Paraschistura makranensis, a new loach from the Jegin River drainage in southern Iran with comments on P. ilamensis and P. pasatigris (Teleostei: Nemacheilidae)
Author
Eagderi, Soheil
Author
Mousavi-Sabet, Hamed
Author
Freyhof, Jörg
text
Zootaxa
2019
2019-09-10
4668
2
258
270
journal article
25485
10.11646/zootaxa.4668.2.6
bf522066-d756-4fe2-be4d-d2b6b170562e
1175-5326
3449341
C8C5FA5C-7704-4336-9E73-1BB94E89249C
Paraschistura makranensis
,
new species
(
Fig. 2–8
)
Holotype
.
IMNRF-UT-1093-16, 33 mm SL;
Iran
:
Hormuzgan prov.
:
Jegin River
at
Jegin
,
26°09’43.1” N
57°53’30.0” E
.
Paratypes
.
IMNRF-UT-1093, 2,
27–32 mm
SL; IMNRF-UT-2093, 3,
26–30.4 mm
SL;
FSJF 3684
,
2
,
23–27 mm
SL
;
VMFC PM-P
, 14, 27–
39 mm
SL; same data as holotype
.
Material for molecular genetic analysis.
IMNRF-UT-2093- CO1-3, 3, same data as
holotype
; (Genbank accession numbers:
MN
258033
,
MN
258034
,
MN
258035
).
Diagnosis.
Paraschistura makranensis
is distinguished from all other
Paraschistura
species in
Iran
by a combination of characters, none of them unique. It is distinguished from its congeners in
Iran
except
P. delvarii
,
P. turcmenica
, and some populations of
P. naumanni
by having a plain brown or slightly mottled colour pattern on the flank (vs. flank with bars, at least on the caudal peduncle), and from all species except
P. cristata
by having a complete (vs. incomplete) lateral line.
It is further distinguished from
P. bampurensis
and
P. cristata
by having 7½ branched dorsal-fin rays (vs. usually 8½, rarely 7½ or 9½), and a shorter caudal fin (14–16% SL vs. 17–19% SL); from
P. alta
by presence (vs. absence) of a small and pointed processus dentiformis in the upper jaw, and an emarginate (vs. deeply forked) caudal fin. It is further distinguished from
P. cristata
by having a shallow dorsal adipose keel on the caudal peduncle without procurrent rays (vs. a prominent dorsal adipose crest supported by 22–25 procurrent rays) and presence (vs. absence) of a suborbital flap in males.
The new species is further distinguished from
P. delvarii
by presence (vs. absence) of a shallow dorsal adipose keel on the caudal peduncle, and absence (vs. presence) of flank scales anterior to the dorsal-fin origin. It is further distinguished from
P. ilamensis
,
P. susiani
and
P. nielseni
by absence (vs. presence) of scales on the back and flank anterior to the dorsal-fin origin.
Paraschistura makranensis
is further distinguished from
P. naumanni
by having the pelvic-fin origin located posterior to the dorsal-fin origin (vs. pelvic-fin origin situated below or slightly anterior to the vertical through the dorsal-fin origin), and absence (vs. presence) of scales on the back and flank anterior to the dorsal-fin origin. It is further distinguished from
P. kermanensis
by presence (vs. absence) of a suborbital flap in males and having the pelvic-fin origin situated posterior to the vertical through the dorsal-fin origin (vs. in anterior to or below). It is further distinguished from
P. kessleri
,
P. turcomana
and
P. turcmenica
by presence (vs. absence) of caudal peduncle scales, and presence (vs. absence) of a suborbital flap in males.
FIGURE 1
. Maximum likelihood estimation of the phylogenetic relationships based on the mitochondrial COI barcode region. Nucleotide positions with less than 95% site coverage were eliminated, resulting in 652 analysed positions. Values at nodes correspond to BI posterior probability/ML bootstrap.
Description.
For general appearance, see
Figures 2–6
. Morphometric data are provided in
Table 3
. Small and slender species with relatively short head. Body deepest midway between nape and dorsal fin origin, depth decreasing slowly towards caudal-fin base. Greatest body width at centre of pectoral-fin base. Section of head roundish, flattened on ventral face. Caudal peduncle compressed laterally, 1.2–1.4 (mean 1.3) times longer than deep. Pectoral fin reaching approximately 50–65% of distance from pectoral-fin origin to pelvic-fin origin. Pelvic axillary lobe absent, or if present fully attached to body. Pelvic-fin origin below second or third branched dorsal-fin ray. Pelvic fin not reaching to anus. Anal-fin origin about one eye diameter posterior to anus. Anal-fin origin at vertical through mid-distance between dorsal- and caudal-fin origins. A shallow dorsal adipose keel without procurrent rays on caudal peduncle. Margin of dorsal fin straight or slightly convex. Caudal fin deeply emarginated. Largest known specimen
40 mm
SL.
Dorsal fin with 7½ and anal fin with 5½ branched rays. Caudal fin with 8+8 branched rays. Pectoral fin with 9–10 (usually 9) and pelvic fin with 6–7 branched rays. Scales absent on back and flank anterior to dorsal-fin ori- gin. Only small, isolated, deeply-embedded scales on caudal peduncle. Lateral line complete, reaching to or almost touching caudal-fin base. Anterior nostril opening at tip of a pointed and flap-like tube. Nostrils separated by a narrow space, posterior tip of anterior nostril not overlapping posterior nostril when folded backwards. Male with a suborbital flap.
FIGURE 2.
Paraschistura makranensis
, IMNRF-UT-1093-16, holotype, 32.7 mm SL; Iran: Jegin River.
Mouth small, strongly arched (
Fig. 7
). Lips moderately thick, with many deep furrows. A median interruption in lower lip. Upper lip with median incision. Processus dentiformis small and pointed. A shallow median notch in lower jaw. Barbels short, inner rostral barbel not reaching base of maxillary barbell, outer one reaching to or slightly beyond base of maxillary barbel, reaching vertical through anterior nostril. Maxillary barbel reaching vertical through distal part of eye.
Coloration.
Body plain grey or pale brown, slightly mottled with yellow belly in life (
Fig. 6
), yellowish in preserved individuals (
Figs. 4–5
). Head dark-grey on top and side, cheek silvery cream. A prominent, irregularlyshaped, dark brown blotch at posterior extremity of caudal peduncle, notched or interrupted by 1–2 white streaks shortly above mid-height in some individuals. Dorsal and caudal fins hyaline, with elongated spots on rays. A prominent, usually large black, spot at base of unbranched dorsal-fin rays. Dorsal and caudal fins hyaline with faded black spots and stripes on rays, absent in some individuals. Pectoral, pelvic and anal fins hyaline.
Etymology.
The species name
makranensis
refers to Makran, an ancient Persian word referencing the area along the coast of the
Oman
Sea. An adjective.
Distribution.
Paraschistura makranensis
is known from the upper Jegin River drainage (
Fig. 9
).
Remarks.
The descriptions of
P. pasatigris
(
Freyhof
et al
. 2015
)
and
P. ilamensis
(
Vatandoust & Eagderi 2015
)
were published almost simultaneously and both species occur in the same watershed. We were able to compare materials from both
type
localities as well as molecular characters (COI) of both species and found no differences between them. We therefore conclude that these two names represent a single species. To clarify the synonymy, the Principle of Priority (ICZN Article 23) is applied (
ICZN 1999
).
Paraschistura ilamensis
became available online on
25 June 2015
with no mention of its online archiving in ZooBank, i.e., the online publication does not meet the criteria for archiving on ZooBank (despite it being archived on
25 June
2015
in Zenodo; https://zenodo.org/ record/845474#.XJ4EzdgyXIU). The description itself was printed and distributed on
30th June 2015
, thus
Para- schistura
ilamensis
is available only from this printed description (
ICZN 1999
). The description of
P. pasatigris
was printed and distributed on
2nd July 2015
(F. Pfeil, pers. com), therefore
P. ilamensis
has two days’ priority over
P. pasatigris
and
P. pasatigris
has to be treated as a junior synonym of
P. ilamensis
.