A new species of algae-scraping cyprinid of the genus Capoeta Valenciennes, 1842 is described from the Kheyroud River, located in the southern part of the Caspian Sea basin in Iran. The species differs from other members of this genus by a combination of the following characters: one pair of barbels; predorsal length equal to postdorsal length; maxillary barbel slightly smaller than eye’s horizontal diameter and reach to posterior margin of orbit; intranasal length slightly shorter than snout length; lateral line with 46–54 scales; 7–9 scales between dorsal-fin origin and lateral line, and 6–7 scales between anal-fin origin and lateral line.

Algae-scraping cyprinid, Caspian Sea, inland freshwater, Iran, taxonomy

Cyprinid fishes of the genus Capoeta Valenciennes, 1842 have a wide distribution throughout western Asia from Anatolia to the Levant, Transcaucasia, the Tigris and Euphrates basins, Turkmenistan, and northern Afghanistan (Bănărescu 1999; Levin et al. 2012; Ghanavi et al. 2016; Jouladeh-Roudbar et al. 2016). This genus has at least 28 species, of which the following 15 species are present in Iran: Capoeta aculeata (Valenciennes, 1844); C. alborzensis Jouladeh-Roudbar, Eagderi, Ghanavi & Doadrio, 2016; C. anamisensis Zareian, Esmaeili & Freyhof, 2016; C. barroisi Lortet, 1894; C. buhsei Kessler, 1877; C. capoeta (Güldenstaedt, 1773); C. coadi Alwan, Zareian, & Esmaeili, 2016; C. damascina (Valenciennes, 1842); C. fusca Nikolskii, 1897; Capoeta gracilis (Keyserling, 1861); C. heratensis (Keyserling, 1861); C. mandica Bianco & Bănărescu, 1982; C. saadii (Heckel, 1847), C. trutta (Heckel, 1843), and C. umbla (Heckel, 1843) (Jouladeh-Roudbar et al. 2015a,b; Alwan et al. 2016; Zareian et al. 2016; Jouladeh-Roudbar et al. 2016). Of these species, eight are endemic to Iran and three have been described recently based on the results of molecular studies (Alwan et al. 2016; Jouladeh-Roudbar et al. 2016; Zareian et al. 2016).

Capoeta species mainly inhabit fast flowing streams and rivers, but some species may also be found in lakes and springs (Turan et al. 2006). The members of this genus possess a fusiform body with small to moderately large scales and an inferior mouth (Coad 2017). Their lower lip bears a keratinized edge and lower lip is restricted to the corner of mouth (Howes 1982; Turan et al. 2006; Coad 2017). The dorsal fin is short with the last unbranched ray thickened, and has serrations posteriorly (serrations sometimes reduced to absent).

The populations of the genus Capoeta from the southern Caspian Sea basin are considered as belonging to two different species: C. gracilis and C. capoeta (Esmaeili et al. 2010; Jouladeh-Roudbar et al. 2015b). Capoeta gracilis was originally described from rivers near Esfahan, central Iran (Esfahan basin) and C. capoeta from Tiflis (Caspian Sea basin), Georgia (the Caspian Sea basin) (Güldenstädt 1773; Temminck and Schlegel 1843; Coad 2017). Several authors have considered C. gracilis as subspecies of C. capoeta, both with allopatric distribution. Capoeta c. gracilis was restricted to rivers between the Sefid and Atrak rivers in the southern part of the Caspian basin in Iran and C. c. capoeta to the Kura-Aras basin in western part of the Caspian basin (Bianco and Banarescu 1982). Furthermore, Bănărescu (1999) restricted the distribution of C. c. gracilis to the Urmia Lake basin and the Sefid River in southern part of the Caspian basin (and also to the lower Kura River in Azerbaijan) while C. capoeta aff. gracilis (an unnamed subspecies related to C. c. gracilis) was considered to inhabit the rest of the Iranian Caspian shore (Jouladeh-Roudbar et al. 2015). Posterior works have considered C. gracilis as a valid species but its distribution has been controversial (Esmaeili et al. 2014).

Currently, molecular studies have shown a high genetic differentiation in the populations of southern Caspian basins considered previously as C. gracilis or C. c. aff. gracilis and this led to the consideration of these populations as an undescribed species (Levin et al. 2012; Ghanavi et al. 2016). The presence of C. capoeta in both the Caspian Sea and Urmia Lake basins was also confirmed based on molecular and morphological data (Ghasemi et al. 2015; Ghanavi et al. 2016).

Previous phylogenetic and phylogeographic studies based on molecular mitochondrial data recognized three main clades within the genus Capoeta, Mesopotamian clade, Aralo-Caspian clade, and Anatolian-Iranian clade (Levin et al. 2012; Ghanavi et al. 2016). The Aralo-Caspian clade is composed by four valid species i.e. C. capoeta, C. heratensis, C. fusca and C. alborzensis in the Iranian freshwater basins (Ghanavi et al. 2016; Jouladeh-Roudbar et al. 2016). A detailed study of the populations of Aralo-Caspian clade in Iran, found some populations of the genus Capoeta, which were not identified as any described species (Ghanavi et al. 2016). Among them were populations distributed in the southern Caspian Sea basin, traditionally identified as C. gracilis (Jouladeh-Roudbar et al. 2015b). Our collection of the genus Capoeta from the southern Caspian Sea basin revealed the presence of two species, i.e. C. capoeta and an undescribed species (considered as Capoeta sp.1 in Ghanavi et al. 2016) that differ molecularly and morphologically from other described Capoeta species including species from the Esfahan basin (Alwan et al. 2016; Ghanavi et al. 2016). According to our intensive samplings from the Esfahan basin, only two species i.e. C. aculeata and C. coadi were found. Therefore, the main goal of this work is to study morphologically the populations of the collected Capoeta specimens from the southern Caspian Sea basin, north of Iran, previously assigned to C. gracilis, and to compare them with the remaining species of this genus from Iran, and based on differences found, they are described as a new species herein.

Approximately 150 specimens of the genus Capoeta were collected by electrofishing at 14 sites covering most of its distribution area in southern Caspian Basin (Figure 1, Table 1). Fin clips stored in 96% ethanol and deposited in the Tissue and DNA Collection of the Ichtyological Museum of Natural Resources Faculty – University of Tehran (IMNRF-UT). The fish were killed with overdoses of MS222, were fixed in 10% formalin, and were later preserved in the Ichthyology collection of IMNRF-UT, Iran. For morphometric purposes and to have a base for molecular studies 23 individuals of C. capoeta and C. fusca from the Urmia Lake and Hari River basins, respectively, were also analysed.

Figure 1. 

Map of the southern Caspian Sea basin and sampling points. Numbers of the sampling sites correspond to the numbers of sampling sites in Table 1, circle: Capoeta razii sp. n., triangle: C. fusca, square: C. capoeta.

Morphological examinations. Thirty morphometric measurements and thirteen meristic character countings were performed using a digital caliper to the nearest 0.1 mm and stereomicroscope, respectively (Tables 4–8). Measurements follow Kottelat and Freyhof (2007). Fin ray counts separate unbranched and branched rays. The last two branched rays articulated on a single pterygiophore in dorsal and anal-fins are noted as “1”.

An allometric method was used to remove size-dependent variation in morphometric characters using following formula (Elliott et al. 1995): M_adj = M(L_s/L₀)^b, where M is the original measurement, M_adj the size adjusted measurement, L₀ the standard length of the fish, L_s the overall mean of the standard length for all fish from all samples in each analysis, and b was estimated for each character from the observed data as the slope of the regression of log M on log L₀ using all fish in any group. The adjusted morphometric characters of the studied populations were analysed using Principal Component Analysis (PCA) and compared by Non-Parametric Multivariate Analysis of Variance (NPMANOVA) based on the P-values obtained from permutation test with 1000 replicates in PAST software (version 2.14). The meristic characters of the studied populations were analysed using Correspondence Analysis (CA), and compared by Non-Parametric Multivariate Analysis Of Variance (NPMANOVA) based on the Bonferoni-corrected P-values obtained from permutation test with 1000 replicates in PAST software (version 2.14).

Molecular data analysis. To analyse the molecular composition we studied the complete mitochondrial cytochrome b gene of all species of Aralo-Caspian group which include an unnamed population from Caspian Sea basin (Levin et al. 2012; Ghanavi et al. 2016). In this study, we considered sequences obtained from previous studies and deposited in GenBank (Table 2) (Levin et al. 2012; Ghanavi et al. 2016; Zareian et al. 2016; Jouladeh-Roudbar et al. 2016). Sequences were aligned using Geneious software (Geneious v. 10.0.2, Biomatters, http://www.geneious.com/), and visually verified to maximize positional homology. Sequences of Luciobarbus capito (Güldenstädt, 1773), L. brachycephalus (Kessler, 1872) and L. subquincunciatus (Günther, 1868) species were chosen as outgroup based on their phylogenetic relationship to genus Capoeta (Levin et al. 2012; Yang et al. 2015; Ghanavi et al. 2016). Uncorrected pairwise genetic distances (p-distances) between species (Table 3) were calculated with Mega 6 (Tamura et al. 2013). A bootstrapping process was implemented with 1000 repetitions. Jmodeltest 2.1.4 (Darriba et al. 2012) selected TrN+I as the best evolutionary model. RAxML (Stamatakis 2006) implemented in GENEIOUS software was used to estimate the maximum-likelihood (ML) tree. Bayesian inference was conducted with MrBAYES v. 3.2.2 (Ronquist et al. 2012). Two simultaneous analyses were run on 2*10⁷ generations, each with four MCMC chains sampling tree every 2000 generations. Convergence was checked on Tracer 1.6 (Rambaut and Drummond 2013). After discarding the first 10% of generations as burn-in, we obtained the 50% majority rule consensus tree and the posterior probabilities. The species delimitation methodology used was Bayesian Poisson tree process (bPTP) model which is based on a distance-based tree (Zhang et al. 2013). bPTP were accessed at Exelixis Labs (http://sco.h-its.org/exelixis/web/software/PTP/index.html). Haplotype genealogies were visualized by HaploView v. 4.2 (Barrett et al. 2005).

Based on the results, from the 1040 bp of complete mitochondrial cytochrome b genes, 793 positions were conserved and 195 were parsimony informative. Genetic distances between species are listed in Table 3. The Bayesian and ML analyses yielded similar topologies with well-supported nodes (Figure 2). The reconstructed topology was also in agreement with previously published higher-level phylogenies that included Capoeta and the three main clades, Aralo-Caspian, Anatolian-Iranian, and Mesopotamian were recovered (Levin et al. 2012; Ghanavi et al. 2016; Jouladeh-Roudbar et al. 2016). Based on molecular phylogeny, the differentiation of populations from Caspian Sea basin from the other described species is shown. The species delimitation methodology also supports these populations to be considered as a different species from the other populations included in the study (Figure 2). The haplotype network does not show any geographical patterns between the different populations of the suggested species in the closely located but independent rivers of the Caspian Sea basin (Figure 3).

Figure 2. 

Capoeta genus; Values at nodes correspond to BI posterior probability/ML bootstrap. Grey bars represent the species delimitations performed with bPTP software.

Figure 3. 

Haplotype networks of available specimens of Caspian Sea basin. Each independent river system is represented by a different colour. Data from Ghanavi et al. 2016.

The result of PCA analysis showed that all specimens explained 45.79% of morphometric variations by the first two PC axes extracted from the variance-covariance matrix (PC1=27.60% and PC2=18.19%). Plotting of first and second PCs displayed a complete segregation of the three populations. In addition, NPMANOVA showed significant differences between all studied populations in terms of the morphometric characters (P<0.001) (Figure 11). The result of CA showed that all specimens explained 63.1% of morphometric variations by the first two CA (PCA1=35.82% and CA2=27.28%). Plotting of first and second CAs displayed a complete segregation of the three populations. In addition, NPMANOVA showed significant differences between all studied populations in terms of the morphometric characters (P<0.0001) (Figure 12).

Capoeta razii , sp. n.

http://zoobank.org/948BD913-A0DF-4371-97F6-B707CE56CFD6

Figures 4, 5, 6, 7

Holotype

IMNRF-UT-1072-9, holotype, 142.6 mm SL. Iran: Mazandaran Prov., Chalus city, Kheyroud River (Figure 8), Caspian Sea basin, 36°36'35"N, 51°33'45"E, S. Eagderi & A. Jouladeh-Roudbar, November 2016.

Paratypes

IMNRF-UT-1072, 14 specimens, 90.7–184.2 mm SL; data same as holotype.

Diagnosis

Capoeta razii sp. n. is distinguished from the other species of Capoeta in Iran by a following combination of characters, none of them unique. One pair of barbels; pre-dorsal length equal to postdorsal length; maxillary barbel slightly smaller than eye’s horizontal diameter and reach to posterior margin of orbit; intranasal length slightly shorter than snout length; lateral line with 46–54 scales, 7–9 scales between dorsal-fin origin and lateral line and 6–7 scales between anal-fin origin and lateral line.

Table 4.

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Morphometric data of Capoeta razii sp. n. (holotype, IMNRF-UT-1072-9; paratypes, IMNRF-1072, 14 specimens) C. capoeta (IMNRF-UT-1067, 15 specimens) and C. fusca (IMNRF-UT-1065, 8 specimens).

Characters	Holotype	C. razii sp. n.			C. capoeta			C. fusca
		Range	Mean	SD	Range	Mean	SD	Range	Mean	SD
Standard length (mm)	142.6	90.7–184.2			66.5–157.3			47.2–124.2
In percent of standard length (SL)
Body depth maximal	23.7	23.1–25.5	23.9	0.7	23.4–26.9	25.2	1.0	24.4–27.1	26.0	0.9
Caudal peduncle depth	12.1	11.1–12.9	11.9	0.5	10.1–12.6	11.7	0.7	11.1–13.5	12.5	0.8
Predorsal length	52.3	50.2–53.1	51.8	0.9	50.8–55.5	52.9	1.2	52.6–55.0	53.8	0.9
Postdorsal length	51.8	49.9–54.2	51.7	1.2	47.6–55.1	51.9	2.1	48.9–52.3	50.6	1.2
Prepelvic length	55.1	55–58.7	56.1	1.1	54.3–61.3	57.1	1.9	55.2–58.6	57.3	1.2
Preanal length	75.9	76.4–79.6	77.6	1.0	74.9–79.7	77.5	1.4	76.7–79.9	78.4	1.3
Caudal peduncle length	18.9	16.1–19.4	17.4	1.1	14.7–20.0	17.2	1.4	14.2–17.9	16.1	1.3
Dorsal fin base length	11.3	12.1–15.4	13.6	0.9	12.7–16.7	14.5	1.4	14.9–18.0	16.5	0.9
Dorsal fin depth	17.7	16.2–21	18.9	1.2	18.5–22.2	20.5	0.9	18.7–26.1	22.3	2.2
Anal fin base length	7.3	6.8–8.3	7.5	0.4	6.0–9.1	7.7	0.8	8.1–10.1	9.1	0.7
Anal fin depth	16.8	15–20.4	17.7	1.4	14.4–18	16.2	1.0	17.1–19.9	18.7	0.8
Pectoral fin length	20.5	17.8–21.3	19.5	1.1	15.4–20.6	18.7	1.9	18.3–24.2	21.2	2.1
Pelvic fin length	16.7	14.1–17.5	16.0	1.0	14.2–17.3	16.0	0.9	15.9–19.9	18.1	1.2
Pectoral – pelvic-fin origin distance	32.3	30.6–36.1	32.8	1.4	31.4–37.0	34.2	1.7	29.5–34.5	32.3	1.8
Pelvic – anal-fin origin distance	20.6	21–24.2	22.2	1.0	18.7–23.0	21.5	1.2	20.1–23.9	22.1	1.4
Body width	16.3	15.1–17	16.0	0.6	16.3–18.4	17.2	0.6	16.6–18.7	17.6	0.7
Caudal peduncle width	3.6	2.8–4.1	3.4	0.5	3.1–4.2	3.7	0.3	5.5–7.0	6.3	0.5
Head length (HL)	22.5	20.5–24	23.0	1.0	19.8–25.9	22.6	1.8	25.0–28.6	26.2	1.7
As percentage of head length (HL)
Snout length	26.2	26.2–31.6	28.7	1.4	24.7–29.8	27.1	1.6	28.2–33.1	30.6	1.9
Eye horizontal diameter	20.1	17.1–26.7	23.3	2.7	17.4–22.7	19.4	1.7	15.4–23.7	19.3	2.9
Postorbital distance	53.5	46.4–54.4	50.7	2.2	47.9–60.8	56.2	3.4	48.1–54.2	52.2	2.0
Head depth at nape	78.3	70.1–82.9	76.4	3.5	67.5–87.5	79.4	5.2	70.3–76.1	72.6	2.0
Head depth at eye	50.2	45.7–53	51.1	2.0	44.8–56.8	52.7	3.2	47.0–53.4	51.2	1.9
Head length at nape	90.1	88.9–97	92.2	2.4	83.8–98.6	92.9	3.9	87.9–96.3	91.5	3.1
Head width	67.6	61.6–73.1	65.9	3.1	62.3–77.3	70.0	5.4	54.9–69.7	60.7	4.7
Inter orbital	42.5	34.3–46	42.8	2.9	41.4–52.2	46.2	3.4	35.7–40.1	37.0	1.4
Inter nasal	26.1	20.2–26	24.7	1.8	24.0–31.3	28.0	2.2	17.1–23.6	20.7	1.8
Mouth width	35.6	28.7–37.9	34.2	2.9	31.4–41.3	36.0	2.9	26.6–38.9	31.3	4.7
Barbel length	13.0	14–21.6	17.2	2.4	9.3–16.2	13.2	1.8	9.9–17.3	13.6	2.9

Table 5.

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Number of scales above lateral line (ALL), below lateral line (BLL), Number Dorsal Soft Rays (DSR)/Hard (DHR), Anal Soft Rays (ASR)/Anal Hard Rays (AHR), pelvic (PLR) fin rays and Number Gill rakers on the lower limb (LOL) in Capoeta razii sp. n. and C. capoeta.

Species	3	4	5	6	7	8	9	10	Mod	Mean	SD
ALL
Capoeta razii sp. n.					3	10	2		8	7.9	0.6
Capoeta capoeta						3	10	2	9	8.9	0.6
BLL
Capoeta razii sp. n.				10	5				6	6.3	0.5
Capoeta capoeta					12	3			7	7.2	0.4
DHR
Capoeta razii sp. n.	1	14							4	3.9	0.3
Capoeta capoeta	7	8							4	3.6	0.5
DSR
Capoeta razii sp. n.					2	13			8	7.9	0.4
Capoeta capoeta					3	12			8	7.8	0.4
AHR
Capoeta razii sp. n.	15								3	3.0	0.0
Capoeta capoeta	15								3	3.0	0.0
ASR
Capoeta razii sp. n.				15					6	6.0	0.0
Capoeta capoeta				15					6	6.0	0.0
PLR
Capoeta razii sp. n.						1	10	4	9	9.2	0.6
C. capoeta							9	6	9	9.3	0.6
LOL
Capoeta razii sp. n.		4	12	1					5	4.9	0.5
Capoeta capoeta		2	11	2					5	5.0	0.5

Table 6.

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Number of pectoral (PFR), caudal fin rays (DFR), total gill rakers (TGR) and circum-pendicular scales (CPS) in Capoeta razii sp. n. and C. capoeta.

Species	15	16	17	18	19	20	21	Mod	Mean	SD
PFR
Capoeta razii sp. n.		2	7	2	1			17	17.4	1.1
Capoeta capoeta				6	5	2	2	18	18.9	1.3
CFR
Capoeta razii sp. n.				1	14			19	18.9	0.3
Capoeta capoeta					10	5		19	19.3	0.5
CPS
Capoeta razii sp. n.			6	9				18	17.6	0.5
Capoeta capoeta				10	3	2		18	18.5	0.7
TGR
Capoeta razii sp. n.	1		2	8	2	1	1	18	18.1	1.4
Capoeta capoeta					2	6	7	21	20.3	0.7

Table 7.

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Number of total lateral-line scales in Capoeta razii sp. n. and C. capoeta.

Species			Total lateral line Scales											Mod	Mean	SD
	46	47	48	49	50	51	52	53	54	55	56	57	58
Capoeta razii sp. n.	2	1	4	2	2	-	2	-	2					48	49.1	2.3
Capoeta capoeta										4	5	4	2	56	56.3	1.0

Table 8.

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Range of meristic features of Iranian Capoeta species.

No.	Species	LL	ALL	BLL	CPS	TGR	Reference
1	Capoeta alborzensis	39–44	6–8	5–8	16–17	19–22	This study
2	Capoeta aculeata	39–43	7–8	5–7	16–20	19–23	This study
3	Capoeta razii sp. n.	46–54	7–9	6–7	17–18	15–21	This study
4	Capoeta anamisensis	56–67	11–12	6–8	–	21–25	Zareian et al. 2016
5	Capoeta barroisi	76–84	14–16	10–13	–	26–29	Turan et al. 2006
6	Capoeta buhsei	80–89	13–15	11–13	29–31	11–13	This study
7	Capoeta capoeta	51–58	9–11	7–8	19–23	17–29	This study
8	Capoeta coadi	68–75	12–15	9–10	25–29	15–18	This study
9	Capoeta damascina	64–82	12–17	8–12	23–30	17–25	Alwan, 2011
10	Capoeta fusca	46–54	8–10	8–9	19–26	16–18	This study
11	Capoeta heratensis	55–61	9–12	7–9	22–25	21–24	This study
12	Capoeta mandica	58–68	12–13	8–10	27–33	23–27	Alwan et al. 2016
13	Capoeta saadi	61–78	9–14	6–10	–	12–17	Alwan, 2011
14	Capoeta trutta	65–82	9–14	9–12	27–31	20–30	This study
15	Capoeta umbla	90–102	18–23	12–14	33–36	18–20	This study

Description

See Figure 4 for general appearance and Tables 4–7 for morphometric and meristic data. Body is moderately deepened and compressed laterally. Greatest body depth occurs at the level of dorsal-fin origin. Dorsal profile of the head is convex. Predorsal length is equal to post-dorsal length. Dorsal profile of the body is convex without any keel in the front of dorsal-fin origin. Snout is rounded with a triangular view in ventral. Mouth is almost straight. Upper and lower lips are adnate to jaws. Lower jaw has a strong keratinized edge. Rostral cap is well developed and usually overlaps with upper lip. One set of maxillary barbels that are short, slightly smaller than eye’s horizontal diameter, reaching to posterior margin of orbit. Intranasal length is slightly shorter than snout length. Pelvic axillary scales are triangular, well developed, and pointed. Dorsal fin has 3–4 unbranched and 7–8 branched rays, its outer margin is straight or slightly concave. Last unbranched dorsal-fin ray is thickened and serrated, distally flexible, and with 15–25 serrae on its posterior margin, with serrations along 50–70% of its posterior margin, denticles are long and narrowly spaced but not strongly developed. Last unbranched dorsal-fin ray slightly shorter than first branched ray, and the tip is soft. Pelvic fins are inserted under posterior of the first branched dorsal-fin base. Caudal fin is deeply forked with pointed and equal size of lobes. Pectoral fin has 16–19 branched rays. Pelvic fin has 1 unbranched and 9–10 branched rays. Anal fin has 2–3 unbranched rays, 6 branched rays and its outer margin is usually convex or straight. There are 15–21 gill rakers on the outer side of the first arch. There are 17–18 circum-peduncular scales. Lateral line is complete, with 46–54 scales. There are 7–9 scales between the dorsal-fin origin and lateral line and 6–7 are located between the anal-fin origin and lateral line.

Figure 4. 

Capoeta razii sp. n., IMNRF-UT-1072-9, holotype, SL: 142.6 mm, Iran: Mazandaran Prov., Chalos city, Kheyroud River, Caspian Sea basin.

Colouration

In life, the upper part of the body is golden brown, olive-green, or silver, and the belly is whitish up to the lateral line. The head is dark-brown or olive-green on top and the cheeks are pale brown to white (Figure 4). Anal, pelvic, and pectoral fins are hyaline or light brown, and dorsal and caudal fins have a narrow black line on rays. In specimen smaller than 50 mm SL, minute black spots are present on flanks.

When preserved, the dorsum is dark brown on back and flanks, and yellowish white on belly (Figure 6). Dorsum of the head is dark brown, and the cheeks beige. Fins are often light brown and pelvic and anal fins may be yellowish to hyaline. Dorsal and caudal fins are darker than lower fins. Peritoneum is black.

Figure 5. 

Ventral view of Head. Capoeta razii sp. n. (right, IMNRF-UT-1072-11, SL: 109 mm) and C. capoeta (left, IMNRF-UT-1067-6, SL: 110 mm).

Figure 6. 

Capoeta razii sp. n., paratypes; A IMNRF-UT-4, SL: 130 mm B IMNRF-UT-12, SL: 115 mm C IMNRF-UT-3, SL: 99 mm.

Distribution and habitat

Capoeta razii is found in many rivers and streams of the southern Caspian Sea basin. It is one of the most abundant species in the Caspian Sea basin along with the members of the genus Alburnoides Jeitteles, 1861. At the Kheyroud River (type locality), the current was medium to fast, river width was between 3–14 m and the maximum depth was around one meter, the stream bed was composed of cobbles and gravel, and the riparian vegetation type was deciduous forests. Following fish species: Poticola iranicus Vasil’eva, Mousavi-Sabet & Vasil’ev 2015, Alburnoides taberstanensis Mousavi-Sabet, Anvarifar & Azizi, 2015, Alburnus chalcoides (Güldenstädt 1772), Barbus cyri De Filippi 1865, Squalius turcicus De Filippi 1865, Luciobarbus capito Güldenstädt 1773, L. mursa Güldenstädt 1773, Cobitis faridpaki Mousavi-Sabet, Vasil’eva, Vatandoust & Vasil’ev 2011, co-exist with C. razii in type locality. Capoeta razii is known from most of rivers and streams between Atrak and Kote komeh (Near Astara city) rivers in southern Caspian Sea basin.

Etymology

The new species is named in honour of Abū Bakr Muhammad ibn Zakariyyā al-Rāzī, a Persian polymath, physician, alchemist, and philosopher, for his important contributions in the history of medicine. He also discovered numerous compounds including Ethanol.

Figure 7. 

Last simple dorsal-fin rays, Capoeta razii sp. n. (Below, IMNRF-UT-1066-9, SL: 116) and C. capoeta (Above, IMNRF-UT-1067-13, SL: 121 mm).

Figure 8. 

Kheyroud River, near Chalos city, Caspian Sea basin, type locality of Capoeta razii sp. n.

Remarks

Capoeta razii sp. n. is distinguished from C. aculeata and C. alborzensis by a smaller scale size and a higher number of total lateral line scales (46–54 vs. 39–44).

Capoeta razii sp. n. is distinguished from C. fusca, by a smaller caudal peduncle width (2.8–4.1 vs. 5.5–7.0 %SL), a smaller head length (20.5–24.0 vs. 25.0–28.6 %SL), and the presence of numerous minute scales on the caudal fin base extending distally onto the fin membranes for more than half the fin ray length (vs. absence of minute scales on the caudal fin base) (Figure 10).

Capoeta razii sp. n. is distinguished from C. anamisensis, C. barroisi, C. buhsei, C. Capoeta, C. coadi, C. damascina, C. heratensis, C. mandica, C. saadi and C. umbla by a larger scale size, a fewer number of total lateral line scales (46–54 vs. 55–102).

Figure 9. 

Uncatalogued live specimen of Capoeta capoeta. Iran: Ajab Shir town, Ghale Chay River, Urmia basin.

Figure 10. 

Live specimen of Capoeta fusca, IMNRF-UT-1065-1, SL: 124 mm, Iran: North Khorasan prov.: Near Farooj town, at segonbadan village, Qanat-e Segonbadan, Hari basin.

Comparative material

– Capoeta aculeata: IMNRF-UT-1058, 9. 53–116 mm SL, Iran: Fars prov.: Tange Boragh village, Kor River, Kor basin, 37°14'46"N, 58°08'01"E, Aug 2014, S. Eagderi & H. Mossavi-Sabet. – Capoeta alborzensis.: IMNRF-1063, 7. 50–153mm SL, Iran: Tehran prov.: Nam River, tributary of Hableh River, near Arjomand village, 35°48'00"N, 52°30'57"E; IMNRF-UT-2063, 23, 46–163mm SL, Iran: Tehran prov.: Nam River, tributary of Hableh River, Kavir basin, near Harandeh village, 35°42'41"N, 52°40'19"E, S. Eagderi & A. Jouladeh-Roudbar, September 2014. – Capoeta buhsei: IMNRF-UT-1075, 12. 103.9–211.8 mm SL, Iran: Markazi prov.: Tafresh town, at Khalife kandy village, Mazlaghan Chay River, Namak basin, 34°45'34"N, 49°56'50"E, Nov 2016, A. Rahmani, M. A. Jahazi, R. Rahbar-zare, A. Jouladeh-Roudbar. – Capoeta capoeta: IMNRF-UT-1067, 15. 66–157 mm SL, Iran: Tabriz prov.: Near Ajab shir city, Ghale Chay River, Urmia Lake basin, 37°29'25"N, 45°59'57"E, Nov 2016, T. Hosseinpour, M. Ahmadian & A. Jouladeh-Roudbar. – Capoeta coadi: IMNRF-UT- 1074, 15. 125.7–194.7 mm SL, Iran: Chaharmahal and Bakhtiari prov.: Near Joneghan town, at Darkesh varkesh village, Behesht Abad River, Tigris basin, 32°05'22"N, 50°39'54"E, Aug 2016, T. Hosseinpour, A. Soleymani & A. Jouladeh-Roudbar. – Capoeta fusca: IMNRF-UT-1065, 8. 46–121 mm SL, Iran: North Khorasan prov.: Near Farooj town, at segonbadan village, Qanat-e Segonbadan, Hari basin, 37°14'46"N, 58°08'01"E, Jun 2016, S. Eagderi & A. Jouladeh-Roudbar. – Capoeta heratensis: IMNRF-UT-1064, 15. 116–161 mm SL, Iran: Khorasan-e Razavi prov.: Near Sarakhs, at Pole-e Khaton, Hari River, Hari basin, 35°56'51"N, 61°08'51"E, Jun 2016, S. Eagderi & A. Jouladeh-Roudbar. – Capoeta trutta: IMNRF-UT- 1073, 15. 54.1–165.2 mm SL, Iran: Kermanshah prov.: Songhor to Satar road, Tape Esmail village, Gavehroud River, Tigris basin, 34°56'01"N, 47°12'49"E, Aug 2016, T. Hosseinpour, A. Soleymani & A. Jouladeh-Roudbar. – Capoeta umbla: IMNRF-UT-1077, 15. 107.3–175.9 mm SL, Iran: Kurdistan prov.: Near Sardasht town, Barisu village, Little Zab River, Tigris, 36°08'48"N, 45°32'17"E, May 2016, S. Eagderi, H. Porbagher, P. Jalili & A. Jouladeh-Roudbar.

Figure 11. 

Principal component analysis of relative morphometric characters of the Capoeta razii sp. n. (+) C. fusca (•) and C. capoeta (◾) populations.

Figure 12. 

Correspondence analysis of meristic characters of the Capoeta razii sp. n. (+) C. fusca (•) and C. capoeta (◾) populations.

Authors wish to thank P. Rahimi, D. Corona-Santiago, P. Jalili and T. Hosseinpour for assistance in the laboratory and fish collection, and E. Elahi for proofreading this work. We thank the anonymous reviewers for their meticulous reading of our manuscript and their insightful comments and recommendations. This research was funded by Tehran University and the Spanish Ministry of Economy and Competitiveness (project number CGL2016-75262-P).