Echidna, (family Tachyglossidae), also called spiny anteater, any of four species of peculiar egg-laying mammals from Australia, Tasmania, and New Guinea that eat and breathe through a bald tubular beak protruding from a dome-shaped body covered in spines. Source: SmithsonianMag.com Step 2 : Answer to the question "Which animal has a skull but no spine?" The most popular animal that starts with the letter S is the sloth, a slow-moving creature believed to be distantly related to anteaters and armadillos. Read below for information on 75 different animals that start with the letter S, from the extinct sabre-toothed tiger to swans. This word comes from the word that we use for the bones that make up the backbone. The short-beaked echidna has dark fur almost completely hidden by a covering of hollow, barbless quills, called spines, on its back and sides. The beige-and-black spines on all four species, which are about 2 inches (5 centimeters) long, help camouflage the echidna in the brush. The snout on this animal is long and tubular which helps them smell their prey and eat it, too. Spines are also found in internal organs in invertebrates, such as the copulatory spines in the male or female organs of certain flatworms. Hagfish: Some examples of … They are generally considered quite ugly, but they are well adapted for survival. Their bodies are brownish black and covered with spines and coarse hair. The hagfish's skull consists of cartilage rather than bone. These echidnas are sometimes called spiny anteaters. The backbone (or spinal column) is made up of bones known as the vertebrae and hence the animals that have a backbone are called vertebrates. Passive and shy, these somewhat slow-moving creatures will roll up in a ball for protection. Sea urchin, any of about 950 living species of spiny marine invertebrate animals (class Echinoidea, phylum Echinodermata) with a globular body and a radial arrangement of organs, shown by five bands of pores running from mouth to anus over the test (internal skeleton). Mammals are vertebrates, which means that they all have backbones (spines). The animals that have backbones are called vertebrates. Believe it or not, most animals don't have backbones -- mammals are one of the few groups that do. In plant morphology, thorns, spines, and prickles, and in general spinose structures (sometimes called spinose teeth or spinose apical processes), are hard, rigid extensions or modifications of leaves, roots, stems or buds with sharp, stiff ends, and generally serve the same function: physically deterring animals from eating the plant material. The arms of the echidna are very strong with claws that are designed to dig. This includes giraffes who have VERY long spines! Spines are also found in invertebrate animals, such as sea urchins.They are a feature of the shell of a number of different species of gastropod and bivalve mollusks, including the venus clam Pitar lupanaria. The hagfish is the only animal to have a skull but no vertebrae making a spine. The pores accommodate tube feet, which are slender, extensible, and often sucker-tipped. The great white shark (Carcharodon carcharias) is first on our list of animals with scales and fins.The great white shark is one of the most popular shark species in the world, thanks in part to the famous movie ‘Jaws.’ This shark is characterized by its large size and powerful jaw which contain two rows of serrated and sharp teeth. All mammals, except some sea cows and sloths have seven bones in their necks. Echidnas have beady eyes and mere slits for ears, and at the end of their beaks are two small nostrils and a tiny mouth. Long-beaked echidnas have little fur and more visible spines. The echidnas stout spines extend passed the length of their coarse fur and serve as their only line of defense against the myriad of animals that consider eating them.