Fish book son indd

Sturgeons – contemporaries of dinosaurs
137
River system, and false shovelnose sturgeons (Pseudoscaphirhynchus) occur 
in the basins of the Amu Darya and Syr Darya rivers. The Central Asian 
shovelnose sturgeons diff er from their American counterparts with their 
shorter caudal peduncle, which is not entirely covered with spikes, as well as 
with their underdeveloped air bladder (American shovelnose sturgeons have 
a well-developed air bladder).
Genus shovelnose sturgeon (
Scaphirhynchus
)
The common shovelnose sturgeon  (S. platorynchus) inhabits the 
Mississippi River and Missouri River systems. Its length is up to 90 cm. These 
sturgeons spawn in spring and summer and for this purpose they travel to 
tributaries with rocky bott oms. They mainly feed on water insect larvae. 
Common shovelnose sturgeons were commercially important in the past. 
However, their abundance has now dramatically decreased. 
Pallid sturgeon (Scaphirhynchus albus Forbes et Richardson, 1905) – 
Lower Missouri River basin.
Pallid sturgeon (
Scaphirhynchus albus
)

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G.M.Palatnikov,  R.U.Qasimov
138
This is a very rare and endangered species, included in the IUCN Red 
List, category I.
Pallid sturgeons reach a length of 1.5 m and weight of about 32 kg. Like 
other sturgeons, pallid sturgeons have fi ve rows of thick cartilage plates. They 
have a shovel-like snout and four barbels which descend from the snout in 
front of the mouth. The two inner barbels are approximately half as long as 
the outer ones. They do not have plates/scutes on their undersides.
Pallid sturgeons occur in the Mississippi and Missouri rivers within 
the states of Montana, Dakota, Kansas, Nebraska, Illinois, Arkansas and 
Missouri, as well as southward to Louisiana. They are considerably scarcer 
than the other shovelnose species which inhabits this area, S. platorynchus. 
Their biology remains poorly studied. These sturgeons live in fast-fl owing 
rivers near solid sand or gravel bott om. In populations the females dominate 
(by 2:1). They spawn between the months of June and August. The eggs are 
very small and are laid onto the bott om. The sturgeons feed on insect larvae 
and small fi sh and grow much faster than S. platorynchusi. Reasons of their 
low abundance are not known.
A number of US states (Missouri, Illinois, etc.) have banned the catch of 
this species. By way of control measures it is proposed to establish a size limit 
and hauling ban, at least for the spawning period.
Genus false shovelnose sturgeon (Pseudoscaphirhynchus)
Represented by three species, of which two - the large Amu-dar 
shovelnose (Pseudoscaphirhynchus kaufmanni) and small Amu-dar shovelnose 
sturgeon (Pseudoscaphirhynchus hermanni) - are found in the Amu Darya, and 
one - the Syr-darya shovelnose sturgeon (Pseudoscaphirhynchus fedtschenkoi) 
- in the Syr Darya. Two latt er species have always been very rare. Scientists 
have learned about them only recently - late last century. A.P. Fedchenko, 
the eminent Russian geographer and traveler, discovered the Syr-darya 
shovelnose sturgeon in 1871; the large Amu-dar shovelnose was found in 
1874 by the famous natural scientist M.N. Bodganov; and Academician I.A. 
Severtsov, a zoogeographer, discovered the small Amu-darya shovelnose 
sturgeon in 1876.

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Sturgeons – contemporaries of dinosaurs
139
The false shovelnose sturgeons inhabit the plain stretches of these rivers, 
from the seashore to the piedmont regions. They do not enter the salty water 
of the Sea of Aral. The Central Asian shovelnose sturgeons are not very large. 
The largest of them, the large Amu-dar shovelnose, reaches 58 cm in length 
and 760 g in weight (as an exception, specimens weighing up to 2 kg have 
been encountered in the past.) The small shovelnose sturgeons are much 
smaller, up to 27 cm; their Syr Darya counterparts are of the same size.
The false shovelnose sturgeons are typical river channel dwellers. They 
prefer to stay on sand and gravel shallows and in distributaries. To prevent 
being carried away by the stream, the small and Syr-darya shovelnose 
sturgeons have, apart from their wide and fl at snout, the unique creasy 
shape of their pectoral fi ns, which act as a surculus. The large Amu-darya 
shovelnose sturgeons (and some specimens of Syr-darya sturgeons) have the 
upper blade of tail fi n stretched into a long thread that apparently performs 
the function of a stabilizer. 
Head of Shovelnose Sturgeon
The large shovelnose sturgeons also have 1 to 9 spikes on the tip of their 
snouts, which probably play an important role in spawning in a fast stream. 
The shovelnose sturgeons spawn on coarse-grain sand shallows and over 

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G.M.Palatnikov,  R.U.Qasimov
140
scatt ered rocks in the river mouth in shallow water (1.5-2m.) Spawning takes 
place in early spring between March and April when the water temperature 
is 10-14
0
C. The female shovelnose sturgeon may lay up to 15,000 eggs, but 
usually lays within 2,000; the Syr-darya shovelnose sturgeons lay up to 
1,500 eggs; the fertility rate of the small shovelnose sturgeon is unknown. 
These sturgeons reach sexual maturity at the age of 6-7 years; males usually 
reach maturity a year before females. Apart from the regular form, the large 
shovelnose sturgeon also has a stunted dwarf form that reaches maturity 
at a length of 23-24cm and weight of only 39-40g. The favorite food for 
shovelnose sturgeons are small bott om-dwelling invertebrates (larvae of 
chironomids, trichopterans, mayfl ies)  and  fi sh roe. The large shovelnose 
sturgeons also feed on larger prey (the young of barb, razorfi sh, loach and 
ostroluchka (Capoetabrama kuschakewitsch.)
Large Amu-dar shovelnose sturgeon  (Pseudoscaphirhynchus kaufmanni 
Bogdanov, 1874) - inhabits the Amu Darya River.
Common name: hackleback, small beluga (Russian); tash-bekre, donguz-
balik (Uzbek).
This is a rare and endemic endangered species (category I), which is 
included in the Red List.
The largest of the central Asian shovelnose sturgeons att ains a length of 
58 cm (without the tail thread) and a weight of 760 g; individual specimens 
weighing up to 2 kg have been encountered in the past. This sturgeon has a 
very wide shovel-shaped snout. There are between 1 and 9 spikes on the tip 
of the snout. The upper blade of the tail fi n stretches into a long thread that 
performs the function of a stabilizer. Just like other shovelnose sturgeons, large 
shovelnose sturgeons have very small eyes, oft en almost entirely covered with 
skin. The bony scutes on the body are very big and form a distinctive mail 
that protects the fi sh from mechanical damage. There are 9-15 scutes in the 
back row, 28-40 on the side, and 5-11 on the underside. The coloration varies 
signifi cantly from dark-brown to black and gray. The underside is gray-white.
In the past these sturgeons were encountered in the entire lowland 
part of the Amu Darya from the Panj River to the seashore, as well as in the 
lower Vakhsh, Kafi rnigan, Surkhandarya and Kyzylsu. Today, following the 
regulation of the Amu Darya and a number of its tributaries. it is preserved 
in small numbers only upstream of Chardzhou. 
For a long time the indigenous people along the Amu Darya restrained 
from eating large shovelnose sturgeons due to their long ‘tail’ resembling that 

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