Mystus cyrusi, a new species of bagrid catfish (Teleostei: Bagridae) from Middle East Author Esmaeili, Hamid Reza Ichthyology and Molecular Systematics Research Laboratory, Zoology Section, Department of Biology, School of Science, Shiraz University, Shiraz, Iran. Author Sayyadzadeh, Golnaz 0000-0003-0758-6502 Department of Biology, Faculty of Sciences, Lorestan University, 6815144316 Khorramabad, Iran. g. sayyadzadeh 92 @ gmail. com; https: // orcid. org / 0000 - 0003 - 0758 - 6502 g.sayyadzadeh92@gmail.com Author Zarei, Fatah 0000-0001-5552-4301 Ichthyology and Molecular Systematics Research Laboratory, Zoology Section, Department of Biology, School of Science, Shiraz University, Shiraz, Iran. & fataahzarei @ gmail. com; https: // orcid. org / 0000 - 0001 - 5552 - 4301 fataahzarei@gmail.com Author Eagderi, Soheil Department of Fisheries, Faculty of Natural Resources, University of Tehran, Karaj, Iran. Author Mousavi-Sabet, Hamed Department of Fisheries, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran. text Zootaxa 2022 2022-02-14 5099 3 325 343 journal article 20691 10.11646/zootaxa.5099.3.2 c35c4daf-f2d9-4bef-bc2c-2ae2ab7c9c7f 1175-5326 6078415 FB28F74A-DD16-48D7-9A1A-F5675886DFE4 Mystus cyrusi , new species ( Figs. 2–7 ) Holotype . Female , ZM-CBSU J2901, 94.2 mm SL, Iran : Fars prov. : Darab city, Forg region , Qalatooyeh (Ghalatooye) village , Qalatooyeh Spring , Kol River drainage, 28°10’16.8”N , 55°14’42.5”E . Paratypes . ZM-CBSU J2902, 4, 65–92 mm SL, same data as holotype. —ZM-CBSU J2906, 3, 79–98 mm SL, Fars prov. : Darab city, Qalatooyeh region , Kol River drainage, 28°10’14.75”N , 55°14’59.90”E .— ZM-CBSU J2909, 5, 68–98 mm SL; Iran : Fars prov. : Darab city, Forg region , Qalatooyeh village , Qalatooyeh Spring , Kol River drainage, 28°10’16.8”N , 55°14’42.5”E . — ZM-CBSU J2914, 2, 71–95 mm SL, Fars prov. : Darab city, Golabi spring, Kol River drainage, 28°47’14.72”N , 54°22’14.93”E . TABLE 2. List of species used in this study from GenBank and ZFMK including accession numbers.

Genus/Species	Locality	Genbank	Reference
Mystus albolineatus	Southeast Asia	KF824809	Unpub. GenBank record
Mystus albolineatus	Southeast Asia	KF824811	Unpub. GenBank record
Mystus atrifasciatus	Southeast Asia	KF824799	Unpub. GenBank record
Mystus atrifasciatus	Southeast Asia	KF824801	Unpub. GenBank record
Mystus bleekeri	Anchinal River, Harda, India	JX983371	Khedkar et al. (2014)
Mystus bleekeri	Barna River, Barna Ghat, India	JX983376	Khedkar et al. (2014)
Mystus bocourti	Thailand	EU490863	Sullivan et al. (2008)
Mystus bocourti	Thailand	MK448116	Unpub. GenBank record
Mystus carcio	Dhaka, Bangladesh	MK572336	Rahman et al. (2019)
Mystus carcio	Dhaka Bangladesh	MK572339	Rahman et al. (2019)
Mystus cavasius	NW Ghats, Prayag Chikhali, India	KX946714	Patil et al. (2018)
Mystus cavasius	Arunachal Pradesh, India	MT812136	Unpub. GenBank record
Mystus dibrugarensis	Tamil Nadu state, India	KF824803	Barathkumar & Thangaraj (2020)
Mystus dibrugarensis	India	KF824804	Unpub. GenBank record
Mystus gulio	Gujarat, Estuary, Narmada, Bharuch, India	KF214302	Khedkar et al. (2014)
Mystus gulio	India	MK359910	Unpub. GenBank record
Mystus malabaricus	Ganges and Brahmaputra river systems, India	HQ219113	Lakra et al. (2016)
Mystus malabaricus	India	MT997684	Unpub. GenBank record
Mystus montanus	Ganges and Brahmaputra river systems, India	HQ219129	Lakra et al. (2016)
Mystus montanus	Ganges and Brahmaputra river systems, India	HQ219130	Lakra et al. (2016)
Mystus mysticetus	Thailand	MK448108	Unpub. GenBank record
Mystus mysticetus	Thailand	MK448190	Unpub. GenBank record
Mystus ngasep	Churachandpur, Manipur, India	KJ909391	Unpub. GenBank record
Mystus ngasep	Northeast India	MG736528	Barman et al. (2018)
Mystus nigriceps	Jawa Barat, West Java, Indonesia	KU692650	Dahruddin et al. (2017)
Mystus nigriceps	Jawa Timur, East Java, Indonesia	KU692657	Dahruddin et al. (2017)
Mystus oculatus	Western Ghats, India	HQ009492	Unpub. GenBank record
Mystus oculatus	Western Ghats, India	HQ009493	Unpub. GenBank record
Mystus pelusius	Urganli, Tigris, Turkey	Ex51H1*	ZFMK-deposited record
Mystus pelusius	Urganli, Tigris, Turkey	Ex51G12*	ZFMK-deposited record
Mystus pelusius	Devegecidi Dam, Tigris, Turkey	KJ553786	Geiger et al. (2014)
Mystus pelusius	Devegecidi Dam, Tigris, Turkey	KJ553996	Geiger et al. (2014)
Mystus pelusius	Devegecidi Dam, Tigris, Turkey	FSJF 2953*	ZFMK-deposited record
Mystus prabini	Devegecidi Dam, Tigris, Turkey	FSJF 2953-2*	ZFMK-deposited record
Mystus rhegma	Siem Reap, Cambodia	JQ343984	Duan et al. (2019)
Mystus rhegma	Siem Reap, Cambodia	NC_023223	Duan et al. (2019)
Mystus singaringan	Jawa Timur, East Java, Indonesia	KU692659	Dahruddin et al. (2017)
Mystus singaringan	Jawa Timur, East Java, Indonesia	KU692660	Dahruddin et al. (2017)
Mystus tengara	India	FJ459429	Unpub. GenBank record
Mystus tengara	India	FJ459519	Unpub. GenBank record
Mystus vittatus	Uttarakhand, Poanta Sahib, India	KR809744	Thapliyal et al. (2015)
Mystus vittatus	Ranganadi River, Arunachal Pradesh, India	MH156941	Pandey et al. (2020)
Mystus wolffii	Kambas National Park, Lampung, Indonesia	MN243470	Ariyanti et al. (2021)
Mystus wolffii	Kambas National Park, Lampung, Indonesia	MN243483	Ariyanti et al. (2021)
Schizothorax esocinus	Azad Jammu and Kashmir, Pakistan	KU317702	Khan et al. (2021)

*ZFMK (Zoologisches Forschungsmuseum Alexander Koenig)-deposited COI sequences. FIGURE 1. Bayesian and Maximum Likelihood phylogeny reconstructed based on COI sequences. The values besides the branches before and after a slash are BI posterior probability and ML bootstrap values, respectively. TABLE 3. Estimates of K2P genetic divergence (%) found in the COI barcode region between the studied Mystus species

M. cyrusi	M. pelusius	M. carcio	M. vittatus	M. malabaricus M. mysticetus		M. atrifasciatus M. nigriceps		M. oculatus	M. cavasius	M. wolffii	M. ngasep	M. singaringan M. bocourti		M. albolineatus M. prabini		M. bleekeri	M. tengara	M. dibrugarensis M. gulio		M. montanus	M. rhegma
M. cyrusi	0
M. pelusius	4.6	0
M. carcio	14.3	13.9	0
M. vittatus	17.4	16	9.2	0
M. malabaricus	15.4	17	11.4	12.9	0
M. mysticetus	17.8	18.2	13.9	12.9	13.3	0
M. atrifasciatus	20.3	21.3	18.7	20.4	21.1	18.8	0
M. nigriceps	16.8	17.7	14.1	14.1	17.3	14.7	14.3	0
M. oculatus	14.2	14.7	14	13	15.5	15.3	20.1	17.2	0
M. cavasius	16.7	17.2	15.8	16.2	16.9	14.4	19.4	15.9	12.5	0
M. wolffii	13.1	13.2	15.4	16.2	15.3	17	20.8	16.6	14.4	13.5	0
M. ngasep	14.1	14.1	16.1	15.6	16.1	15.3	20.1	17.6	14.4	16.5	14.9	0
M. singaringan	11.6	13.3	15.2	18	16.8	18.8	22	17.2	15.6	16.1	14.7	14.2	0
M. bocourti	14.5	13.6	15.1	17.4	17.8	16.9	23.5	18.1	15.1	16.9	14.4	14.7	15	0
M. albolineatus	13.6	14.6	15.5	16.8	18.7	15.6	18.9	16.7	12.6	11	13.3	15.8	15.1	15	0
M. prabini	15.3	16.1	16.8	16.6	18.2	16.8	22.6	19.7	15.6	16.1	17.6	13.2	16.3	13.7	14.9	0
M. bleekeri	13.4	13.5	13.9	14.8	15.4	16.1	19.9	16.7	12.5	14	13.4	12.9	14.1	11.7	10.6	9	0
M. tengara	18.8	18.2	18.3	16.8	19.6	19.5	23.9	18.3	15.5	17.6	16.8	18	20.7	16.4	17.3	17	16.2	0
M. dibrugarensis	17.5	18.8	20.1	21.1	20	20.3	24.7	19.4	16.9	17.9	18	19	20	18.7	11.8	18.8	17.4	19.3	0
M. gulio	16.3	17.7	17.1	18.4	16.6	18	23.3	17.7	16.2	15.9	15.8	17.7	18.1	16.5	15.8	16.3	15.6	19.1	10	0
M. montanus	26.5	25.6	26.2	25.4	25.6	27	32.5	29.2	24.2	27.2	24	23.5	25.8	26.1	25.2	24.5	22.8	26.8	23.5	26.2	0
M. rhegma	18	18	14.3	13.9	13.5	4	17.9	14.3	15.7	15	17.2	14.6	17.4	16.6	16.7	17.4	16.5	19.5	21.6	19.3	27.9	0

Diagnosis. Mystus cyrusi belongs to a group of species having a long adipose-fin base and short maxillary barbel and lacking a caudal spot. Mystus cyrusi is distinguished from M. pelusius , the only other species of the genus in the Tigris-Euphrates River system in the Middle East, by a combination of characters: maxillary barbel short, not reaching to beyond of pelvic fin (vs. extends as far as anal fin in some females in M. pelusius ), smaller adipose-fin base (30.8–37.4% SL), and with a steeper sloping at its origin (vs. longer, 37.6–45.6% SL and with a more gently sloping in M. pelusius ), greater head depth (16.64–21.9% SL vs. 12.6–16.59% SL in M. pelusius ), greater caudalpeduncle depth (10.3–12.5% SL vs. 8.7–10.5 in M. pelusius ) and fewer total gill rakers (12–14 with a mode of 12 vs. 14–17 in M. pelusius ). Description. See figures 2–4 for general appearance and Table 4 for morphometric data. Body short or moderately elongated, rounded anteriorly and compressed posteriorly, dorsal profile slightly convex, rising steeply from tip of snout to dorsal-fin origin, ventral profile almost straight. TABLE 4. Morphometric data of Mystus cyrusi, ZM-CBSU J2901 , 15, n=15.

Character	Min.	Max.	Mean	SD
Standard length (mm)	106.6	203.4	173.9	21.3
In percent of head length
Head length	20.5	24.5	22.5	1.0
Head depth	12.6	16.6	14.3	0.9
Head width	16.5	19.4	17.9	0.8
Predorsal length	29.0	35.0	31.9	1.4
Postdorsal length	68.5	78.7	73.9	2.6
Dorsal length	12.4	15.9	14.1	0.8
Anal length	9.6	12.9	11.2	1.1
Pectoral length	16.5	20.9	18.9	1.3
Pelvic length	10.3	15.0	12.4	1.2
Preanal length	59.8	68.3	63.5	2.1
Prepelvic length	41.5	48.5	45.7	1.7
Distance between pectoral and pelvic-fin origins	25.1	29.9	28.1	1.5
Distance between pelvic and anal-fin origins	13.0	21.5	18.3	1.8
Maximum body depth	20.0	25.6	22.8	1.4
Depth of caudal peduncle	8.7	10.5	9.6	0.6
Length of caudal peduncle	24.9	28.1	26.5	0.8
Adipose-fin length	37.6	45.6	41.0	2.2
Adipose-fin depth	4.1	6.7	5.6	0.6
In percent of standard length
Head depth	60.6	69.8	63.5	2.8
Head width	75.1	83.0	79.6	2.2
Snout length	36.9	44.8	41.9	1.5
Postorbital distance	38.6	46.0	43.7	1.9
Interorbital width	23.9	33.6	29.1	2.2
Eye diameter	15.0	20.2	16.8	1.2
Nasal barbel	44.9	60.2	52.7	4.3
Maxillary barbel	182.9	288.4	232.9	27.4
Inner mandibular barbel	93.4	136.1	114.1	12.2
Outer mandibular barbel	62.3	82.8	68.4	5.3

FIGURE 2. Mystus cyrusi, ZM-CBSU J2901 , holotype, 94.2 mm SL; Iran: Ghalatooye (Qalatooyeh) Spring, Kol River drainage. Head short and flattened. Snout obtuse. Mouth subterminal and transverse. Eyes anteriorly situated, not visible from below ventral surface of head, moderately large with free circular margins. Four pairs of barbels, one each of maxillary and nasal and two of mandibular. Nasal barbel extend back to eye, maxillary barbel short, not reaching to beyond of pelvic fins (extending to vertical through third or fourth dorsal-fin ray, in some specimens reaching to origin of pelvic fin). Inner mandibular barbel not reaching to pectoral-fin base, outer one reaching. Gill openings wide, extending from post temporal to beyond isthmus. Skin smooth. Lateral line complete, midlateral in position. Total gill rakers 12–14, (mode of 12). Dorsal fin with II–III, 7 rays and a convex margin, usually anterior branch of fin rays longer than other branches; dorsal-fin spine short, straight, and slender, posterior edge without serrations. Pectoral fin with I, 7–8 rays, pectoral-fin spine stout and stronger than the dorsal spine, serrated with 8–10 antrorse teeth on the inner margin, the number increasing with size. Pectoral-fin margin straight anteriorly and convex posteriorly. Pelvic-fin origin slightly posterior to vertical through posterior end of dorsal-fin base, with I, 5 rays and slightly convex margin; tip of appressed fin not reaching to anal-fin origin. Anal fin with rays difficult to separate into branched and unbranched (perhaps I–IV, 8–10 rays). Adipose-fin origin at end of dorsal fin when appressed and ended in origin of caudal fin with free end. Adipose-fin origin starts with a steeply sloping and terminate at its highest portion. Caudal fin deeply forked; upper lobe larger than lower lobe. FIGURE 3. Mystus cyrusi , paratypes; lateral view, from the top: a, ZM-CBSU J2903, 80.2 mm SL; b, ZM-CBSU J2904, 76.6 mm SL; c, ZM-CBSU J2905, 65.2 mm SL; Iran: Kol River drainage. Sexual dimorphism. Males with slightly long genital papilla. Females with rounded genital opening ( Fig. 5 ). Coloration. Dorsal surface of head and body pale brown to olivaceous. Dark humeral spot and black spot at base of dorsal fin present. Ventral surfaces of head and body dirty white. Dorsal and anal fins with melanophores on rays and membranes and so these fins darker than other fins. Margin of adipose fin narrowly black. Caudal fin with black margin. Three (sometimes two), narrow, white stripes on flank, one along and one each above and below lateral line. Stripe below dorsal and adipose fins narrower than others. Barbels whitish, somewhat darker dorsally ( Fig. 6 ). Distribution and Habitat. Mystus cyrusi is currently known from three localities ( Fig. 7 ), Qalatooyeh ( Fig. 8 ) and Golabi Springs ( Fig. 9 ), and Shur River, Kol River drainage which flow to the Straits of Hormuz , Persian Gulf, in southern Iran . Golabi Spring has a high water temperature all year, 22.8°C was measured in August and 22.4°C in December. The water is typically clear with some green coloration. The spring pool is circular with a depth of less than 1.5 m . The bottom is pebbles, gravel or mud. Phragmitis sp. (Poaceae) and Juncus sp. (Juncaceae) are the dominant riparian vegetation. The spring run is short and has a moderately swift flow, emptying into cemented channels being used for agricultural purposes. Conservation. Mystus cyrusi occurs in low numbers. Hence, care should be taken to conserve the populations. Drought and introductions of alien fishes, particularly Gambusia holbrooki and Neotropical convict cichlid, Amatitlania nigrofasciata (see Esmaeili et al. 2013 ), are major threats to this endemic fish species. Etymology. The species is named for Cyrus the Great, king of Persia .