Placobdella akahkway n. sp. (Clitellata: Hirudinea: Glossiphoniidae), a new leech species from central Canada
Author
Fan, Sophia L.
0000-0002-4415-4664
Department of Natural History, Royal Ontario Museum, 100 Queen’s Park, Toronto, ON M 5 S 2 C 6, Canada & Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON M 5 S 2 B 4, Canada & sophia. fan @ alum. utoronto. ca; https: // orcid. org / 0000 - 0002 - 4415 - 4664
sophia.fan@alum.utoronto.ca
Author
Carle, Danielle De
0000-0002-6467-5221
Department of Natural History, Royal Ontario Museum, 100 Queen’s Park, Toronto, ON M 5 S 2 C 6, Canada & Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON M 5 S 2 B 4, Canada & danielle. decarle @ mail. utoronto. ca; https: // orcid. org / 0000 - 0002 - 6467 - 5221
danielle.decarle@mail.utoronto.ca
Author
Kvist, Sebastian
Department of Natural History, Royal Ontario Museum, 100 Queen’s Park, Toronto, ON M 5 S 2 C 6, Canada & Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON M 5 S 2 B 4, Canada
text
Zootaxa
2022
2022-06-29
5159
2
265
280
journal article
84337
10.11646/zootaxa.5159.2.5
8e59f221-0924-4449-90af-8aa61140dc09
1175-5326
6777158
3C59CFCF-041B-4C75-8CBF-EA6711E53B7F
Placobdella akahkway
n. sp.
Figures 2–5
Placobdella
sp. 1
;
de Carle
et al.
, 2017
Diagnosis.
This species can be distinguished from all of its congeners on the basis of its possession of both compact and diffuse salivary tissues. Moreover, the large size of this species, the dorsal pigmentation patterning in combination with the papillation pattern, and its geographic distribution might all lend themselves well to separating this species from other members of the genus. See
Figure 2
for imagery of the external morphology for
type
specimens.
Holotype
.
ROMIZI11495, whole specimen, undissected, in 95% EtOH; from type locality, collected on
June 23, 2016
, by SK and Charlotte Calmerfalk Kvist;
holotype
COI GenBank accession number
OL743155
.
Type locality.
Adams Lake
,
Cypress Hills Provincial Park
,
Saskatchewan
,
Canada
(
49°38.551’N
,
109°50.231’W
). From rocks in shallow water on east side of lake
.
Paratypes
.
ROMIZI11494, whole specimen, undissected, all in 95% EtOH; from type locality, collected on
June 23, 2016
, by SK and Charlotte Calmerfalk Kvist. Three remaining
paratypes
dissected: ROMIZI11247 from
Big Island Lake
,
Alberta
. (
53°29.623’N
,
113°11.831’W
), collected on
June 25, 2016
, by SK and
Charlotte Calmerfalk Kvist
; ROMIZI11464, with brood, from unnamed pond,
Blue Heron Provincial Park
,
Saskatchewan
. (
53°44.903’N
,
105°53.075’W
), collected on
June 19, 2016
, by SK and
Charlotte Calmerfalk Kvist
;
ROMIZI11542 from unnamed pond east of
Lake Winnipeg
,
Manitoba
. (
50°43.371’N
,
96°32.349’W
), collected on
June 8, 2016
by SK and Charlotte Calmerfalk Kvist. All specimens with small part of posterior sucker removed for DNA sequencing
.
Other material examined.
In addition to the
type
series, several specimens collected across
Alberta, Saskatchewan and Manitoba
were examined (
Table 1
). As part of a previous study of the bacterial symbionts of these leeches (
i.e.
,
Manglicmot
et al.
, 2020
), the bacteriomes for all of these specimens were removed, such that none of the specimens is fully intact
.
Etymology:
“
akahkway
” is the Plains Cree word for “leech” in honour of the Indigenous language group spoken at this species’ collection sites (including the
type
locality) in eastern
Alberta
and western
Saskatchewan
,
Canada
.
Description.
Description based on
five specimens
(two fully intact and three dissected specimens). Body dorsoventrally flattened, oval to lanceolate with anterior and posterior tapering and widest at midsection. Anterior end markedly narrower than posterior end. Rather variable colouration, ranging from olive brown, reddish/pinkish brown, to darker greyish brown (
Fig. 2
). Mid-dorsal stripe dark brown and irregularly interrupted; continues past mid-body and ends well before posterior end. Venter beige and without pigmentation or patterning. Average body length
5.27 cm
(
holotype
5.30 cm
), with minimum length 1.0 cm (exception being juvenile specimens at
0.4–0.5 cm
) and maximum length
5.5 cm
. Average body width at male gonopore
2.10 cm
(
holotype
width
3.10 cm
). Complete somites triannulate with partially subdivided annuli throughout (
Fig. 3
). Somites I and II uniannulate; III and IV biannulate: V–XXIII triannulate; XXIV–XXV biannulate; XXVI–XXVII uniannulate. Two pairs of eyespots on III first annulus (a1) in placobdelloid arrangement (
Fig. 4A
). Anus dorsal on XXVII (
Fig. 4B
). Oral sucker
0.5 cm
in diameter with mouth pore on anterior border (
Fig. 4C
). Posterior sucker circular with dorsal papillae (
Fig. 4B
). Five main rows of papillae: 1 medial, 2 paramedial, and 2 lateral. Smaller papillae interspersed outside of main rows, becoming more conspicuous towards posterior end. Throughout body, dorsal papillae punctiform with most prominent papilla on a2. Male gonopore at XI/XII (
Fig. 4D
). Female gonopore at XII a2/a3 (2 annuli between gonopores) (
Fig. 4D
).
FIGURE 2.
Placobdella akahkway
,
n. sp.
dorsal (left) and ventral (right) views. (A) Holotype, ROMIZI11495; (B) Paratype, ROMIZI11464, with young attached to the venter; (C) Paratype, ROMIZI11494; (D) Paratype, ROMIZI11542; (E) Paratype, ROMIZI11247.
FIGURE 3.
Placobdella akahkway
,
n. sp.
Diagram showing segmentation and gross papillation pattern of the holotype specimen. Detailed papillation pattern from somites XVI–XVIII shown as an inset to the right.
Internal body cavity with abundance of dark chromatophores scattered randomly. Relatively large proboscis in membranous sheath, extending linearly and posteriorly to XI a1 (
Fig. 5
). Salivary glands arranged in both a single pair of compact salivary glands and diffuse salivary tissue (
Fig. 5
). Compact salivary glands (posterior pair) in distinct lobes, extending from IX a3-XI a3 and arranged on either side of proboscis. Diffuse salivary glands (anterior pair) interspersed in tissue, concentrated anteriorly and extending from VIII–XI, less concentrated posteriad. Salivary ductules extending from diffuse glands attached to base of proboscis. Esophagus short and folded (
Fig. 5
). Bacteriomes arranged as blind sacs, extending anteriorly from esophagus and folded behind proboscis at X a
2 in
one paratype
(
Fig. 5
). Crop with seven pairs caeca, last pair extending posteriorly to form well-developed post caeca. Intestine with four pairs simple caeca. Male atrial cornuae well-developed with highly coiled ejaculatory ducts (
Fig. 6
). Testisacs in six pairs, intersegmental, from XIII/XIV– XVIII/XIX. Ovaries curled; ovisacs anteriorly bilobed and without common oviduct (
Fig. 6
). Anterior ovisac bifurcation at XII/XIII, anterior lobe extending anteriorly to XII and posteriorly to XIV (
Fig. 6
).
Geographic distribution.
The
species is known from the following lakes and ponds (
Fig. 1
):
Muir Lake
,
Alberta
(
53°37.680’N
,
113°57.393’W
)
;
Half Moon Lake
,
Alberta
(
53°27.351’N
,
113°05.010’W
)
;
Big Island Lake
,
Alberta
(
53°29.623’N
,
113°11.831’W
)
;
Beaver Lake
,
Alberta
(
54°45.400’N
,
111°55.287’W
)
;
Adams Lake
,
Saskatchewan
(
49°38.551’N
,
109°50.231’W
)
;
Cherry Lake
,
Saskatchewan
(
50°23.640’N
,
103°39.571’W
)
;
unnamed pond in
Blue Heron Provincial Park
,
Saskatchewan
(
53°44.903’N
,
105°53.075’W
)
;
Namekus Lake
,
Saskatchewan
(
53°50.320’N
,
106°02.826’W
)
;
Adam Lake
,
Manitoba
(
49°02.607’N
,
100°03.631’W
)
;
unnamed pond
East of Lake Winnipeg
,
Manitoba
(
50°43.371’N
,
96°32.349’W
)
. The distance between the western-most and eastern-most collecting localities (as the crow flies) is roughly
1,230 km
.
FIGURE 4.
Placobdella akahkway
,
n. sp.
external features. (A) eyespots (ey); (B) anus (an) and pre-anal papillae; (C) mouth pore (mp); (D) male (mg) and female (fg) gonopores.
Remarks.
Despite its relatively non-ornate external appearance compared to other select members of this genus [see
e.g.
Placobdella parasitica
(Say, 1824)
], this species displays rather variable sizes and colourations across examined specimens. The three dissected specimens show varying amounts of development of reproductive organs, despite similar overall body sizes.
Placobdella akahkway
closely resembles
Placobdella kwetlumye
Oceguera-Figueroa, Kvist, Watson, Sankar, Overstreet & Siddall,
2010
in overall external appearance but can be separated from this species by the presence of both compact and diffuse salivary tissue (
P. kwetlumye
does not possess diffuse salivary tissues). In addition,
P. akahkway
is considerably larger than
P. kwetlumye
(average body length
5.27 cm
versus
1.77 cm
). Finally, the geographic distributions of the species do not seem to overlap, and the known ranges of each species are separated by a substantial geographic barrier (the North American Cordillera). Distribution might therefore aid in future identifications of specimens.