Freshwater
Fishes of Iran
Keys
The freshwater fishes of Iran can be identified using these keys, aided by the illustrations and characters in the "Species Accounts". All keys benefit from use and feed-back - please let me know if you encounter problems.
There are two sets of keys in this work. There is a general key to families (although all families are recognisable at a glance in Iran with a little experience) and a series of keys to genera and species. Genera keys and species keys may be separate if there are many genera and species, or combined in a single key if there are few.
Identification keys are based on couplets, a choice between two alternatives, e.g.
1. Mouth a large crescent; gill membranes joined
to form a free fold over the isthmus = Huso huso
Mouth small and transverse; gill membranes attached to
isthmus---> 2
2. Lower lip continuous, not split in middle;
more than 48 lateral scutes, usually 55 or more; barbels fimbriate =
Acipenser nudiventris
Lower lip interrupted in the middle; less than 51 lateral
scutes, usually less than 45 in Iran; barbels not fimbriate---> 3
If the fish has a large and crescentic mouth, then it is the fil mahi, Huso huso; if not, then the user is directed to the next couplet (2), and so on.
Ideally each couplet has a series of characters which reinforce each other and allow for any loss or damage to characters. Additionally, some characters are "key" but difficult to interpret without experience or are internal and require dissection which is not always possible. In some cases, only one character is available since it must encompass all included species below that point in the key. Since some species are difficult to identify, additional characters are given in brackets [.....]. These additional characters are not unique to the species but, in combination, help to identify the species. Some characters are illustrated in the keys; definitions are given in the Dictionary of Ichthyology.
If used properly, a key is more accurate and less time consuming than flicking through pages of text. The disadvantage of keys is that the alternative state in each couplet is not at hand if you only have one fish to examine, and a simple error can lead you widely astray. Some recognised species have overlapping counts for obvious meristic characters, although means and modes are significantly different, and differ in other, subtler ways not readily summarised in a key. Ideally a student of fishes should collect a series of individuals of different sizes and sexes from each locality, wherever conservation demands and practicality permits. A series of about 30-40 specimens allows for character variations dependent on sex and size, and on abnormalities, and also allows for comparative measurements and counts to be made. And more careful examination may reveal more than one species in the sample.
Distribution is often an important aid in assigning samples to a species. Readers should be aware however that fish farming in Iran has led to the introduction, either deliberately or by accident, of species into basins where they are not native.
The keys should not be used for countries bordering Iran which share many species but also have others not found in Iran.
The most important characters for identification are the general body shape, the number, position and size of the fins, the position and size of the mouth, whether teeth are obvious or not, the number of scales along the flank and the number of rays in various fins, among others. Although colour is often a useful guide, it can also be misleading. Fish vary their colour to match their background or for spawning rituals. In general, it is best to use several characters to identify a fish rather than relying on a single one which can easily be misleading.
Large fishes can be examined for these characters using the naked eye, but various pieces of equipment are necessary for identification of smaller species or juveniles. Hand lenses are of some use in magnifying small characters but by far the best instrument is a binocular microscope which can magnify up to 50 times. Pharyngeal teeth, fin rays and scales can be counted with ease using a microscope. Attachments can be used to take photographs or project images of structures for drawing. Measurements can be taken under a microscope on small specimens to ensure accuracy, and a microscope leaves both hands free to handle the specimen and dissecting tools or calipers. Ichthyologists develop their own techniques for manipulating light sources and specimens for making structures readily visible. I prefer to have two light sources. One of these illuminates the surface of the fish for scale counts and observation of structures. The other bounces light off a white enamel tray into the microscope and is particularly useful for counting fin rays as the light travels through the fin enabling clear distinction of rays.
Two types of forceps are very useful. A large pair (25-35 cm long) enables specimens to be taken out of a jar and sorted without immersing one's fingers. Preservative solutions will irritate the skin and contact should be minimised; some ichthyologists wash the specimen in water before handling, but this may compromise subsequent effectiveness of preservatives. Fine plastic gloves can be worn, but some people develop allergies to latex. A very fine pair of forceps with needle-like points is used to spread folded fins to see the rays and to probe and examine other structures.
Scissors are necessary for slitting the belly and these will vary in size depending on the size of the fish. Fine scissors can be useful in dissection. Very large fish may require a sharp knife or scalpel for dissection or slitting the abdomen. The slit is usually made on the right side of the fish as the left side (head to left) is used for drawings and photographs.
A needle mounted on a wooden or metal handle can be used for cleaning gill arches of debris, clearing flesh from pharyngeal arches or lifting the edges of scales to help in counting them. Most commercial dissecting needles are too blunt and a fine needle can be taped on the end.
Measurements are best made with calipers for accuracy. Dial or electronic calipers are available which measure to an accuracy of 0.1 mm, and are available in several lengths. Very large calipers are usually vernier calipers, but an accuracy of 0.1 mm for large specimens is not required, or even attainable.
Examination of minute scales, debris encrusted gill arches or
the lateral and cephalic line canals is facilitated by using compressed air
delivered through a glass tube of 1 mm diameter. The air can come from a
compressor or aquarium air pump, or even from a hand-squeezed bulb.
Key to Families
A little experience will soon make this key to families redundant as all Iranian freshwater fish families can be recognised at a glance. Separate keys are given for families with two or more species (Genera and Species link above). Only species which I have seen in Iran, examined museum material of, or have reliable literature records for, are included. The survival of breeding populations of some exotic fishes is uncertain; nonetheless these species are included here.
Drainage basins are given for families with a limited distribution; others are widespread, occuring in all or most basins. "Marine" is used here for drainages entering the Persian Gulf and Sea of Oman including the basins of the Tigris River, Gulf, Hormuz and Makran. The families under this heading are marine but have species that regularly enter fresh water in Iran. The terms Tigris River, Gulf, Hormuz and Makran are restricted here for freshwater residents.
Key characters, e.g. fin ray counts, are restricted to the Iranian species and family members from elsewhere may not key out here.
1. Seven
lateral gill openings on each side; mouth a sucking disc; no paired (pectoral or pelvic) fins =
Petromyzontidae (Caspiomyzon wagneri - Caspian Sea)
Less than seven gill openings (1 or 5) on each side; mouth
normal; at least pectoral
fins present, usually pelvic fins also ---> 2
2. Five
lateral gill slits on each side; scales placoid (small and prickle-like) =
Carcharhinidae (Carcharhinus leucas - Marine)
One gill opening on each side; scales, when present, cycloid,
ctenoid or bony scutes ---> 3
3. Body
covered with five rows of bony scutes; mouth inferior, behind long snout, with
four barbels in front of mouth = Acipenseridae (Caspian Sea)
Body without scutes; barbels, if present, not immediately in
front of mouth on a long snout ---> 4
4. Chin with
a single barbel at mid-point [no fin spines, 58 or more anal and second dorsal
fin rays] = Gadidae (Lota lota - Caspian Sea)
Chin without a barbel; ---> 5
5. Pelvic fins united to form a disc or funnel = Gobiidae (Caspian Sea,
Hari River, Marine)
Pelvic fins present or absent but not formed into a disc --->
6
7. Pelvic fins absent; body very elongate ("eel-like") ---> 8
Pelvic fins present; body not very elongate ---> 10
8.
First dorsal fin comprising 30-35 short,
sharp spines; flexible snout tip = Mastacembelidae (Mastacembelus
mastacembelus - Tigris, Gulf, Kor)
Spines lacking in dorsal fin; snout not flexible ---> 9
9. Body extremely thin; bounded by bony rings; snout tube-like; mouth minute
= Syngnathidae (Syngnathus abaster - Caspian Sea)
Body robust; covered with minute scales; snout not tube-like;
mouth large = Anguillidae (Anguilla
anguilla) - Caspian Sea)
10. First dorsal fin with either 3 or 8-12 isolated spines = Gasterosteidae
(Caspian Sea)
First dorsal fin not composed of isolated spines, spines when
present connected by a membrane --->
11
11. Nostrils each with a single pore; lateral line in two parts, the posterior one lower =
Cichlidae (Iranocichla hormuzensis - Hormuz)
Nostrils each with two pores; lateral line a
continuous line or absent --->
12
12. Eyes on same side of body; body compressed with left side lying on bottom =
Pleuronectidae (Platichthys flesus - Caspian Sea)
Eyes on opposite sides of body ---> 13
13. Blunt
grinding teeth in jaws = Sparidae (Acanthopgarus latus - Marine)
Teeth absent or, if present, sharp ---> 14
14. Jaws duck-like with strong teeth; dorsal and anal fins far back on body near
tail =
Esocidae Esox lucius - Caspian Sea)
Jaws and fins not as above --->
15
15. Barbels absent ---> 16
Barbels present ---> 19
16. First and second dorsal fins widely separate; scales cycloid ---> 17
First and second dorsal fins continuous or close
together; scales ctenoid ---> 18
17. First dorsal fin spines 5 or more
(usually 8 or more) and flexible; anal fin spines weak, 1-2 = Atherinidae (Atherina boyeri - Caspian Sea)
First dorsal fin spines 4 and very strong; anal
fin spines strong, 2-4 (usually 3) = Mugilidae (Caspian Sea, Marine)
18. Anal fin spines three or more; first dorsal fin spines rarely 11, usually 10 =
Centrarchidae (Namak Lake)
Anal fin spines one or two; first dorsal fin
spines 13 or more = Percidae (Caspian Sea)
19. Three or more pairs of barbels present; no scales or scales minute --->
20
Barbels two pairs, one pair, or absent; scales
present and well developed ---> 25
20. Four pairs of barbels present; nasal barbels present = Heteropneustidae (Heteropneustes
fossilis - Tigris River)
Three pairs of barbels present; no nasal barbels
? check this---> 21
21. A thoracic adhesive apparatus ("sucker")
present on the belly between the pectoral fins formed from longitudinal skin
folds = Sisoridae (Tigris River, Gulf)
No sucker ---> 22
22. Barbels longer than head;
no scales; strong pectoral fin spine ---> 23
Barbels shorter than head; scales minute or
absent; no pectoral fin spine
---> 24
23. Dorsal fin spineless, small and short (3-4 rays) and spineless;
anal fin elongate (> 69 rays) = Siluridae (Caspian Sea, Lake Orumiyeh, Tigris
River)
Dorsal fin with a strong spine, well-developed
(7-8 rays); anal fin shorter (6-10 rays) = Bagridae (Mystus pelusius - Tigris River)
24. = Cobitidae
= Balitoridae
25. Discrete, short adipose fin present = Salmonidae
(Caspian Sea, Namak Lake, Lake Orumiyeh)
No adipose fin ---> 26
26. Dorsal and anal fins long, dorsal with more than 30 rays; head snake-like --->
Channidae (Channa gachua - Hormuz)
Dorsal and anal fins short, less than 20 rays;
head normal ---> 27
27. No teeth in jaws; lateral line usually obvious ---> 28
Teeth in jaws; no lateral line pores ---> 29
28. Adipose eyelid present; branchiostegal rays 4; alar scales on caudal fin (enlarged
scales) = Chanidae (Chanos chanos - Hormuz)
Adipose eyelid absent; branchiostegal rays 3;
alar scales absent = Cyprinidae
29. Head naked dorsally; pelvic fins under dorsal fin = Clupeidae (Caspian Sea,
Marine)
Head covered with scales dorsally; pelvic fin
bases not under dorsal fin ---> 30
30. Teeth conical; anal fin in males enlarged as a copulatory organ; females without
sheath around anterior anal fin rays; body slender = Poeciliidae (Gambusia
holbrooki)
Teeth trifid; anal fin in males normal; females
with a sheath around anterior anal fin rays; body robust = Cyprinodontidae
Keys to Genera and Species
The following keys identify species in the more speciose families and genera. Some keys identify both genera and species, others have separate keys for genera and for species within genera. Some species are similar and have overlapping meristic characters. Distribution is often an additional guide to identity. It should be noted that some species are known to have been introduced to basins outside their natural range, and the possibility exists that other species may also have been translocated.
The Gobiidae key is divided by geographical area - Caspian Sea and tributary rivers and the rivers draining to the Persian Gulf and Sea of Oman.
Keys are arranged alphabetically by family and by genera within families.
Key to the genera and species of Acipenseridae
Underside of heads of H. huso, A. nudiventris, A. gueldenstaedtii, and A. stellatus. Note that A. persicus is very similar to A. gueldenstaedtii.
1. Mouth a
large crescent; gill membranes joined to form a free fold over the isthmus =
Huso huso
Mouth small and transverse; gill membranes attached to
isthmus --->
2. Lower lip continuous, not split in middle; more than 48
lateral scutes, usually 55 or more; barbels fimbriate = Acipenser nudiventris
Lower lip interrupted in the middle; less than 51 lateral scutes (usually
less than 45 in Iranian waters); barbels not fimbriate ---> 3
3. Snout
long and narrow (more than 61% of head length); barbels closer to mouth than tip
of snout = Acipenser stellatus
Snout
shorter and broader (less than 60% of head length); barbels nearer to tip of
snout than mouth ---> 4
4. Back
golden-brown, belly yellowish-white; average body depth 12-14% of total length =
Acipenser gueldenstaedtii
Back
greyish-blue, belly white; average body depth 16.8% of total length =
Acipenser persicus
Key to the species of Balitoridae
?
1. Body without pigment, pinkish from blood visible through
skin; eyes absent or reduced to spots = Nemacheilus smithi
Body pigmented; eyes small but distinctive ---> 2
2. Well-developed crest on back behind dorsal fin ---> 3
No well-developed crest ---> 6
3. Branched dorsal fin rays modally 8 = Nemacheilus
cristatus
Branched dorsal fin rays modally 7 ---> 4
4. Sistan basin; = Nemacheilus rhadinaeus
Not in Sistan basin ---> 5
5. Body covered with scales; up to 20 cm in length =
Nemacheilus longicaudus
Body without scales or scales restricted to
caudal peduncle; up to 10 cm in length = Nemacheilus malapterurus
6. Flank pigment flowing together to form a stripe =
Nemacheilus kermanshahensis
Flank pigment spots or bars but no central stripe ---> 3
Nemacheilus angorae
Nemacheilus bampurensis
Nemacheilus bergianus
Nemacheilus brandti
Nemacheilus frenatus
Nemacheilus kessleri
Nemacheilus persus
Nemacheilus sargadensis
Nemacheilus stoliczkai
Nemacheilus cf. tigris
Key to the genera and species of Centrarchidae
These two exotic species may not have reproducing populations in Iran.
1.
Lateral line scales small, 58-81; body rounded in cross section and elongate,
maximum body depth 2.5-5.0 (usually 3.0 or more) times in body length from snout
tip to end of scales = Micropterus salmoides
Lateral line scales large, 35-50; body compressed
in cross section and deep, maximum body depth 1.7-3.0 (usually 2.5 or less)
times in body length from snout tip to end of scales =
Lepomis macrochirus
Key to the genera and species of Clupeidae
Caspian Sea species have numerous nominal subspecies and keys to these may be found in Berg (1948-1949) and Svetovidov (1952).
1. Upper jaw without a median notch, rounded when viewed from
in front; last two anal fin rays enlarged; lower jaw articulation with skull
below or anterior to posterior eye margin; Caspian Sea species ---> 2
Upper jaw with a median notch; last two anal fin rays not
enlarged; lower jaw articulation with skull behind posterior eye margin ---> 4
2. Pectoral fins pointed at tips; head short and wide (interorbital
width 16% or more of head length) ---> 3
Pectoral fins rounded at tips; head large and narrow (interorbital
width 15.5% or less of head length) = Clupeonella grimmi
3. Body and belly compressed (body depth about 21-27% of
standard length); keeled belly scales evident = Clupeonella cultriventris
Body cylindrical and belly rounded (body depth 16-19% of
standard length); keeled belly scales weakly developed = Clupeonella
engrauliformis
4. Branched pelvic fin rays 8; upper gill rakers overlap
lower gill rakers at angle of first arch; Caspian Sea species ---> 5
Branched pelvic fin rays 7; upper gill rakers not overlapping
lower gill rakers at angle of first arch; marine, entering rivers of southern
Iran = Tenualosa ilisha
5. Body deep and compressed; head large and deep,
wedge-shaped in anterior view; caudal peduncle short; pectoral fins long ---> 6
Body not deep and not compressed; head not large and deep,
not wedge-shaped in anterior view; caudal peduncle not short; pectoral fins
short ---> 8
6. Gill rakers on first arch 60 or more, thin and long, much
longer than gill filaments; teeth weakly developed = Alosa caspia
Gill rakers on first arch 45 or less, shorter, equal to
or somewhat longer than gill filaments; teeth well developed ---> 7
7. Upper and lower profiles of head straight; lower jaw
protruding and its upper edge straight = Alosa saposchnikowii
Upper and lower profiles of head rounded; jaws equal in
length and lower jaw has a crescentic upper edge = Alosa sphaerocephala
8. Gill rakers 47 or less, thick and coarse = Alosa
braschnikowii
Gill rakers 59 or more, may be thin and long but can be
coarse and short = Alosa pontica
Key to the genera and species of Cobitidae
see Berg
Key to the genera and species of Cyprinidae
The cyprinid family is the most speciose in Iranian fresh waters. Members of the family are more easily identified first to genus and then to species. Keys are then shorter and less liable to error in use. Additional characters can be listed under each genus or species which are not unique nor readily incorporated into keys but which in combination help to identify the genus or species. These additional characters are given in brackets. Monotypic genera key out to species in the generic key.
?Add petroleuciscus
1. Branchiostegal membranes not attached to isthmus; gill
rakers fused together; eyes low on side of head, below midline; suprabranchial
organ present = Hypophthalmichthys
Branchiostegal membranes attached to isthmus; gill rakers not
fused; eyes at or above midline of head; suprabranchial organ absent ---> 2
2. Serrated stiffened ray (spine-like) in the dorsal and anal
fins; dorsal fin elongate (? rays or more, usually ?); anal fin origin below
dorsal fin ---> 3
No serrated stiffened ray (spine-like) in the anal fin;
dorsal fin short to moderately elongate (?-? rays, usually ?); anal fin origin
behind dorsal fin end ---> 4
3. Barbels absent; pharyngeal teeth in one row = Carassius
Barbels present (two pairs); pharyngeal teeth in three rows =
Cyprinus
4. Eyes absent; body pink through lack of pigment; no scales
= Iranocypris typhlops
Eyes present; body pigmented; scales present, sometimes
restricted to anal area ---> 5
5. Anus and anal fin base sheathed by markedly enlarged
scales ---> 6
Anus and anal fin base not sheathed by markedly enlarged
scales ---> 8
6. Branched anal fin rays 5; scales mostly absent; pharyngeal teeth in two rows
= Schizopygopsis
Branched anal fin rays 6; scales present; pharyngeal
teeth in three rows =
Schizothorax
Schizocypris
7.
8. An adhesive disc on the underside of the head = Garra
No adhesive disc
Pelecus
mouth structure Pseudorasbora
10. naked ventral keel Abramis Alburnoides Alburnus Blicca Chalcalburnus Vimba (also put alburnoides, alburnus and chalcalburnus in another couplet)
Barbels present ---> x
Barbels absent
x. Spine in dorsal fin ---> h
No spine in dorsal fin ---> c
h. Spine smooth; mouth not sector-shaped = Barbus (partim)
Spine with teeth; mouth sector-shaped (u-shaped in young)
---> i
i. Branched anal fin rays 6, dorsal fin branched rays 10 or more; lateral line
scales ? = Cyprinion
Branched anal fin rays 5; dorsal fin branched rays 9 or less;
lateral line scales ? = Capoeta
c. Scales small, more than ?100 in lateral line = Tinca tinca
Scales larger, less than ? in lateral line ---> q
q. Anal fin branched rays 13 or more = Barilius mesopotamicus
Anal fin branched rays less than 13 ---> t
t. Dorsal fin branched rays 7; pharyngeal teeth in two rows = Gobio
Dorsal fin branched rays 8; pharyngeal teeth in one row
---> s
s. Lateral line complete = Crossocheilus
Lateral line incomplete = Hemigrammocapoeta
Acanthalburnus
Acanthobrama
Aspidoparia
Aspius
Barbus
Barilius
Capoeta
Chondrostoma
Crossocheilus
Ctenopharyngodon
Cyprinion
Garra
Gobio
Hemiculter
Hemigrammocapoeta
Leucaspius
Leuciscus
Petroleuciscus
Pimephales
Rhodeus
Rutilus
Scardinius
Tinca
Acanthobrama marmid
Alburnoides bipunctatus
Aspidoparia morar
Barilius mesopotamicus
Blicca bjoerkna
Crossocheilus latius
E Ctenopharyngodon idella
Cyprinus carpio
E Hemiculter leucisculus
Hemigrammocapoeta elegans
Leucaspius delineatus
Pelecus cultratus
E Pimephales promelas
E Pseudorasbora parva
Rhodeus sericeus
Scardinius erythrophthalmus
Schizocypris altidorsalis
Schizopygopsis stoliczkai
Tinca tinca
Vimba vimba
Key to the Species of Abramis
1. Branched anal fin rays 22-30 = Abramis brama
Branched anal fin rays 31-44, mostly 34 or more =
Abramis sapa
Key to the Species of Acanthalburnus
1. Anal fin branched rays 13-19; lateral line scales 60-85;
Caspian Sea = Acanthalburnus microlepis
Anal fin branched rays 10-13; lateral line scales 50-68;
Lake Orumiyeh = Acanthalburnus urmianus
Key to the Species of Alburnus
add Chalcalburnus
Key to the Species of Alburnoides
1. 15-20 total gill rakers in outer row on first gill arch = A. taeniatus
(not recorded in Iran but may eventually reach the Caspian Sea basin and the
Tedzhen (= Hari) River drainage of Iran from the Tedzhen River and Karakum Canal
in Turkmenistan)
5-10 total gill rakers in outer row on first gill arch ---> 2
2. Snout pointed or slightly rounded; mouth terminal or upturned, tip of mouth
cleft on level from slightly above middle of eye to upper margin of pupil; lower
jaw slightly to moderately projecting relative to upper jaw; junction of lower
jaw and quadrate on about vertical through anterior eye margin; Kor River basin=
A. qanati
Snout slightly to markedly rounded; mouth terminal to subterminal,
tip of mouth cleft on level from middle of eye to below lower margin of eye;
upper jaw slightly to moderately projecting relative to lower jaw; junction of
lower jaw and quadrate on about vertical through about middle of eye ---> 3
3. 8-11, commonly 9-10, branched anal fin rays; 7, rarely 8, branched dorsal fin
rays ---> 4
10-15, commonly 11-13, branched anal fin rays; 8, rarely 7,
branched dorsal fin rays ---> 5
4. Ventral keel completely scaled; 40-41 total vertebrae; 20-22, commonly 21,
abdominal vertebrae; Lake Orumiyeh basin = A. petrubanarescui
Ventral keel scaleless along from 1/3 to whole keel length;
38-40, commonly 39, total vertebrae; 19-20 abdominal vertebrae = A. nicolausi
(lower Tigris River system) ?more and move into key caharcter
5. Ventral keel smoothed, scaled along 1/3 to whole length = A. idignensis
(lower Tigris River system) ?more detail as to locality
Ventral keel well pronounced, almost or completely scaleless
---> 6
6. Lateral line in live and preserved fish delineated by dark pigment dots above
and below; 13-15 predorsal vertebrae; mouth terminal, tip of mouth cleft on or
slightly below middle of eye = A. eichwaldii (Caspian Sea basin)
Lateral line in live and preserved fish somewhat darker than
surrounding flank but no strong dark dots outline canal; 11-13 predorsal
vertebrae; mouth almost subterminal, tip of mouth cleft on or below lower margin
of eye; Namak Lake basin = A. namaki
Key to the Species of Chalcalburnus
1. Total gill rakers 18-25 (usually 19 or more); branched anal fin rays
12-19 (usually 13 or more); peritoneum light brown; Caspian Sea basin = Chalcalburnus chalcoides
Total gill rakers 11-18 (usually 16 or less); branched
anal fin rays 9-14 (usually 13 or less); peritoneum brown to black; outside
Caspian sea basin ---> 2
2. Lateral line scales 46-63 (usually 58 or less); Lake Orumiyeh basin = Chalcalburnus atropatenae
Lateral line scales 58-89 (usually ? or more ? see data
sheets);
Tigris, Kor and Gulf drainages =
Chalcalburnus mossulensis
1. Dorsal fin branched rays modally 8 (range usually 7-9);
lateral line scales usually 39-50 (maximum range 36-55); anal fin branched rays
usually 12-16 (maximum range 10-21); no strong mid-flank stripe = Alburnus
alburnus
Dorsal fin branched rays modally 7 (range usually 6-8);
lateral line scales usually 50-57 (maximum range 46-64); anal fin branched rays
usually 10-12 (maximum range 9-13); a strong mid-flank stripe = Alburnus
filippi
Key to the Species of *Aspius
1. Lateral line scales 62-105; anal fin branched rays 11-15,
usually 12; total gill rakers 8-11; total vertebrae 50-51; Caspian Sea basin =
Aspius aspius
Lateral line scales 91-110; anal fin branched rays 10-13,
usually 11?; gill rakers 11-14; total vertebrae 51-53; Tigris River basin =
Aspius vorax
* The distinction of these two species has not been examined recently and characters overlap, sample sizes for gill rakers and scales above in particular being very small. However they are found in separate basins.
Key to the Species of Barbus
?Teeth counts, barbel and lip shapes, scales above l.l. etc for further distinction
1. Barbels absent [scales large, 29-35 in lateral line; body
compressed; Tigris River basin; dorsal fin spine smooth, without denticulations]
= Barbus sharpeyi
Barbels present ---> 2
2. Branched dorsal fin rays 9-11, usually 10 (9 = 7.5%, 10 =
86.9%, 11 = 5.6% for 160 fish); anal fin branched rays with strong mode at 6
(99%); lateral line scales large, 38 or less and mostly 35 or less; body
compressed ---> 3
Branched dorsal fin rays with strong mode at 8 (97.5%,
only one fish with 9 rays out of 161 fish), 7 in one species; anal fin branched
rays with strong mode at 5 (100%); lateral line scales medium to small, rarely
large, 34-103, mostly 42 or more; body rounded in cross section ---> 5
3. Mouth terminal, no rounded median lobe on lower lip,
usually 2 barbels (third or fourth barbels if present minute); Tigris River
basin; Persian Gulf tributaries [scales 23-31; dorsal fin spine smooth, without
denticulations] = Barbus luteus
Mouth subterminal, rounded median lobe on lower lip, 4
barbels ---> 4
4. Lateral line scales 29-38; total vertebrae 39-40; Tigris River basin = Barbus kosswigi
Lateral line scales 24-27; total vertebrae 37-38; Tigris
River basin in A'la River= Barbus sublimus
5. Dorsal fin spine smooth, without denticulations; scales
large, 34-43 in lateral line; Tigris River basin and northern Gulf tributaries
[total gill rakers 19-22] = Barbus grypus
Dorsal fin spine with denticulations; scales medium to
small, 42-103, mostly 50 or more ---> 6
6. Head, body and fins with large, dark spots arranged
almost in a quincunx pattern; Tigris River basin = Barbus subquincunciatus
Head, body and fins without large, dark spots although
speckling may be present ---> 7
7. Head pike-shaped, tapering and depressed anteriorly
[adults very large, reputedly over 2 m long; Tigris River basin [lateral line
scales 63-78; total gill rakers 8-12] = Barbus esocinus
Head not pike-shaped ---> 8
8. Body covered with speckles ?describe size in relation to
scales/eye; widespread in Caspian Sea basin and westerrn Iran [total gill
rakers 5-13] = Barbus lacerta
Body not covered with distinctive speckles ---> 9
9. Caspian Sea and Namak Lake basins ---> 10
Persian Gulf basins (Tigris, Gulf) ---> 12
10. Lower lip with central flap; Caspian Sea basin and Namak
Lake basin [lateral line scales 74-103, usually 80 or more; total gill rakers
9-16] = Barbus mursa
Lower lip without central flap [lateral line scales
51-85, mostly 75 or less] ---> 11
11. Dorsal fin branched rays modally 7; flank colour
gradually lightens from dorsal to ventral (rarely abrupt transition as in B.
capito); predorsal length shorter than postdorsal length; Caspian Sea basin
[lateral line scales 63-85, mostly 65 or more; total gill rakers 18-21] =
Barbus brachycephalus
Dorsal fin branched rays modally 8; upper part of flank
dark, lower light and strongly contrasting; predorsal length equal to longer
than postdorsal length; Caspian Sea basin [lateral line scales 51-70, mostly 65
or less; total gill rakers 12-19] = Barbus capito
12. Total gill rakers 7-13 [Tigris River basin; lateral line
scales 57-68] = Barbus xanthopterus
Total gill rakers 14-21 [lateral line scales 60 or less]
---> 13
13. Fourth major row pharyngeal tooth large and molariform;
Tigris River and northern Gulf tributaries [47-59 lateral line scales] =
Barbus barbulus
Fourth major row pharyngeal tooth similar in size to
third, not molariform [lateral line scales 42-60] ---> 14
14. Dorsal fin origin at or ahead of pelvic fins origin;
Tigris River basin = Barbus pectoralis
Dorsal fin origin behind pelvic fins origin; Tigris
River basin = Barbus kersin
Key to the Species of Capoeta
Capoeta aculeata
Capoeta barroisi
Capoeta buhsei
Capoeta capoeta
Capoeta damascina
Capoeta fusca
Capoeta trutta
Key to the Species of Carassius
1. Lateral line scales 25-34, mostly 31 or less; gill rakers
35-54, size dependent and mostly 39 or more in adults; anal fin branched rays
modally 5; young never with dark spot on caudal peduncle = Carassius auratus
Lateral line scales 32-36; gill rakers 23-35,
mostly 31 or less; anal fin branched rays modally 6; young usually with dark
spot on caudal peduncle = Carassius carassius
Key to the Species of Chondrostoma
1. Caspian Sea basin = Chondrostoma cyri
Tigris River and Kor River basin = Chondrostoma regium
Key to the Species of Cyprinion
distribution; tabulate characters for comparison
Cyprinion kais
Cyprinion macrostomum
Cyprinion milesi
Cyprinion tenuiradius
Cyprinion watsoni
Key to the Species of Garra
?
1. Caudal fin branched rays modally 16 (85.6% for 132 fish,
range 15-17); southeastern Iran = Garra persica
Caudal fin branched rays modally 17, 16 only rarely --->
2
2. Dorsal fin branched rays modally 8 (87.1% for 534 fish,
range 6-8); southwestern Iran ? sucker structure = Garra rufa
Dorsal fin branched rays modally 7 (91.5% for 59 fish,
range 6-8) ---> 3
3. ?; Eastern Iran = Garra rossica
?; Tigris River basin = Garra variabilis
Key to the Species of Gobio
(key to subspecies of Gobio persus by A. Naseka, Zoological Institute, St. Petersburg)
1.
Body and caudal peduncle compressed
(caudal peduncle depth at anal fin insertion greater than caudal peduncle
width); well-defined spots on the dorsal and caudal fins; Tedzhen River = Gobio gobio
Body only slightly compressed and the caudal peduncle
cylindrical (caudal peduncle depth at anal fin insertion less than or about
equal to caudal peduncle width); faint spots on the dorsal and caudal fins; Lake
Orumiyeeh and Caspian Sea = Gobio persus ---> 3
3. Number of lateral line scales 40 to 42 with modes of 40 or
41; total vertebrae 37 to 40 with modes of 38 and 39; connection between the
supraorbital and infraorbital head canals usually absent; Lake Orumiyeh =
Gobio persus persus
Number of lateral line scales 41 to 45 with modes of 42
and 43; total vertebrae 38 to 42 with modes of 40 and 41;
connection between the supraorbital and infraorbital head canals usually present; Caspian Sea =
Gobio persus macropterus
Key to the Species of Hypophthalmichthys
1. Abdomen with a compressed keel extending from the breast
(pelvic fins) to the vent; pectoral fins short, not extending past the origin of
the pelvic fins; gill rakers a continuous band uniting both sides, roots fused
into a spongy mass = Hypophthalmichthys molitrix
Abdomen with a compressed keel extending from the throat
to vent; pectoral fins long, extending past the origin of the pelvic fins; gill rakers free,
no spongy mass = Hypophthalmichthys nobilis
Key to the Species of Squalius
Leuciscus cephalus
Leuciscus latus
Leuciscus lepidus
Key to the species of Petroleuciscus
Petroleuciscus persidis
Petroleuiscus ulanus
Key to the Species of Rutilus
1. Lateral line scales 47-64, mostly 55-58; swimbladder
elongate and conical or pointed posteriorly = Rutilus frisii
Lateral line scales 39-48, mostly 42-47; swimbladder
rounded posteriorly = Rutilus rutilus
Key to the Species of Schizothorax
Schizothorax intermedius
Schizothorax pelzami lips thick
Schizothorax zarudnyi lips thin
Key to the genera and species of Gasterosteidae
1. Long dorsal fin spines, numbering 3; long pelvic fin
spines, both dorsal and pelvic spines exceeding eye diameter in length; scutes
(vertical bony plates on flank) large = Gasterosteus aculeatus
Short dorsal fin spines, numbering 7-11, alternatively
sloping left and right; both dorsal and pelvic spines shorter than eye diameter; scutes small = Pungitius platygaster
Key to Persian Gulf and Sea of Oman drainage species of the Family Gobiidae
see murdy
1. Lateral series scales large, 28-36; eyes not protruding = Glossogobius giuris
Lateral series
scales minute, over 90; eyes protruding above dorsal head profile ---> 2
2. 4-5 first dorsal fin spines; anal fin base and second dorsal fin base 34% or more of
standard length; 2 canine teeth internal to the lower jaw symphysis =
Boleophthalmus dussumieri
10-14 first dorsal fin spines; anal fin base and second
dorsal fin base 27% or less of standard length; no canine teeth internal to the
lower jaw symphysis = Periophthalmus waltoni
Key to Caspian Sea genera of the Family Gobiidae
Some genera are monotypic or have only a single species in the Caspian Sea basin and so the keys terminates there. Speciose genera have separate keys below.
Note that a Rhinogobius species is recorded from the Tedzhen (= Hari) River basin in Iran as an exotic (see Gobiidae species accounts for description). This is the only goby outside the Caspian Sea basin and coastal waters of the Persian Gulf/Sea of Oman in Iran.
The following key is modified after Miller in Miller (2003):-
1. Suborbital papillae with longitudinal row a immediately below eye
and having at least one short side row; cheek with several short transverse
rows, none reaching lower eye margin; snout with longitudinal rows s1
and s2 or, if transverse interorbital and snout rows, a
perianal organ is present---> 2
Suborbital papillae in transverse rows; no row a;
snout with transverse rows s1 and s2; no
perianal organ---> 3
2. Otic transverse row tra long, from level of anterior oculoscapular
canal to near row b, and cheek transverse row descending through row d
to near row e =
Hyrcanogobius bergi
Otic transverse row tra short, distant from row b,
and no anterior cheek transverse row passing through row d =
Knipowitschia
3. Row 5i not below level of row 6i; 6i at or opposite
end of row d; scales normal; canals present or absent---> 4
Row 5i below level of row 6i; 6i
separated from posterior end of row d by row 5i; scales
non-imbricate or bony tubercles and granules or naked; no canals ---> 7
4. Anterior nostril an elongate tube hanging over lip = Proterorhinus
marmoratus
Anterior nostril elongate but not overhanging lip---> 5
5. Three rows below row b = Mesogobius nonultimus
Two rows below row b---> 6
6. Four rows before row b = Neogobius
Five rows before row b = Chasar bathybius
7. Chin barbel and cheek flap present = Benthophilus
No chin barbel or cheek flap---> 8
8. No scales in both sexes; rows 5i and 6i more or less
juxtaposed = Caspiosoma caspium
Modified scales or granules in skin (of females at
least), or body naked in males; suborbital rows 5s and 6s not
distant from other transverse rows---> 9
9. Four transverse infraorbital rows before row b; non-imbricate
scales present = Benthophiloides turcomanus
Five or six transverse infraorbital rows before row b;
skin with bony granules; snout a duck-bill shape = Anatirostrum profundorum
The following key does not use papillae and head canal characters. It is modified from Mitrofanov (2003) as translated courtesy of Dmitri Ponomarenko:- CHECK Below species against ones above
1. Body naked ---> 2
Body covered with regular ctenoid scales ---> 4
Body covered with long spikes = Benthophiloides brauneri
2. Snout narrow and long = Anatirostrum profundorum
Snout regular, not elongated ---> 3
3. Tail rounded;
body covered with sharply bordered dark spots ---> Caspiosoma caspium
Tail pointed; body without spots Benthophiloides
turcomanus
4. Anterior nostril elongated into a tube that hangs over lip
---> Proterorhinus marmoratus
Anterior nostril not as above---> 5
5. Second dorsal fin
short, with less than 12 branched rays; small fishes less than 50 mm ---> 6
Second dorsal long, with more than 12 branched rays ---> 7
6. Body covered with scales only in the posterior part; mucous canals open,
close to posterior edge of eyes; eyes directed upwards and laterally; body
without black spots but with small brownish dots;
tail rounded and symmetrical, without a dark spot at the base
---> Hyrcanogobius bergi
Scales on sides of body, with head, throat, belly and back to
second dorsal fin scaleless; eyes lateral; body darkly pigmented without
stripes; tail symmetrical without a dark spot at tail base ---> Knipowitschia
caucasica
Body fairly fully covered with scales; eyes pointed
upwards; body with dark stripes; body glassy and translucent; tail symmetrical
without a basal spot; deepwater species ---> Knipowitschia iljini
Body fairly fully covered with scales; eyes pointed upwards;
body without stripes; back with rare brownish dots; body semi-translucent; tail
asymmetrical with a dark basal spot ---> Knipowitschia longecaudata
7.
Sinciput not covered with scales (Mesogobius) ---> 8
Sinciput and occiput covered with scales ---> Neogobius
8. Up to 50 transverse scale rows; sinciput and occiput entirely bare; sides
carry oblique stripes directed forwards; colour light yellow --->Mesogobius
gymnotrachelus (included in Neogobius by some authors)
More than 70 transverse scale rows; sinciput bare, occiput
partially scaled; stripes not developed; colouration pale grey --->
Mesogobius nonultimus
60-70 transverse scale rows; sinciput and occiput bare; sides
carrying 5 black spots ---> Mesogobius nigronotatus
Key to species of the genus Benthophilus
check charactesr against text in Boldyrev abnd Bogut
The following key is modified after Pinchuk and Miller in Miller (2004) and Boldyrev and Bogutskaya (2007). It includes only those species recorded from Iran and the works cited have keys to all Caspian Sea species.
1. One or two dermal barbels
behind jaw angle; first dorsal fin with 0-2 spines, commonly 1; tubercles large and high,
not all spinous; tubercles in dorsal row 11-17, in ventral row 9-14 = B.
baeri
A dermal fold or lobe behind jaw angle (if absent, tubercles
vertically elongated); first dorsal fin spines 3-4 (rarely 2); tubercles in
dorsal row 18 or more, in ventral row 14 or more ---> 2
2. Tubercles vertically
elongated, curved and crest-like, rear edges spinulose; temporal and occipital
region without large tubercles; extremely small or no granules on head; back without brown bands ---> 3
Tubercles conical and tipped by spines; temporal and
occipital region with large tubercles; tubercles and granules on head; back with or without brown bands ---> 4
3.
Temporal and occipital region of head with granules; tubercles in dorsal row
incomplete, starting at dorsal fin origin; dermal fold at mouth angle well-developed, 1.2 times eye diameter = B. ctenolepidus
Temporal region of head naked; tubercles in dorsal row
complete, starting just behind head; dermal fold small, less than eye diameter = B. pinchuki
4. Tubercle rows distinct but tubercles relatively small (23-27,
modally 25); upper head and body
densely covered with very small granules; no dark brown bands on back ---> B.
macrocephalus
Tubercles distinct, relatively large (25-30,
modally 28); granules on temporal
and occipital area small and sparse, or if slightly larger then not forming real
tubercles; bands present on back ---> B. leobergius
Key to spawning males of the genus Benthophilus
The following key is modified after Boldyrev and Bogutskaya (2007). It includes only those species recorded from Iran and the work cited has keys to all Caspian Sea species.
1. Small and thornless tubercles on body; total vertebrae 24-27,
usually 25-26 ---> B. baeri
Body naked; total vertebrae 26-32, usually 27-31 ---> 2
2. No dark blotches on back and flanks ---> 3
Three dark blotches on back and flanks ---> 4
3. Dermal fold behind jaw angle with rounded free margin, deep and long (12-24%
head length and larger than eye diameter); caudal vertebrae 18-21, usually
19-20, total vertebrae 28-30, usually 28-29 ---> B. ctenolepidus
Dermal fold behind jaw angle triangular and small (3-11%
head length and less than eye diameter); caudal vertebrae 20-23, usually 21-22,
total vertebrae 30-32 ---> B. pinchuki
4. Upper jaw
projecting over lower jaw; precaudal vertebare 10-11, usually 11 ---> B.
leobergius
Upper jaw not projecting over lower jaw; precaudal
vertebrae 9-10, usually 9 ---> B. macrocephalus
Key to Caspian Sea species of the genus Knipowitschia
The following key is modified after Miller in Miller (2004). It includes K. longecaudata although this species has yet to be confirmed from Iran.
1. Anterior oculoscapular canals more or less separate in midline of
posterior interorbit, with pore κ double, and
canals extending anteriorly through
interorbit of variable extent, typically absent; preopercular
canal present or absent = K. iljini
Anterior oculoscapular canals united at posterior
interorbit, with a single median pore κ, and canals
extending anteriorly to pores λ; propercular canal present ---> 2
2. Posterior oculoscapular canal always absent;
males with numerous thin flank bars of varying distinction; first dorsal fin
with rear black mark at fin margin;
vertebrae modally 32-33 (range 32-35) = K.
longecaudata
Posterior oculoscapular canal usually present; males with
about 4 conspicuous flank bars; first dorsal fin with black blotch within edge
of fin; vertebrae
modally 31-32 (range 30-33, posterior oculoscapular canal
present if mode is 32) = K. caucasica
Key to Caspian Sea species of the genus Neogobius
The following key is modified after Miller and Vasil'eva in Miller (2003). It includes N. gymnotrachelus although this species has yet to be confirmed from Iran.
1. Pelvic fin anterior membrane with angular lateral lobes; lobes about
one-sixth to almost one-half width of anterior edge of membrane ---> 2
Pelvic fin anterior membrane with rounded and shallow lateral
lobes; lobes not more than one-sixth width of anterior edge of membrane, or
lacking entirely
---> 5
2. Posterior nostril markedly distant from edge of orbit; anterior nape with
cycloid scales; rear of first dorsal fin with a large dark spot = N.
caspius
Posterior nostril near edge of orbit; anterior nape with
ctenoid or cycloid scales; rear of first dorsal fin without a dark spot --->
3
3. Lateral series scales usually 49-54; lateral lobes of pelvic fin anterior
membrane small, not more than one-fifth width of rear edge; upper lip width
0.4-0.67
lateral preorbital width (lip to orbit); nape scales cycloid;
pelvic fin almost reaches the anal fin (0.9 distance) or extends beyond the anal
fin
origin = N. ratan
Lateral series scales usually 54-76; lateral lobes of
pelvic fin anterior membrane large, at least one-fifth width of rear edge; upper
lip width at least 0.6
lateral preorbital width (lip to orbit), if less than 0.75,
then nape scales ctenoid; pelvic fin less than nine-tenths distance to anal
fin ---> 4
4. Upper lip not markedly swollen, width about 0.6-0.67
lateral preorbit; interorbital distance 0.8-0.9 eye diameter; caudal peduncle
depth 0.67-0.75 length =
N. gorlap
Upper lip moderately swollen, width about 0.75 to more
than length lateral preorbit; interorbital distance 0.4-0.8 eye diameter; caudal
peduncle depth 0.75
to more than length = N. cyrius
5. Nape naked before level of preopercle = N. gymnotrachelus
Nape scaled ---> 6
6. At least anterior nape scales
cycloid; first dorsal fin with large dark spot at rear; lateral series scales
usually 49-55 = N. melanostomus
Nape scales ctenoid; first dorsal fin without large dark
spot; lateral series scales usually 55-70 ---> 7
7. Pelvic fin disc two-thirds
distance to anal fin origin; pelvic fin anterior membrane anterior lobes
shallowly convex; angle of jaw below pupil of eye; three
transverse infraorbital papillae rows below longitudinal
hyomandibular row b = N. syrman
Pelvic fin disc 0.9 to more than distance to anal fin
origin; pelvic fin membrane anterior lobes small, rounded, less than one-fifth
rear edge width; angle of jaw
anterior to orbit; two transverse infraorbital papillae rows
below longitudinal hyomandibular row b = N. fluviatilis
The following key is modified from Mitrofanov (2003) as translated courtesy of Dmitri Ponomarenko:- CHECK species below against ones above
1.
Head breadth approximately equal to depth; first dorsal fin with 6 rays,
colourless; second dorsal fin the same along its length; nostrils strongly
displaced forward so anterior nostril almost touches upper lip and
posterior nostril is far from the eye ---> N. caspius
Head breadth markedly greater than depth; first dorsal fin
with 6 rays, carrying transverse stripes, often zig-zagging ---> N. gorlap
Head breadth approximately equal to depth; first dorsal fin
with 7 rays, colourless; second dorsal fin becomes markedly lower posteriorly
---> N. bathybius
Head breadth approximately equal to depth; first dorsal
fin carrying a sharp, dark, almost black spot; first dorsal fin has 6 rays,
rarely 7; second dorsal fin slightly increases in height anteriorly ---> N.
melanostomus
First dorsal fin with 6 rays and with transverse stripes;
second dorsal fin height equal along its length; upper jaw overlaps lower jaw
---> N. ratan
Head breadth approximately equal to depth; first dorsal fin
with 6 rays and longitudinal stripes running along rays; second dorsal fin rises
towards the middle; lower jaw juts forward ---> N. syrman
Head breadth approximately equal to depth; first dorsal fin
with 6 rays, without stripes or spots; second dorsal fin gradually decreasing in
height towards rear ---> N. fluviatilis
Key to the genera and species of Mugilidae
1. Posterior end of maxilla not curved below tip of
premaxilla, but straight; jaw end on line of gape; adipose eyelid
well-developed, enclosing eye over much of anterior and posterior fields of
iris, so pupil is covered by an oval slit; pyloric caeca 2; marine = Mugil
cephalus
Posterior end of maxilla curved below tip of premaxilla,
visible behind corner of closed mouth; jaw end on below line of gape; adipose
eyelid weakly-developed, not reaching pupil of eye; pyloric caeca 6-9 ---> 2
2. Branched second dorsal fin rays 7; anal branched rays 8;
pectoral fin long, reaching dorsal fin level; Tigris River, Gulf = Liza abu
check caeca?
Branched second dorsal fin rays usually 9; anal fin
branched rays 9; pectoral fin short, not reaching dorsal fin level; Caspian Sea
---> 3
3. Pyloric caeca equal in length; scales of head and back
with one groove; oral edge of preorbital moderately concave ---> Liza aurata
Pyloric caeca in two
groups, 3-5 short and 3-4 long; scales of head and back with 2-7 or more
grooves; oral edge of preorbital bone deeply notched = Liza saliens
Key to the species of Cyprinodontidae
?
1. Lateral line scales 36-47; Zagros Mountains west of
Esfahan = Aphanius vladykovi
Lateral line scales 24-35, mostly 31 or less ---> 2
2. Total dorsal fin rays ; total anal fin rays ; Genu Hot
spring near Bandar Abbas = Aphanius ginaonis
Total dorsal fin rays ; total anal fin rays ---> 3
3. Males* lemon-yellow with two broad bars on caudal fin;
females ?; coastal streams of the Persain Gulf and Sea of Oman, and the Hamun-e
Jaz Murian basin = Aphanius dispar
Males not lemon-yellow ?? ---> 4
4. Females* with flank stripes; males?; Lake Maharlu basin
near Shiraz = Aphanius persicus
Females with flank spots ---> 5
5. Females with lozenge-shaped spot at caudal fin base;
males? Kor River basin = Aphanius sophiae
Females ; males? = Aphanius mento
* Almost any sample will contain both males and females, clearly distinguished by colour and pigment patterns.
Key to the genera and species of Percidae
1. Canine teeth absent; prominent bars on flank; anal fin
branched rays usually 8-9, rarely 10; lateral line scales 77 or less = Perca
fluviatilis
Canine teeth present; no bars on flank; anal fin branched
rays rarely 10, usually 11 or more; lateral line scales 78 or more ---> 2
2. More than 18 branched rays in the dorsal fin; interorbital
width equal to or less than eye diameter = Sander lucioperca
Less than 19 branched
rays in the dorsal fin; interorbital width greater than eye diameter = Sander
marinum
Key to the Salmonidae
NEEDS to be checked
1. Teeth in lower jaw absent or weak and brush-like; scales
large, 13 or less from dorsal fin origin to lateral line, 100 or less in lateral
line CHECK; caudal fin clearly forked ---> 2
Teeth in lower jaw strong and conical; lower jaw long,
extending back to or past mid-eye; scales small, 19 or more from dorsal fin
origin to lateral line, 115 or more in the lateral line CHECK; caudal fin
truncate ---> 3
2. Mouth small? define; snout projects beyond lower jaw; ?,
lower jaw not projecting markedly beyond upper jaw CHECK; teeth in roof of mouth
few or absent; head length usually 4 times or more in standard length; body not
pike-like = Coregonus lavaretus
Mouth large?; snout not projecting; lower jaw obviously
projecting beyond upper jaw; teeth in roof of mouth in broad bands; head length
usually less than 4 times in standard length; body pike-like ?fusiform? =
Stenodus leucichthys
3. Major anal fin rays 12 or more; anterior edge of preoperculum meeting orbital bones; pyloric caeca 140-249; Caspian Sea =
Oncorhynchus keta
Major anal fin rays 13 or less; gap between anterior edge
of preoperculum and orbital bones; pyloric caeca 23-66 ---> 4
4. Body with dark spots on light background; vomer with
teeth on head and shaft; lower fins without white leading edge; Caspian Sea =
Salmo trutta
Body with light spots on dark background; vomer with
teeth on head only; lower fins with white leading edge; ? = Salvelinus
fontinalis
Key to the species of Siluridae
1. Teeth robust and long
(snaggly, catching on flesh); the upper and lower jaws meet at a dorsal and
superior position; distinctly and coarsely
serrate pectoral fin spine posteriorly; colour light; Tigris River basin =
Silurus triostegus
Teeth short and weak (not snaggly); upper and lower jaws meeting at an antero-dorsal position;
finely serrate or smooth pectoral spine posteriorly; colour dark; Caspian Sea,
Lake Orumiyeh and Tedzhen River basins=
Silurus glanis
Key to the species of Sisoridae
1. Head and body dorso-laterally without striated or elongate
tubercles; Tigris River, Gulf = Glyptothorax silviae
Head and body dorso-laterally with striated or elongate
tubercles; Tigris River ---> 2
2. Thoracic adhesive apparatus ("sucker") wider than long or
about equal; caudal peduncle short (5.9-6.0 in standard length) =
Glyptothorax kurdistanicus
Thoracic adhesive apparatus markedly longer than wide;
caudal peduncle long (4.0-5.3 in standard length) ---> 3
3. Pectoral fin extends to origin of pelvic fin (pectoral fin
length in standard length 3.8-4.1); head long (4.0-4.2 in standard length) =
Glyptothorax cous
Pectoral fin does not extend to origin of pelvic fin
(pectoral fin length in standard length 4.3-4.6); head short (4.3-4.5 in
standard length) = Glyptothorax armeniacus
© Brian W. Coad (www.briancoad.com)