Animals
The fastest sea creature:
Dolphin. Dolphins usually reach the speed of 27-37 km/h They, of course, are not champions. It is known that sail fish and sword fish reach speed of 80-100 km/h. But they are capable to keep this speed only for a short period of time. Therefore, the dolphin is considered the fastest sea creature.
The slowest sea creature: 
This is not a sea turtle, as many like to think. A common star fish. Its speed is not more than 50-60 cm/h.
The most dangerous to human sea creatures: 
Of course, the sharks. But no less frightening and dangerous fish is barracuda. This is sea pike of 1-2 meters in length, it is very fast, aggressive. Its fangs are sharp, as a knife.
Killer whales are more dangerous, than sharks and barracudas . But there is no details of killer whales attack on the man. Killer whales hunt in a flock, normally attacking walruses and seals. 
Its amazing, but the 7.5-meter creatures are able to attack even a whale!
Following sea creatures: moray, jelly fish, synanceia verrucosa, lion fish (often called zebra- fish)
are also dangerous to humans.
The smallest lizards: 
Australian short-tailed lizards. Their length is about 20-25 centimeters.
The smallest crocodile: 
Cuvier's dwarf caiman. Not longer than one and a half meters.
The largest land tortoise: 
Galápagos tortoise. Its body length - 1.5 meters. Weight - about three hundred pounds.
The biggest snake: 
Famous, everyone knows anaconda. It is 12 meters long, and weighing two hundred kilograms! Anaconda is incredibly strong snake. Its power can charm anyone. The ration of this creatures includes both crocodiles and turtles.
Most venomous snakes: 
King Cobra (it is considered the largest poisonous snake), rattle snake, African snake and Taipan.
The fastest venomous snake: 
Mamba. Its very hard to get away from her for man. Recorded mamba's speed is 11.3 km/h!
The largest frog: 
Goliath frog length of 25-30 cm, and its mass is 3.5 kilograms!
The smallest frog:
Cocoa - the smallest frog in the world. It is found in the rainforests of Colombia. Its length is 2.3 cm. A weight is just over one gram.
Most venomous frog: 
Spotted dart frogs are not only considered the most poisonous frog. It also carries the title of the most venomous creatures on the planet! This tiny creature is found in the jungles of South America and Colombia. One frog can kill a 1,5 thousand people! Moreover, the properties of the deadly poison remains 15 years.
The longest fish: 
Giant Oar fish. This is the fish of stunning beauty, it usually has a length from 9 up to 15 meters.
The longest invertebrate: 
Giant squid of Architeuthis species, having a length up to 17 meters.
The most dangerous parasites to humans: 
Guinea worm parasite, is able to reach a length of 2 meters. But in Russia and Ukraine this parasite is completely eradicated.
Cochin china worm. Distributed in the warm countries such as Italy. Is very prolific.
Filamentous worms of spiral trichina species and flatworms of Echinococcus species also are very dangerous.
The largest beetles in Russia:
This ussuri longhorn beetle, with length of 10 cm (without tendrils), with tendrils can reach 14 centimeters. This species is found in the Ussuri taiga in the Far East and Korea.
The largest and fastest centipede: 
Scolopendra gigantea has a length of 30 centimeters, is capable to kill a man with its bite. Scolopendra gigantea preys on small frogs and lizards. The fastest is Scutigera coleoptrata.
The most dangerous spiders: 
Karakurt has a size of less than ten centimeters in length, black color with red spots. Its bite is not always fatal.
Apulia tarantula causes feverish condition of man
, it length is less than 60 millimeters.
And the females malmignata spider also has poisonous eggs! The body of the spider is completely 
impregnated with poison.
Brazilian wandering spider are very dangerous, they secreting nerve paralytic poison.
South Russian tarantula is the most poisonous spider in Russia and 
Ukraine. Its length is 38 mm. Also tarantula is the largest spider in Russia.