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Southeast Ecological Science Center
Channa punctata (Bloch, 1793)
After Bloch, 1793; images reversed from original pl. 358
After Munro, 1955
After Bleeker, 1878
Original description: Ophicephalus punctatus Bloch, 1793:139, pl. 358. Naturgeschichte der Auslndischen Fische, 7:i-xiv + 1-144, pls. 325-360. Type locality: rivers and lakes of Malabar coast, southwestern India. Syntype: ZMB 1394.
Synonyms: Ophicephalus karruwey Lacepde, 1801:551-552.
Common names: spotted snakehead; green snakehead; dolla or daula (Pakistan); taki, lata (West Bengal, India); phool-dhok (Bihar, India); duloora, daula (Punjab, India); soal (Jammu, India); gorissa or godissa (Orissa, India); matta-gudisa, burada-matta (Andhra Pradesh, India); korava-patti (Tamil Nadu, India); kayichal, arracan (Kerala, India); korava, juchi, belikkorava (Karnataka, India); (Talwar and Jhingran, 1992); cheng (northern Bengal, India; Shaw and Shebbeare, 1938); mada kanaya (Sri Lanka; Pethiyagoda, 1991).
Native range: Kabol (Kabul) River basin, Afghanistan, eastward through Khyber Pass into Indus River basin, Pakistan; rivers of the plains of India; Sri Lanka; southern Nepal (Edds, 1986a,b, 1993; Shrestha, 1990; Pethiyagoda, 1991); Bangladesh; Myanmar; eastward to Yunnan Province, southwestern China (Coad, 1981; Talwar and Jhingran, 1992). Musikasinthorn (1998) reported that this species is not present in Myanmar (replaced by Channa panaw in the Ayeyarwaddy (=Irrawaddy) and Sittang River basins), and reports from Yunnan Province, China, are probably misidentifications. He further stated that the eastern terminus of the range of C. punctata is the Ganges-Brahmaputra River basin. Jhingran (1984) lists this species as absent from Sri Lanka, but Pethiyagoda (1991) and Devi (1992) included Sri Lanka within its native range.
Introduced range: Smith (1950) reported this species from the vicinity of Delagoa Bay, Maputo, southern Mosambique, considered an introduction from Asia (Teugels and others, 1986). Jim Cambray, Albany Museum, Grahamstown, South Africa (personal commun., 2001) located the specimen (AM/G3714) and provided a digital photograph to us. It appeared to be a specimen of Channa striata rather than C. punctata. We borrowed the specimen through Jim Cambray and confirmed that it is C. punctata. Paul Skelton (Rhodes University, Grahamstown, South Africa; personal commun., 2001) reported the specimen as having come from the Museum in Lourenco Marques, Mozambique, and added that no other snakehead has been found or reported from that area since the Smith (1950) record. This indicates that snakeheads are not established in southern Africa.
Size: To 30-31 cm (Bardach and others, 1972; Talwar and Jhingran, 1992).
Habitat preference: Stagnant waters and muddy streams on plains of Pakistan and India, and abundant in muddy waters up to 600 m (Talwar and Jhingran, 1992). Shaw and Shebbeare (1938) recorded the species from “muddy or clear streams and ponds from 2,000 feet” (610 m) “downwards.” Quayyum and Qasim (1962) described preferred habitat in India as ponds with "a swampy bottom" and abundant aquatic vegetation, as well as ponds with sand or gravel substrate and no vegetation; they added that "large numbers can live together in a small body of water." Kumar and Mittal (1993) found habitat preferences included open water to very dense masses of vegetation in Keoladeo National Park, Bharatpur, Rajasthan, north-central India. This species is reported to tolerate a wide range of pH levels with 100 percent survival over 72 hours from pH 4.25 to 9.4 (Varma, 1979). It is unable to tolerate salinities above 6 ppm (Mansuri and others, 1979). Nevertheless, Khora and Rao (1994) recorded this snakehead as present and of commercial importance in Bahuda Estuary, Ganjam District, Orissa, India; this estuary drains into the Bay of Bengal.
This airbreather can live indefinitely without rising to the surface if water is well oxygenated (6.0 ml/L and above), but will die within 2-3 hours at an O2 level of 2.79 ml/L if access to the surface is prevented (Pandey and Chanchal, 1977).
Temperature range: The native range extends from about 34o N southward to about 7o N and altitudes up to 1,830 m, suggesting the species can exist in temperate (for example, Kabol River basin of Afghanistan) to tropical regions. Jain and Garg (1984) provided an upper lethal limit of 40 oC and lower limit of 9 oC for fish acclimated to 30 oC, but found seasonal differences. Those collected during summer months tolerated a high of 40 oC and a low of 2 oC, whereas those captured in winter showed an upper limit of 36 oC and a low of 4 oC.
Reproductive habits: Dehadrai and others (1973) noted that snakeheads in India are sexually dichromic and dimorphic, and during the breeding season, males and females of Channa punctata become deep yellow ventrally up to the lateral line, with many small melanophores in the ventral area of males and black blotches in females. Moreover, females have a circular genital opening whereas in males the opening is elongated.
Said to be a prolific breeder, with pairs spawning (in India) throughout the year, peaking before and during monsoon months (Jhingran, 1984; Talwar and Jhingran, 1992). Reaches sexual maturity in 1 year. Like many other snakeheads, this species builds circular nests in nearshore vegetation, and the eggs are pelagic and guarded by both parents. Most initial guarding appears to be by the female parent. Should the young be disturbed, the female follows the young and the male parent joins her, sometimes charging an intruder and sometimes leaving and swimming into deeper water, at which point the female attacks and drives away the intruder. Feeding by parents continues during protection of the young, and when one parent leaves the young, the other guards (Quayyum and Qasim, 1962). The nest, described as cup-shaped (Chacko and Kuriyan, 1947), is about 22-23 cm in diameter. Breeding typically occurs at night, and takes place twice each year (Raj, 1916). Kahn (1924) stated that this species builds elaborate tunnels to the nest through surrounding vegetation. Jhingran (1984) indicated that reproduction in ponds occurs through most of the year. The larger the parents, the more offspring they produce. Fecundity is between 2,300 to 29,600 eggs, with egg diameter peaking at slightly less than 0.5 mm. This information is in contrast to that presented by Kahn (1924) who recorded egg size as 2 mm. Khan (1924) also stated that hatching occurred in 54 hrs at 16-26 oC and 30 hrs at 28-33 oC. Protection of young continues for 15-20 days until juveniles become demersal (Quayyum and Qasim, 1962). Spawning in southern Nepal occurs from June until August (Shrestha, 1990). Lowe-McConnell (1987) gave April to July as the spawning period in Punjab Province, India, citing brood size as up to 500 individuals; guarding occurs for up to a month or until young are 10 cm long. Reddy (1979) stated that spawning occurs once per pair during July to October, with maximal spawning between July and August in Andhra Pradesh Province, southeastern India. This agrees with Bhuiyan and Rahman (1984) who reported a single annual spawning between April and August in Bangladesh. It appears that spawning season is largely correlated to active monsoonal periods. This is one of three species known to spawn in ponds lacking vascular aquatic plants (Parameswaran and Murugesan, 1976b).
Joshi and Sathyanesan (1981) reported finding stage I oocytes in testicular tissue of 2 of over 100 specimens of Channa punctata, all collected in December when the species is reproductively inactive. Ocytes were scattered through the testis and the gonads appeared to be a normal testis externally.
Feeding habits: Young (1.5-3.0 cm) feed primarily on zooplankton, with rotifers, insect, and crustacean larvae constituting most of the diet. Adults consume fishes, insects, and aquatic vegetation (Quayyum and Qasim, 1962), the latter probably ingested in the process of capturing animal prey.
The species is an opportunistic feeder. In canals and irrigation ponds near Guntur, Andra Pradesh State, India, stomach contents consisted of 13 species of small fishes with young of Channa punctata (one each) found in only three individuals, indicating that cannibalism is rare. Fish bones, scales, fin rays, etc., were common. Insects comprised the second tier of ingested food, followed by crustaceans, tadpoles, and an annelid worm. No algae were found, but parts of leaves and seeds were occasionally observed. By far, the most common food item was fishes (Reddy, 1980). In contrast, in polluted Hussainsagar Lake, Hyderabad, Andra Pradesh State, insects and their larvae were preferred (59.5 percent), followed by fishes and fish larvae (12.5 percent), annelids, algae, leaves, crustaceans, amphibians, and gastropods (Reddy and Rao, 1990). In ponds, tanks, and canals in the central delta area of River Godavari, Andra Pradesh, only 24 percent of the diet consisted of fishes, but 41.6 percent were crustaceans. Dutta (1994) found insects dominant (up to 100 percent) in young (3.1-4.5 cm in length) followed by crustaceans (up to 25 percent) and fishes, except for the months of June, July, and November when no fishes were found. All individuals above a length of 5 cm contained fishes. This study was conducted on specimens captured from Gadigarh Stream, Jammu, northern India.
Wee (1982) cited a study by Panday and Dwivedi (1974) in which it was shown that Channa punctata has well-developed olfactory organs in the nasal sacs and taste buds extending into the esophagus, concluding that this species locates food by odor. He also cited Gerald (1976b) as reporting maximal feeding activity of this species occurs at 28 oC. Food absorption efficiency was reported as 95.5 percent (Gerald, 1976a). Larger fish have a lower feeding rate than young (Gerald, 1976a).
Characters: Body elongated, mostly rounded; 4 or 5 scales between orbit and angle of preopercle, 12 or 13 predorsal scales; pelvic fins more than half the length of pectoral fins, extending to anal fin; pectoral fins plain, no vertical bands, 15-16 rays, about 75 percent of pectoral fin length; anal fin rays 28-37; dorsal fin rays 28-32, rarely 33; caudal fin rounded. Mouth large; lower jaw with 3 to 6 canines behind a single row of villiform teeth that widen to 5 or 6 rows at jaw symphysis. Predorsal scales 12; scales in lateral series 37-40; scales on top of head large, arranged in a rosette between orbits, the frontal scale of which has an open lateralis pit, forming the center of the rosette (Talwar and Jhingran, 1992; Jayaram, 1999). Life colors vary from black to pale green on dorsum and sides, ventral sides white to pale yellow, sometimes with red tinge; several dark blotches on lower sides; occasionally black spots on body and dorsal, anal, and caudal fins. Dorsal, anal, and caudal fins dark gray, sometimes with reddish edge; pectoral and pelvic fins pale orange (Talwar and Jhingran, 1992).
Commercial importance in the United States: Although occasionally listed on aquarist-oriented websites and in aquarium fish books, this species does not appear to have been important to the aquarium fish trade in North America. It is not known to have been imported for culture or live-food fish market sale.
Commercial importance in native range: Snakehead fishes in general are regarded as important fishery resources in India and elsewhere, fished commercially and some species utilized in aquaculture. Quayyum and Qasim (1962) reported this species as "the main bulk of pond fishery in the plains of northern India." Rao and Durve (1989) reported Channa punctata as one of three snakehead species fished commercially in Lake Jaisamand, the oldest reservoir in India. They are considered to be a delicacy and demand high prices (Talwar and Jhingran, 1992). Pethiyagoda (1991) noted that it is popular as a food fish in Sri Lanka and is also used as bait for catching larger snakeheads.
Environmental concerns: Because of their voracious, carnivorous feeding habits, snakeheads are regarded as pests in India due to their devastation of other fishes (Talwar and Jhingran, 1992), apparently in pond or culture situations where other desired species exist.
Comments: Banerjee and others (1988) recorded the diploid chromosome number of Channa punctata as 32. Dhar and Chatterjee (1984), however, found two groups, one with 32 and another with 34, indicating a species complex.
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