Three new species and four new species records of earthworms of the genus Moniligaster Perrier, 1872 (Clitellata: Moniligastridae) from Kerala region of the Western Ghats Biodiversity Hotspot, India
Author
Narayanan, S. Prasanth
Advanced Centre of Environmental Studies and Sustainable Development, Mahatma Gandhi University, Priyadarsini Hills, Kottayam - 686560, Kerala, India
Author
Sathrumithra, S.
Advanced Centre of Environmental Studies and Sustainable Development, Mahatma Gandhi University, Priyadarsini Hills, Kottayam - 686560, Kerala, India
Author
Anuja, R.
School of Environmental Sciences, Mahatma Gandhi University, Priyadarsini Hills, Kottayam - 686560, Kerala, India
Author
Christopher, G.
Advanced Centre of Environmental Studies and Sustainable Development, Mahatma Gandhi University, Priyadarsini Hills, Kottayam - 686560, Kerala, India
Author
Thomas, A. P.
Advanced Centre of Environmental Studies and Sustainable Development, Mahatma Gandhi University, Priyadarsini Hills, Kottayam - 686560, Kerala, India
Author
Julka, J. M.
School of Biological and Environmental Sciences, Faculty of Basic Sciences, Shoolini University of Biotechnology and Management Sciences, Solan- 173212, Himachal Pradesh, India
text
Zootaxa
2021
2021-03-25
4949
2
381
397
journal article
7489
10.11646/zootaxa.4949.2.11
e874c6d1-463e-48b3-8d44-2c45ef752a2b
1175-5326
4636238
C792D613-C435-4BC8-8EF7-150427B0D5C4
Moniligaster bahli
Narayanan & Julka
,
sp. nov.
(
Figure 1
)
Type material.
Holotype
:
Clitellate
(ZSI/
WGRC
/IR.INV.8843), grassland, in soil around roots of moss and small grasses growing on rock bed,
Vengolimala in Parambikulam Tiger Reserve
(
10°25'19.1"N
,
76°48'59.7"E
) (
3 km
from Parambikulam),
Palakkad District
,
Kerala
,
India
,
1 August 2016
, 1093 m a.s.l.,
S.P. Narayanan
,
T
.
Augustine
, and
S. Sathrumithra
.
Paratypes
: 7 clitellates (ZSI/
WGRC
/IR.INV.8844), collection data as for holotype
.
Other material.
20 specimens
altogether. 6 clitellates and 1 aclitellate (
ACESSD
/EW/725), moist deciduous forest, between
Parambikulam
tunnel entry and
Vengolimala in Parambikulam Tiger Reserve
(
10°25'10.0"N
,
76°48'16.1"E
),
Palakkad District
,
Kerala
,
India
,
1 August 2016
, 566–
784 m
a.s.l.
,
S.P. Narayanan
,
T
.
Augustine
and
S. Sathrumithra
;
12 clitellates (
ACESSD
/EW/726), evergreen forest,
Karianchola in Parambikulam Tiger Reserve
(
10°27'37.1"N
,
76°49'44.5"E
),
Palakkad District
,
Kerala
,
India
,
4 August
2016
, 733 m a.s.l.,
S.P. Narayanan
,
T
.
Augustine
and
S. Sathrumithra
;
1 clitellate (
ACESSD
/EW/727), evergreen forest,
Karimalagopuram in Parambikulam Tiger Reserve
(
10°21'48"N
,
76°45'9.3"E
),
Palakkad District
,
Kerala
,
India
,
2 August 2016
, 1153 m a.s.l.,
S.P. Narayanan
,
T
.
Augustine
and
S. Sathrumithra
.
FIGURE 1.
Moniligaster bahli
Narayanan & Julka
,
sp. nov.
A.
Ventral view.
B.
Prostate of left hand side, dorsal view.
C.
Prostatic capsule of left hand side, dorsal view.
D.
Spermatheca of right hand side, dorsal view.
E.
Spermathecal atrial glands, ventral view. Abbreviations. C.Atr.D.—Common atrial duct; M.H.L.—Mass of hairpin loops; Pr.C.—Prostatic capsule; Pr.— Prostate; Pr.D.—Prostatic duct; Sp.A.—Spermathecal ampulla; Sp.Atr.G.—Spermathecal atrial gland; Sp.D.—Spermathecal duct; S.M.A.—Secondary male aperture; Sp.P.—Spermathecal pore; T.S.—Testis sac; Vd—Vas deferens.
Diagnosis.
Colour brownish. Length
75–134 mm
, diameter
4.5–7 mm
, segments 135–200. Secondary male apertures paired, transverse slits, lateral to
b
setal lines, at intersegmental furrow 10/11. Spermathecal pores paired, between
bc,
median to setae
c
, at intersegmental furrow 7/8. Genital markings absent. Gizzards
3–4 in
segments 13–18. Vas deferens a mass of hairpin loops, mass larger than testis sac, entering prostate directly, a little below the ental end. Prostates glandular, strap-shaped, slightly sinuous; prostatic capsule tubular with smooth margins and low nodulations entally. Spermathecal atrial glands paired in segment 7, duct of each gland about one fifth the length of common atrial duct.
Description.
External: Colour brownish; body circular in cross section. Dimensions:
Holotype
:
123 mm
by
7 mm
at segment 9, segments 200;
paratypes
:
75–134 mm
by
5–6 mm
at segment 9, segments 135–187; other materials:
92–129 mm
by
4.5–5.5 mm
at segment 9, segments 166–195. Setae lumbricine, closely paired, those on segments 2–7 recognizable only under high magnification; setal formula
aa
=12
ab
= 1
bc
= 8
cd
= 0.23
dd
at segment 8 and
aa
= 14
ab
= 1.35
bc
= 14
cd
= 0.28
dd
at segment 20 (n=1). Clitellum annular, differentiated by pale reddish colour at segments 10–13. Spermathecal pores paired, small transverse slits at intersegmental furrow 7/8, aligned between
bc,
median to setae
c
. Secondary male apertures paired, transverse invaginations at intersegmental furrow 10/11, lateral to seta
b
lines (
Fig. 1A
); small, oval-shaped paired epidermal thickenings in front of secondary male apertures at segments 10 and 11. Female pores paired, minute, at intersegmental furrow 11/12, at
b
setal lines. Nephridiopores minute, recognizable from segment 3, at about seta
d
lines, missing or dislocated dorsally close to mid-dorsal line on some segments. Genital markings absent.
Internal: Septa 5/6–8/9 muscular, septum 9/10 delicate. Gizzards
3–4 in
segments 13–18; intestinal origin in segments 24–26; commissures of extra-oesophageal vessels present on posterior face of septum 8/9. Testis sacs paired, sacs dislocated into segments 17–20, but retaining connections with septum 9/10 by narrow tube-like membranous structures; vas deferens a mass of hairpin loops, extending from segment 9 to segments 12–16, entering prostate directly a little below the ental end without entering musculature, mass larger than testis sac. Prostates paired, extending from segment 11 to segments 15–17, glandular, strap-shaped, slightly widened entally, slender and sinuous ectally (
Fig. 1B
); prostatic capsule tubular, slightly sinuous at the ental and ectal ends, ental end with low nodulations; prostatic duct slightly widened before entering parietes (
Fig. 1C
), about one seventh of the combined length of gland and duct. Spermathecae paired in segment 8, ampulla ovoid, each with a coiled duct penetrating septum 7/8 and posterior atrial gland (
Fig. 1D
) in segment 7 to join at junction of short ducts of atrial glands (
Fig. 1E
); duct of each atrial gland about one fifth the length of common atrial duct, which is slightly bulbous ectally. Ovarian chamber complete; ovisacs in segment 12, extending to segment 20. Nephridia avesiculate; functional at segment 10.
Etymology.
Named after the renowned Indian zoologist, the late Prof. K.N. Bahl (1891–1954), who, in the first half of the last century, made tremendous contributions to the understanding of the excretory system in earthworms.
Ingesta.
Mostly mineralized soil with sparse tiny pieces of mica, quartz, small pieces of cuticles of leaves and bark.
Habitat.
Grassland and evergreen forest.
Distribution.
India
:
Kerala State
: Palakkad District: Parambikulam Tiger Reserve: Vengolimala, Karimalagopuram, Karianchola.
Remarks.
Moniligaster bahli
sp. nov.
belongs to a group of species, characterized by (1) vas deferens opening directly into the prostate, i.e., without penetrating the longitudinal muscle layer, (2) spermathecal atria confined to segment 7, and (3) leaflet like glands absent on the vas deferens. The group consists of five species, three of them described in this paper:
M. gravelyi
Stephenson, 1915
,
M
.
troyi
Jamieson, 1977
,
M
.
blakemorei
Narayanan & Julka
,
sp. nov.
and
M
.
keralensis
Narayanan & Julka
,
sp. nov.
They are compared in
Table 1
. Differences of these species to
M. bahli
sp. nov.
are as follows:
M. bahli
sp. nov.
is distinguished from
M. gravelyi
in the absence of deep marginal incisions on the prostate capsule. It differs from both
M. troyi
and
M. blakemorei
sp. nov.
by the shape of the prostate capsule that is tubular rather than club-shaped. In addition, it can also be distinguished from
M. blakemorei
sp. nov.
by the number of gizzards (3–4 vs 2).
M. bahli
sp. nov.
is differentiated from
M. keralensis
sp. nov.
by the junction of the vas deferens with the prostate gland (at ental end vs ectal end) and intestinal origin (in segments 24–26 vs segments 27–29).