Phylogenetic relationships and taxonomic revision of Paranoplocephala Lühe, 1910 sensu lato (Cestoda, Cyclophyllidea, Anoplocephalidae)
Author
Haukisalmi, Voitto
Author
Hardman, Lotta M.
Author
Hoberg, Eric P.
Author
Henttonen, Heikki
text
Zootaxa
2014
3873
4
371
415
journal article
42366
10.11646/zootaxa.3873.4.3
3762132e-7358-44b3-a430-0708f1fe15f5
1175-5326
229232
7FCB1765-9A81-4BA7-9633-F896B2B808BA
Lemminia
n. g.
(
Fig. 17
)
Etymology.
The name of the new genus refers to the tribe
Lemmini
, to which all known hosts of
Lemminia
spp. belong. “
Lemminia
” is feminine.
Diagnosis.
Strobila short or of moderate length, usually narrow. Scolex globular, merging rather abruptly with neck. Suckers slightly protruding, directed laterally or antero-laterally. Minimum neck width on average 42–56% of scolex width. Proglottids slightly craspedote (velum short), long relative to their width (length/width ratio ca. 50% in mature proglottids). Genital pores unilateral or infrequently (and irregularly) alternating. Genital ducts pass dorsal to longitudinal osmoregulatory canals. Testes forming compact, often oblique group antiporal and anterior to ovary; individual, scattered testes reaching poral side of proglottid, but not being in contact with poral longitudinal osmoregulatory canal. From few to several antiporal testes extending across antiporal ventral longitudinal canal.
Testes mostly not overlapping ovary. Cirrus-sac long and relatively thin, usually slightly curved anteriad, extending across poral longitudinal canals. Vagina tubiform, of uniform width, covered by thin cell layer; overlapping or extending across poral ventral longitudinal canal, slightly shorter than cirrus-sac. Seminal receptacle relatively small, spherical or subspherical. Ovary median or slightly poral. Vitellarium poral with respect to ovary. Early uterus anterior, sparsely reticulated, ventral to other organs, extending laterally beyond longitudinal canals. In lemmings of the genera
Lemmus
,
Myopus
and
Synaptomys
(tribe
Lemmini
) in northern Eurasia and North
America
.
FIGURE 17
.
Lemminia fellmani
from
Lemmus lemmus
. A. Scolex and neck from Finland. B. Mature proglottid from Norway. Redrawn from Haukisalmi & Henttonen (2001).
Type
species:
L. fellmani
(Haukisalmi & Henttonen, 2001)
n. comb.
Paranoplocephala fellmani
Haukisalmi & Henttonen, 2001
Other species:
L. gubanovi
(
Gulyaev & Krivopalov, 2003
)
n. comb.
Paranoplocephala gubanovi
Gulyaev & Krivopalov, 2003
Holotype
of
L. fellmani
:
MZH
20507.
Remarks
. Among genera in the group 3.1. (cestodes with a narrow neck and long vagina relative to the cirrussac),
Lemminia
most closely resembles
Douthittia
.
Lemminia
and
Douthittia
differ from each other primarily in the distribution, number and size of testes. In
Lemminia
testes are rather numerous, small (relative to the proglottid size) and positioned primarily antero-antiporal to ovary, not overlapping the latter. In
Lemminia
, individual testes may occur on the poral side, but they do not reach the poral ventral longitudinal canal. The larger, fewer testes of
Douthittia
are primarily anterior to ovary, usually reaching the poral ventral longitudinal canal and significantly overlapping the ovary (being usually in contact with the vitellarium). Also, the testes of
Lemminia
extend across the antiporal ventral longitudinal canal more markedly than those of
Douthittia
.
Other differences between
Lemminia
and
Douthittia
include the size of the seminal receptacle (smaller in
Lemminia
), the shape of the cirrus sac (slender and anteriorly curved in
Lemminia
, wide and straight in
Douthittia
), and, on average, more elongated proglottids in
Lemminia
.
Lemminia
differs from
Eurotaenia
and
Rauschoides
by its less extensive distribution of testes in the poral part of the proglottid, and from
Rauschoides
and
Arctocestus
by its smaller number of testes lateral to the antiporal ventral canal. More specifically, most of the testes in
Eurotaenia
lie anterior to the ovary, usually overlapping the poral ventral longitudinal canal, whereas in
Lemminia
they are primarily antiporal and antero-poral to ovary, not reaching the poral canal. Also, the vagina of
Eurotaenia
is very thickly beset with intensely-stained cells (the corresponding layer in
Lemminia
is inconspicuous) and the seminal receptacle of
Lemminia
is significantly smaller than that of
Eurotaenia
and their cirrus sacs are of different shapes (more elongated and curved anteriad in
Lemminia
). In addition, the sparsely reticulated (anterior) early uterus in
Lemminia
distinguishes it from all of the other
Paranoplocephala
-like cestodes, including
Eurotaenia
and
Rauschoides
(densely reticulated in the latter).
In all sequence data sets,
L. fellmani
from
Lemmus lemmus
from
Finland
formed a strongly supported clade with
Lemminia
sp. from
Lemmus trimucronatus
from Alaska. In addition, an unidentified species of
Lemminia
from
Synaptomys borealis
from Alaska was strongly associated with
Lemminia
spp. from
Lemmus
spp. in
cox1
data (the specimen from
Synaptomys
could not be amplified for
nad1
). It is assumed that the two unidentified
Lemminia
spp. represent undescribed species; the available material, however, is not suitable for complete description and characterization. The
cox1
data (but neither
nad1
nor concatenated data) showed a slightly supported association (93%) with high genetic divergence between
Lemminia
and
Rauschoides
.