wardle & McLeod, 1952
Type
and only host.
Ramsay’s python,
Aspidites ramsayi
(Macleay, 1882)
(
Ophidia
:
Pythonidae
).
Site of infection.
Intestine.
Type
locality.
Yeulba
(now usually spelled as
Yuleba
),
Queensland
,
Australia
(
26°37′0″S
149°23′0″E
).
Distribution.
Queensland
,
Australia
.
References.
Johnston (1916)
, de Chambrier & de
Chambrier (2010)
;
Scholz
et al.
(2013)
.
Material studied.
6 syntypes
(AHC 20085, 20523, 20733, 28408, QM G16/468, QM 463—16 whole-mounts and 3 cross sections); 4 whole mounts and 9 cross sections of
2 specimens
from
Aspidites ramsayi
in Yuleba
,
Queensland
,
Australia
(MHNG-PLAT-36551; host field number AUS 013).
Redescription.
Based on type-material and recently collected material. Cestodes large, more than
200 mm
in length; maximum width
2.2 mm
. Strobila acraspedote, anapolytic. Immature proglottids wider than long to quadrate (length: width ratio 0.74–1.02), mature, pregravid and gravid proglottids longer than wide (length: width ratio 1.49–3.58).
Internal longitudinal musculature composed by small bundles of muscle fibres. Ventral osmoregulatory canals situated between vitelline follicles and testes. Dorsal osmoregulatory canals almost invisible in mature and gravid proglottids.
Scolex 405–505 (x = 455, n = 6) long and 710–990 (x = 870 n = 6) wide, slightly wider than neck, 530–780 wide. Suckers uniloculate, spherical, slightly embedded, 270–395 (x = 345, n = 24) in diameter, representing 42– 45% of scolex width. Apical organ absent, but diffuse concentration of chromophilic cells present in scolex apex.
Testes medullary, in one layer, forming two lateral bands (poral band separated by terminal genitalia into preporal and postporal groups). Testes 209–275 (x = 242, n = 5) in number, with 108–133 (x = 124, n = 5) aporal testes, 57–76 (x = 67, n = 5) preporal testes and 35–66 (x = 51, n = 5) postporal testes. Testes oval to elongate, 40– 65 long to 35–50 wide, present also in gravid proglottids.
Cirrus-sac oval to pyriform, thick-walled, 340–420 long and 260–290 wide; length: width ratio 0.65–0.80; length of cirrus-sac represents 30–39% (x = 34%, n = 7) of proglottid width. Cirrus robust, its length representing up to 70% of cirrus-sac length. Sperm duct strongly coiled. Vas deferens strongly coiled, situated between proximal part of cirrus-sac and midline of proglottids, but never crossing it. Genital atrium shallow; genital pores alternating irregularly, equatorial or slightly postequatorial, at 49–55% of proglottid length from anterior margin.
Ovary medullary, bilobed, 515–720 wide; width of ovary represents 58–67% (x = 53%, n = 7) of proglottid width; relative size of ovary (see de
Chambrier
et al.
2012
) 2.3%. Mehlis’gland
75–95 in
diameter, representing 8.3–9.3% of proglottid width. Vaginal canal slightly coiled in proximal part, enlarged to form small seminal receptacle dorsal to ovarian isthmus. Terminal (distal) part of vaginal canal (
pars copulatrix vaginae
) surrounded by circular vaginal sphincter and chromophilic cells (
Fig. 7
). Vagina anterior (67%) or posterior (33%, n = 12) to cirrus-sac.
Vitelline follicles paramuscular (i.e. some follicles penetrating to the medulla between fibres of inner longitudinal musculature; see de Chambrier 1990 for definition) arranged in 2 lateral fields near margins of proglottids on the dorsal side (
Fig. 8
), occupying porally 88–97% of proglottid length and aporally 89–94% of proglottid length, interrupted at level of cirrus-sac and vagina (
Figs. 6, 7
).
Primordium of uterine stem medullary, present in immature proglottids. Development of uterus of
type
1 according to de
Chambrier
et al.
(2004
, 2015). In pregravid proglottids, uterus occupying up to 17% of proglottids width, with 32–43 thin-walled lateral diverticula on each side. In gravid proglottids, diverticula occupying up to 75% of proglottid width. Uterine duct entering uterus almost at level of ovarian isthmus.
Eggs in clusters of 3–
6 eggs
(
3 eggs
= 4% of clusters; 4–26%, 5–64%, 6–6%, respectively; n = 78). Outer envelope hyaline, up to
270 in
diameter; embryophore three-layered, 32–36, 29–33, 19–
20 in
diameter, respectively; oncosphere
12–13 in
diameter, with six embryonic hooks 6–8 long.
Remarks.
Johnston (1916)
described this species from somewhat decomposed individuals taken by H. A. Longman from a preserved specimen of
Aspidites ramsayi
, a python captured at Yeulba (another spelling Yeluba) in western
Queensland
(
Johnston, 1916
). Numerous conspecific tapeworms were obtained by one of the present authors (A. C.) in 2001 from the
type
host captured at the
type
locality, but the examined python was frozen before examination. Nevertheless, the new material made it possible to redescribe the species, which seems to be a specific parasite of Ramsay’s python endemic to
Australia
(occurring from
Western
Australia
through southern
Northern
Territory
and northern
South
Australia
to southern
Queensland
and northwestern
New South
Wales
) (
Cogger, 2014
).
Syntypes
of
A. longmani
are smaller than newly collected specimens (total length of
94 mm
versus more than
200 mm
in length; maximum width only
1 mm
in
syntypes
compared to
2.2 mm
in the new material—Johnston, 1916 and present study). This species differs from other species of
Australophiotaenia
described from reptiles in
Australia
by the presence of 3 to
6 eggs
in cluster, and a more powerful longitudinal internal musculature. It differs from
A. mjobergi
by a different PC ratio (30–39% versus 25–28%), and by a different OV% ratio (2.3% versus 4.7%). The cirrus-sac of the species is large and contains a strongly coiled internal sperm duct; the vaginal canal is equipped with a large sphincter.
Scholz
et al.
(2013)
provided sequences of two mitochondrial genes,
rrn
L and
cox
1 (
KC786004
and
KC785991
, respectively), of
A. longmani
from
A. ramsayi
in Yuleba
,
Surat
Road,
Queensland
,
Australia
(host field number AUS 13; paragenophore as MHNG-PLAT-36551).