The cephalothorax, also called prosoma in some groups, is a tagma of various arthropods, comprising the head and the thorax fused together, as distinct from the abdomen behind. (The terms prosoma and opisthosoma are equivalent to cephalothorax and abdomen in some groups.)
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What is a cephalothorax?

Definition of cephalothorax : the united head and thorax of an arachnid or higher crustacean.

What is the cephalothorax of crustaceans?

Region of the body in decapod crustaceans that is covered by the carapace, with the boundary between head and thorax indicated by the cervical groove. In lobsters the cephalothorax is called the “body;” in shrimps it is called “head.”. [

What is a cephalothorax abdomen?

The cephalothorax or prosoma is the anterior most of the two body parts of arachnids (the other part being the abdomen or opisthosoma). The cephalothorax features the eyes, mouth and legs of the arachnid. The cephalothorax is more rigid than the abdomen and contains the muscles used to operate the limbs.

What appendages are attached to the cephalothorax?

Cephalothorax. The cephalothorax, also called prosoma, is composed of two primary surfaces: a dorsal carapace and a ventral sternum. Most external appendages on the spider are attached to the cephalothorax, including the eyes, chelicerae and other mouthparts, pedipalps and legs.

What animals have a cephalothorax?

Cephalothorax: The Animal Files. In some arthropods, the Cephalothorax is a section of the body that combines the head and the thorax. Arachnids and crustaceans have a Cephalothorax.

Is cephalothorax found in earthworms?

Cephalothorax is present in arachnids. Option C is not correct. Option D Metathorax: Metathorax is the segment that bears the hindwings in most winged insects, though sometimes these may be reduced or modified as in flies, the metathorax is usually present in insects not in earthworm.

Which type of arthropod has a cephalothorax?

Arachnids. Arachnids are a group of arthropods that include spiders and ticks. They have two body parts: the cephalothorax (head-middle) and the abdomen.

What is the cephalothorax of a crayfish?

The cephalothorax consists of the cephalic (or head) region and the thoracic region. The part of the exoskeleton that covers the cephalothorax is called the carapace. The abdomen is located behind the cephalothorax and consists of six clearly divided segments. The cephalothorax consists of 3 segments.

What is a cephalothorax and in which arthropod class is it found?

cephalothorax In some members of the phylum Arthropoda, the fused head and thorax. It is found in members of the Chelicerata (classes Merostomata, Arachnida, and Pycnogonida), and in most Crustacea.

What is the difference between cephalothorax and abdomen?

What is the difference between Cephalothorax and Abdomen? Cephalothorax is present only in arthropods while abdomen is common among most of other animal phyla. The cuticle is harder in cephalothorax than in abdomen. Therefore, the abdomen is flexible and tender while the cephalothorax in rigid and strong.

Is prawn a cephalothorax?

The body of the prawn is divisible into Cephalothorax and abdomen. Cephalothorax is made by 13 segments which includes cephalic and thoracic regions. The cephalic region contains 5 segments and thoracic region contains 8 segments.

Is cephalothorax found in prawn?

Cephalothorax: Cephalothorax is the broad, un-segmented and cylindrical anterior part. It is formed by the fusion of head and thorax. In fact, during the development of prawn, one pre-segmental region and first fourteen segments fuse to form cephalothorax.

Where is the cephalothorax on a spider?

The cephalothorax is the first of 2 body parts on a spider. It is a combination of the head and thorax, and on it are found the legs, eyes, pedipalps, chelicerae, and other mouthparts.

Do all arthropods have cephalothorax?

Most arthropod’s bodies have three sections – the head, the thorax, and the abdomen. The thorax is the part of the body between the head and the abdomen. In some species of arthropods, the head and the thorax are one section called the cephalothorax. … Most arthropods that live in the water have gills.

What are the characteristics of Arachnida?

  • Four pairs of legs (eight total). …
  • Arachnids also have two additional pairs of appendages. …
  • Arachnids do not have antennae or wings.
  • The arachnid body is organized into the cephalothorax, a fusion of the head and thorax, and the abdomen.
Are butterflies Hexapods?

Hexapods are characterized by the presence of a head, thorax, and abdomen, constituting three tagma. … Many of the common insects we encounter on a daily basis, including ants, cockroaches, butterflies, and flies, are examples of Hexapoda.

What are the Tagmata sections of an insect?

Insects first evolved 300 million years ago. Their body is divided into three tagmata: head, thorax, abdomen.

Is cephalothorax found in cockroach?

Answers. Head thorax abdomen is seen in cockroach( just refer ncert)……. Cephalothorax is seen in crustaceans…..

Do insects have a cephalothorax?

The word cephalothorax is derived from the Greek words for head ( κεφαλή , kephalé ) and thorax ( θώραξ , thórax ). This fusion of the head and thorax is seen in chelicerates and crustaceans; in other groups, such as the Hexapoda (including insects), the head remains free of the thorax.

Do crabs have cephalothorax?

crab, crustacean with an enlarged cephalothorax covered by a broad, flat shell called the carapace. … Although they are capable of locomotion in all directions, crabs tend to move sideways; swimming crabs have the last pair of legs flattened to form paddles.

Is Prawn an arthropod?

Crustaceans (Crustacea /krʌˈsteɪʃə/) form a large, diverse arthropod taxon which includes such animals as crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, barnacles, copepods, amphipods and mantis shrimp. … Like other arthropods, crustaceans have an exoskeleton, which they moult to grow.

Do ticks have a cephalothorax?

All adult ticks have four pairs of legs, no antennae and two fused body parts (head and cephalothorax).

What are the three orders of Arachnida?

There are 15 extant orders of arachnids: Scorpiones (true scorpions), Palpigradi (palpigrades), Solifugida (sun spiders), Uropygi (whipscorpions), Amblypygi (whipspiders), Schizomida (micro-whipscorpions), Araneae (true spiders), Pseudoscorpiones (pseudoscorpions), Ricinulei (ricinuleids), Opiliones (harvestmen), and …

What's the function of maxillipeds in crayfish?

The second pair of maxillae also helps to draw water over the gills. Of the eight pairs of appendages on the cephalothorax, the first three are maxillipeds, which hold food during eating. The chelipeds are the large claws that the crayfish uses for defense and to capture prey.

How many maxillipeds Do crayfish have?

Below the rostrum are two pairs of mandibles (the jaws) and three pairs of maxillipeds, which are small appendages that direct food to the mouth.

Are Swimmerets jointed?

The image shows a female crayfish; in males the first set of swimmerets are enlarged for grasping the female during copulation. … This claw is called the CHELIPED, it is also jointed and the crayfish uses it to capture food and for defense.

What are Biramous appendages?

biramous appendage A type of appendage that is characteristic of arthropods of the phylum Crustacea. It forks from the basal protopodite to form two branches, the inner endopodite and the outer exopodite (see illustration). Each of these branches can be composed of either one or more segments.

Which two classifications contain animals that have both a cephalothorax and an abdomen?

The Class arachnida is a large and diverse group. All arachnids belong to a subphylum (a division of Arthropoda) known as the Chelicerata, of which there are approximately 65,000 described species (~8,000 in North America). They are characterized by having two body regions, a cephalothorax and an abdomen.

What characteristics do all species of the phylum Arthropoda share?

  • Exoskeletons made of chitin.
  • Highly developed sense organs.
  • Jointed limbs (the limbs must be jointed like the joints in a suit of armor, since the exoskeleton is rigid and cannot bend to allow movement)
  • Segmented bodies.
  • Ventral nervous system. …
  • Bilateral symmetry.
Why are the Maxillipeds related to eating?

Two pairs of maxillae hold solid food, tear it, and pass it to the mouth. The second pair of maxillae also helps to draw water over the gills. Of the eight pairs of appendages on the cephalothorax, the first three are maxillipeds, which hold food during eating.

What makes up a crayfish body?

Crayfish have two body segments, the cephalothorax, which is the fused head and thorax, and the abdomen. The cephalothorax is protected by a carapace and is where you’ll find the eyes, antennae, and antennules. … Past the head region, internally the cephalothorax contains major organs like the heart, liver, and gills.

Why is the heart of a shrimp in its head?

Actually the heart of shrimp is located on its thorax reason just after the head but it seems as situated in its head because the head & thorax is totally covered with a single exoskeleton only. This is because the shrimp’s thorax can be mistaken as still part of the shrimps head.

Why is prawn and Grasshopper in different classes?

Crustaceans have two pairs of antennae, while insects have one pair of these structures. Crustaceans use gills while insects use the tracheal system for respiration. As a result, these structural and ecological characteristics are used for the separation of prawns and grasshopper into different classes of Arthropoda.

What are the appendages found at the cephalothorax of the shrimp?

The thoracic appendages of cephalothorax are modified to function as mouthparts and are called maxillipeds. The five remaining ‘free’ thoracic segments bear the walking legs, or pereopods. The first pereopod (1st walking leg) bears a pincer, or chela, and is called the cheliped. In shrimps the chela is small and weak.

Do roaches have noses?

Roaches’ heads house their eyes, antennae and mouthparts. … The other is that roaches don’t breathe through a nose or mouth. Instead, they draw air through spiracles, or holes in their sides.

What are insect appendages?

In invertebrate biology, an appendage refers to any of the homologous body parts that may extend from a body segment, including antennae, mouthparts (including mandibles, maxillae and maxillipeds), gills, locomotor legs (pereiopods for walking, and pleopods for swimming), sexual organs (gonopods), and parts of the tail …

What makes myriapoda different from other arthropods?

They are distinguished by the fusion of each pair of body segments into a single unit, giving the appearance of having two pairs of legs per segment. Around 12,000 species have been described, which may represent less than a tenth of the true global millipede diversity.

Do all spiders have spinnerets?

Most spiders have six spinnerets and four to six glands for producing silk, although these numbers vary by species, according to the Illinois Department of Natural Resources. All spiders can produce silk, but not all spider silk is the same.

Why do spiders freeze when you see them?

The principals are responsible for detecting shape, and secondaries for detecting movement. When they see something moving, the spider body freezes, but if you were to measure muscle activity, you’d notice that the secondary eye muscles are constantly working (this happens even if you cover the principal eyes).

Do spiders have fangs or pincers?

Commonly referred to as “jaws”, chelicerae may be shaped as either articulated fangs, or similarly to pincers. Some chelicerae, such as those found on nearly all spiders, are hollow and contain (or are connected to) venom glands, and are used to inject venom into prey or a perceived threat.