Genus Schizocypris
Regan, 1914

This genus of medium-sized snow trouts contains only 2 species found in Pakistan, Afghanistan and Iran. Coad and Keyzer-de Ville (2005) revised the genus.

It is characterised by a rounded and moderately elongate body, scales small but larger near the shoulder region, belly scaleless, a wide and transverse mouth with the snout projecting, no barbels or barbels vestigial, pharyngeal teeth with a flat tip unlike Schizothorax and a formula of 2,3,4-4,3,2 rather than 2,3,5-5,3,2 as in Schizothorax, dorsal and anal fins short but 6 branched anal fin rays not 5 as in related genera in the same area, dorsal fin with a strongly serrated spine, scales in the vent region are split and enlarged to flank the urogenital region, and radii are on all scale fields.

Rainboth (1981) includes Capoeta trutta, Capoeta fusca and Capoeta nudiventris (= C. fusca) in this genus but this is incorrect. These species show some enlargement of scales around the anus and anal fin region but it is not as marked and definitive as in true Schizocypris and other characters of the genus are absent.

Schizocypris altidorsalis
Bianco and Banarescu, 1982

Common names

gorgak (= small wolf), anjak or khaju (A. A. Pasand, pers. comm., 5 November 2000 but see under Schizothorax zarudnyi and S. pelzami).

Systematics

Schizocypris brucei, non Regan, 1914 (Annandale and Hora, 1920) is a synonym. Schizocypris brucei Regan, 1914 is thus restricted to the Gomal River drainage in the Indus River basin of Pakistan (originally described from the Wana Toi, a Gomal River tributary). A third species in the genus Schizocypris is S. ladigesi Karaman, 1969 from the Kankai River, also in the Indus River basin.

Kähsbauer (1964) reports a hybrid between Schizothorax schumacheri and Schizopygopsis stoliczkae from Sistan which may in fact be this species.

The holotype of Schizocypris altidorsalis is in the Istituto di Zoologia dell'Universitá di L'Aquila, Italy under IZA 8169 and is 73.7 mm standard length (my measurment) (Bianco and Banarescu, 1982). The type locality is "Nahr-Taheri near Zabol, Seistan". Paratypes include 5 fish from the type locality under IZA 7841, 35-65 mm standard length (4 fish seen by me, 35.4-62.0 mm standard length) with further specimens in the Institutul de Stiinte Biologice, Bucuresti, Romania (ISBB 3136). Three paratypes, 68-73 mm standard length, from "Rud-Sistan, 8 km from Zabol, Seistan" are under IZA 7844 (69.9-74.3 mm standard length measured by me) with further specimens under ISSB 3137. Two paratypes from the Nahr Taheri are in the Zoologischen Instituts und Zoologischen Museums der Universität Hamburg (ZMH 6091, 77.2-81.9 mm standard length) (Wilkens and Dohse, 1993; examined by me), 2 paratypes are in the American Museum of Natural History, New York (AMNH 40952), 1 paratype is in the Muséum national d'Histoire naturelle, Paris (1982-1018), 1 paratype is in the United States National Museum, Washington (USNM 227928), 2 paratypes are in the Academy of Natural Sciences, Philadelphia (ANSP 150977), and 2 paratypes are in CMNFI 1982-0368 (formerly IZA 7841).

Syntypes of Schizocypris brucei are in the Natural History Museum, London under BM(NH) 1913.4.15:100-109 (10 fish) and in the Zoological Survey of India, Calcutta under ZSI F9832/1 (1) (Menon and Yazdani, 1968; Eschmeyer et al., 1996).

Berg (1949) advanced the possibility that this species is the juvenile of Schizothorax zarudnyi since barbels and scale cover develop with age. However the tooth formula is very distinctive as is the anal fin branched ray count and lack of barbel development at all sizes in S. altidorsalis (Coad and Keyzer-de Ville, 2005).

Key characters

This species is characterised by a very high dorsal fin with a strongly denticulated spine. The spine is longer than the head and the denticles easily catch the skin when the fish are handled. This is particularly true of small fish, larger ones are not so snaggly. Bianco and Banarescu (1982) give values for spine length of 24.4-29.8% of standard length in altidorsalis, 19.4-20.4% in brucei, and 14.7-19.5% in ladigesi. For 35 altidorsalis 66.1-175.1 mm standard length examined here, spine length is 23.3-31.3% of standard length and 14.0-18.5% for 20 brucei 102.3-170.8 mm standard length. Dorsal spine length in head length is 0.7-0.9, mean 0.9 for altidorsalis, 1.2-1.6, mean 1.4 for brucei (see also below). Scales in the lateral line are 87-96 (brucei has 74-81 and ladigesi 78-88) according to Bianco and Banarescu (1982). Specimens examined by me have lateral line counts of 81-95, mean 87.4 for 60 altidorsalis and 73-91, mean 79.6 for 56 brucei, showing some overlap but scales are definitely smaller on average in altidorsalis.

Bianco and Banarescu (1982) describe the body as mostly scaled except on the anterior part of the breast (scaled on the mid-line of the back in front of the dorsal fin as in ladigesi, naked in brucei), and scales embedded on most of the body except the caudal peduncle and the lateral line; but see below.

Morphology

Dorsal fin unbranched rays 4, branched rays 7-8, anal fin unbranched rays 3, branched rays 5-6, pectoral fin rays 14-20, pelvic fin rays 7-9, lateral line scales 82-96, total gill rakers 24-30, reaching the third raker below when appressed in large fish but only one raker below in small fish, pharyngeal teeth usually 2,3,4-4,3,2(16) with variants 2,3,4-4,3,3(1), 2,3,5-4,3,2(2) and 2,3,5-4,4,2(1), and total vertebrae 43-45. Since spines are often broken off, the height of the dorsal fin can be measured as the longest branched ray. For this species it is 16.5-28.8% standard length (mean 24.3, 60 fish) while in S. brucei, the taxon fish in Sistan were formerly assigned to, it is 11.6-20.0% (mean 16.8, 56 fish), clearly distinguishing these species.

Scales are regularly arranged over most of the body. In some fish, scales near the tail are difficult to distinguish. Shoulder scales are moderately large anteriorly above the lateral line and decrease in size posteriorly. The back is naked in a narrow band for a short distance anterior to the dorsal fin (not so according to Bianco and Banarescu (1982) but visible in fish examined by me). Flank scales are small but those at the dorsal fin base are a little larger. Lateral line scales are larger than those on the flank but only on the anterior lateral line. The breast is scaleless according to Bianco and Banarescu (1982) but is scaled on the breast in large specimens and some small ones too. There is a pelvic axillary scale. The scale focus is anterior with radii on all fields and in overall shape is oval to rounded. Radii are found on all fields but are few in number (15).

The mouth is inferior, transverse, and slightly arched. The lower lip is developed only laterally. The lower jaw is covered by a horny sheath in some specimens, lost in others. There are usually no barbels (n = 105) although one fish, 70.1 mm standard length, had a minute pair of barbels hidden in the lip grooves and two other fish of similar size had respectively a single right and a single left minute barbel. S. brucei has small but protruding barbels on both sides in 15 fish, a left barbel only in 3 fish, a right barbel only in 5 fish and no barbels in 8 fish.

The gut is very elongate and complexly coiled. The anterior main row pharyngeal tooth is peg-like while the rest are spatulate with a deep central groove and crowns flared on each side of the groove.

Meristics for Iranian specimens are:- dorsal fin branched rays 7(2) or 8(38); branched anal fin rays 5(1) or 6(39); pectoral fin branched rays 14(1), 16(11), 17(23), 18(4) or 20(1); pelvic fin branched rays 7(1), 8(35) or 9(4); lateral line scales 81(1), 82(2), 83(3), 84(4), 85(6), 86(8), 87(10), 88(7), 89(5), 90(4), 91(3), 92(3), 93(3) or 95(1); total gill rakers 24(1), 25(4), 26(5), 27(10), 28(12), 29(6) or 30(2); pharyngeal teeth 2,3,4-4,3,2(16), 2,3,4-4,3,3(1), 2,3,5-4,3,2(2), or 2,3,5-4,4,2(1); and total vertebrae 43(16), 44(33) or 45(11).

Sexual dimorphism

Unknown.

Colour

The back is bluish and the flanks and belly are silvery. The flanks may have a few small to numerous black spots.

Size

Reaches 17.5 cm standard length.

Distribution

This species is endemic to the Sistan basin of Iran, and presumably adjacent Afghanistan (Bianco and Banarescu, 1982; J. Holčík, in litt., 1996). The distribution of this species (as S. brucei) in Khorasan and Gorgan reported by Wossughi (1978) is incorrect.

Zoogeography

A relative of other schizothroacine species found along the mountain chain from Iran to China. See also the genus Schizothorax.

Habitat

Occurs in a wide range of habitats from ditches to hamuns. Reported from pools in dry river beds and still, reedy channels in Sistan. E. Penning (pers. comm., 28 July 2005) states that this was the dominant fish species in Hamun-e Puzak and Hamun-e Saberi in April 2005 after a dry period when the hamuns flooded at the end of February. The fish enter the flooding hamuns from the upstream parts of rivers. In July, water levels fell from1-2 m to less than 1 m and this species was absent, presumably having returned to the more permanent rivers. They were also observed swimming up a fish staircase at the Sistan Dam.

Age and growth

Unknown.

Food

The principal food is aufwuchs and detritus as evidenced by the sectorial mouth and elongate gut. Gut contents are a fine mush. E. Penning (pers. comm., 28 July 2005) observed filamentous algae in the gut.

Reproduction

Most fish examined by me were young and no data on reproduction is available. E. Penning (pers. comm., 28 July 2005) noted that fish at 20-30 cm caught in April 2005 had eggs 1 mm in diameter and were approaching or ready for spawning.

Parasites and predators

Jalali et al. (1995) describe a new species of monogenean, Dactylogyrus schizocypris, from fish taken in the Chahnimeh water reservoir near the Hamun Lake in Sistan.

Economic importance

Individual fishermen caught 5-10 kg per day of this species in 2005 although they considered individuals as small and catches very low. Fish were 10-20 cm long with some larger ones at 20-30 cm (E. Penning, pers. comm., 28 July 2005).

Conservation

Further knowledge of biology is needed to assess conservation status.

Further work

The biology of this species needs study.

Sources

Type material: See above, Schizocypris altidorsalis (IZA 8169, IZA 7841, IZA 7844, ZMH 6091 and CMNFI 1982-0368).

Iranian material: CMNFI 1979-0072, 2, 120.8-162.9 mm standard length, Sistan, river near Zabol (ca. 30º58'N, ca. 61º28'E); CMNFI 1979-0223, 1, 19.9 mm standard length, Sistan, ditch south of Lutak (30º45'N, 61º24'E); CMNFI 1979-0224, 13, 48.2-77.5 mm standard length, Sistan, Hirmand River effluent (30º53'N, 61º27'E); CMNFI 1979-0225, 1, 147.7 mm standard length, Sistan, Hirmand River effluent (30º58'N, 61º28'E); CMNFI 1979-0226, 107, 60.0-82.5 mm standard length, Sistan, pool east of Kuh-e Khajeh (30º57'N, 61º17'E); CMNFI 1979-0228, 16, 18.1-73.8 mm standard length, Sistan, ditch 1 km from Zabol (31º02'N, 61º31'E); CMNFI 1979-0229, 11, 61.0-84.9 mm standard length, Sistan, ditch 5 km from Zabol (31º03'N, 61º33'E); CMNFI 1979-0231, 2, 17.5-19.9 mm standard length, Sistan, irrigation jube 3 km from Zabol (31º01'N, 61º32'E); CMNFI 1979-0232, 23, 41.8-78.8 mm standard length, Sistan, irrigation ditch 11 km from Zabol (30º58'N, 61º36'E); CMNFI 1979-0233, 2, 66.0-71.5 mm standard length, Sistan, irrigation ditch 15 km from Zabol (ca. 30º57'N, ca. 61º38'E); CMNFI 1979-0234, 15, 13.9-82.4 mm standard length, Sistan effluent of the Hirmand River near Zahak (30º54'N, 61º40'E); CMNFI 1979-0236, 1, 14.4 mm standard length, Sistan, irrigation ditch 27 km from Zabol (ca. 30º52'N, ca. 61º22'E); CMNFI 1979-0237, 5, 21.4-72.1 mm standard length, Sistan, irrigation ditch 18 km south of Zabol (30º53'N, 61º27'E).

Comparative material: USNM 182276, 5, 95.7-153.1 mm standard length, Afghanistan, Arghandab Reservoir (ca. 31º51'N, 65º55'E); USNM 182277, 1, 159.7 mm standard length, Afghanistan, Arghandab River at Kandahar (ca. 31º35'N, 65º45'E); USNM 182281, 3, 71.2-79.9 mm standard length, Afghanistan, Lashka-dah, Helmand River (ca. 31º35'N, ca. 64º21'E); USNM 182282, 5, 142.1-159.4 mm standard length, Afghanistan, Laskha-dah area (ca. 31º35'N, ca. 64º21'E); ZMUC 261629-34, 6, 131.4-203.7 mm standard length, Afghanistan, Sistan, Feyzabad (31º28'N, 61º31'E).

Material of Schizocypris brucei and S. ladigesi, nominal species not found in Iran, are listed in Coad and Keyzer-de Ville (2005)

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