Gastrointestinal nematodes of Paramelomys platyops (Rodentia: Muridae) from Papua Indonesia and Papua New Guinea with the descriptions of a new genus and five new species of Heligmonellidae (Nematoda: Trichostrongylina) and a key to the species of Hughjonestrongylus
Author
Smales, Lesley
text
Zootaxa
2019
2019-10-01
4679
1
107
125
journal article
10.11646/zootaxa.4679.1.7
ae9a0ea1-86c5-4565-99d6-e074236b5bc8
1175-5326
3466308
49CC819D-538B-4623-A2C6-A947D2AAB18C
Flannerystrongylus abulus
sp. nov.
(
Figs 1–15
)
urn:lsid:zoobank.org:act:
4F3B678F-A947-4EF9-A53B-6658FF654BE9
Type
host.
Paramelomys platyops
(Thomas)
Site in host.
Small intestine.
Material examined.
Holotype
male
AM
W.51743,
allotype
female
AM
W.51744,
Kampong Korido
,
Supiori Island
,
Papua
,
Indonesia
(
00° 50´S
135° 36´E
) from
Paramelomys platyops
coll
T
.
Flannery, A
. Szalay
22. ix. 1992
.
Other material examined.
From
Paramelomys platyops
from
Papua New Guinea
,
Madang Province
;
3 males
,
6 females
,
8 male
or female pieces Wanuma, BBM NG103708A;
Etymology.
The species name is derived from abul, a local name used in Sanduan Province, for
P. platyops
.
Description. General:
Relatively large nematodes, coiled anteriorly. Cephalic vesicle prominent with about 8 transverse annulations, buccal capsule vestigial. Mouth opening triangular, with rudimentary lips; cephalic and labial papillae not seen. Oesophagus claviform, nerve ring, deirids not seen; excretory pore in mid region of oesophagus.
Synlophe
: (sections of
10 specimens
) Pointed longitudinal ridges extend from posterior margin of cephalic vesicle to anterior to bursa or vulva; 15 anteriorly, 15 mid body, 14–16, usually 15, posteriorly; axis of orientation sub frontal anteriorly, usually 8 dorsal, 7 ventral ridges, no obvious size gradient either left to right or anterior to posterior.
Male
: (measurements of
3 specimens
) Length 5400–8500 (6740), maximum width 102–148 (133). Cephalic vesicle 51.0–66.0 (59.9) long. Oesophagus not measured; nerve ring, deirids and excretory pore not observed. Bursa dissymmetrical, left lobe larger, pattern of rays 2–3, dorsal lobe shorter than laterals, dorsal ray dissymmetrical, divided at about 1/3 its length, each branch dividing again at tip, terminal divisions rays 9, 10 symmetrical, rays 8 dissymmetrical left ray larger, arising from dorsal trunk at about same level as dorsal ray divides; lateral rays 6 curved dorsally, 4, 5 ventrally, rays 4 largest, rays 2, 3 diverge ventrally, reaching margin of bursa. Genital cone simple, ventral lip longer. Spicules equal, filiform, 440–550 (485) long, spicule to body length ratio 7.2%, tips simple curved. Gubernaculum not symmetrical, dorsal edge shorter and thicker than ventral edge 27.2–29.7 (28.9) long.
Female:
(measurements of
7 specimens
) Length 7200–10,000 (8400), maximum width 119.0–181.5 (151.7). Cephalic vesicle 53–83 (69) long. Oesophagus 400–710 (539); nerve ring and deirids not seen, excretory pore 390 from anterior end (1 measurement). Vulva opens 139.0–165.0 (148.6) from tail tip; large plug of material covers ventral surface from vulva to tail tip in most specimens, some specimens with praepuce; tail may be flexed ventrally. Monodelphic ovejector with short vagina, sphincter, 60, shortest element, vestibule 100, infundibulum, 150, longest element (single measurements). Tail bluntly conical 41.0–80.0 (62.3) long. Eggs thin-shelled ellipsoidal, numerous eggs in utero, 51.0 long by 37.4 wide.
Remarks
. As noted above these specimens were not well fixed and were difficult to handle. Further, the coiling of the anterior end made it difficult to get accurate measurements of the oesophagus and associated features. Nor could the relationship of ridge 1´to the left lateral ridge be determined with any certainty. Sufficient morphological data, however, could be obtained to characterise the new genus.
Following the keys of
Beveridge
et al.
(2014)
Flannerystrongylus
gen. nov.
can be placed in the family
Heligmonellidae
, subfamily
Nippostrongylinae
. The genus differs from the 41 genera described in the family (
Beveridge
et al.
2014
;
Digiani & Durette-Desset 2014
;
Durette-Desset & Digiani 2015
;
Smales 2014
,
2016
,
2017
,
2018
) in the features of the synlophe: usually 15 ridges, 8 dorsal, 7 ventral, with no obvious size gradients and an axis of orientation sub frontal anteriorly. In the key to the 8 genera of nippostrongylins from the Sahul region erected by
Durette-Desset & Digiani (2015)
the genus
Flannerystrongylus
is closest to the genus
Equilophos
Durette-Desset & Digiani, 2015
but differs in having a smaller number of ridges 14–16 compared with 35–36 ridges. Representatives of a further 19 genera from the small intestine have been described from the Sahul and Malaysian regions and can be distinguished by the form of the synlophe as follows: the cosmopolitan
Nippostrongylus
Lane, 1923
has a careen supported by a single hypertrophied ridge.
Heligmonoides,
Baylis, 1928
and
Maxomystrongylus
Hasegawa & Syafruddin, 1997
have
type
B careens,
Orientostrongylus
Durette-Desset, 1970
has a primitive arrangement of the synlophe,
Hasanuddinia
Hasegawa & Syafruddin, 1994
has left ventral and right dorsal ridges larger,
Malaistrongylus
Ow Yang, Durette-Desset & Obayashi, 1983
has left and right dilatations of the synlophe,
Rattustrongylus,
Ow Yang, Durette-Desset & Obayashi, 1983
has 18–19 ridges with the left dorsal ridges smallest,
Sabanema,
Ow Yang, Durette-Desset & Obayashi, 1983
has more than 30 ridges, the left dorsal and right ventral smallest,
Bunomystrongylus
Hasegawa & Mangali, 1996
has both pointed internally supported and rounded unsupported ridges,
Melomystrongylus
Smales & Heinrich, 2010
has a ventral hypertrophied ridge anteriorly,
Mawsonema
Smales &
Heinrich, 2010
has 15 sub frontal ridges anteriorly with a size gradient and a
type
A careen,
Montistrongylus
Smales &
Heinrich, 2010
has 12–15 ridges left ventral largest, oriented at 55° from ventral left to dorsal right in mid body,
Parasabanema
Smales &
Heinrich, 2010
has 45 ridges with a frontal axis of orientation,
Pogonomystrongylus
Smales, 2014
has 7–10 ridges with the left ventral ridges hypertrophied,
Krishnasamyos
Digiani & Durett-Desset, 2014
has 19–21 ridges with ridge 1′ forming a comarete, and the left ridge minute,
Syafruddinema
Digiani & Durette-Desset, 2014
has 14–17 small to minute unevenly sized ridges,
Nuigininema
Smales, 2016
has 17 ridges mid body with an oblique axis of orientation and the ventral and ventral right ridges hypertrophied,
Rodentanema
Smales, 2016
has 6–7 ridges mid body,
Parvinema
Smales, 2017
has 15–17 ridges with an oblique axis of orientation and a careen, the left lateral ridges the largest,
Missimstrongylus
Smales, 2018
has 14 ridges in the mid body with ventral ridge 5′ the largest (Durette- Desset 1970;
Ow Yang
et al.
1983
; Hasegawa & Syafruddin 1994a, 1997;
Hasegawa & Mangali 1996
;
Smales & Heinrich 2010
;
Digiani & Durette-Desset 2014
;
Smales 2014
,
2016
,
2018
).