Green Iguana Society logo  1999-2001, D. Baze

Acclimate - To get used to something, to feel comfortable about, to become accustomed to.

Arboreal - Living in trees. Wild iguanas are arboreal, and spend most of their time in the trees, feeding on leaves.

Alligator Roll - This is a type of behavior that is seen when an iguana is being held by hands or leash and desperately wants to be let go. It is beyond squirming - it is a full-body, sideways, somersault-type roll, similar to what alligators and crocodiles do when they role underwater to tear their prey into pieces. For this reason, it is also referred to as a crocodile roll.

Aloe Vera - A gel-like substance produced in the stems of aloe vera plants. It can be purchased at most stores and pharmacies. Aloe vera is often used as a lubricant to help remove shedding skin.

Analgesic - A drug that relieves pain. They are available in three forms: injectable, oral and topical.

ARAV - Abbreviation for the Association of Reptile and Amphibian Veterinarians. Membership in this organization is something to look for when screening vets for your iguana. For more information, please visit ARAV's website at

Bask - To lay in the sun to absorb heat and UV rays. Basking is an important part of an iguana's daily life, and makes up most of their day.

Betadine - An iodine solution used to clean wounds. For more information on Betadine and its uses, visit the Betadine page in the First Aid Kit section.

Brewer's Yeast - A dietary supplement that consists of inactivated yeast cells that are rich in thiamin (vitamin B1). Brewer's yeast is often added to food that has been frozen and then thawed, since the freezing process tends to destroy much of the thiamin present in foods. Brewer's yeast supplement is available at health food stores, and should not be confused with active brewer's yeast that is used in the making of alcoholic beverages. For more information on storing and freezing food, see the Food and Feeding page.

Bug Eyes - A term used by iguana owners to describe a behavior during which the eyes are closed and "bugged out" or puffed up. Iguanas often do this when they have itchy eyes - if they are shedding on their face, for example. Some iguanas will do this when their eyebrow ridges are rubbed. This seems to be a sign that they are enjoying their eye rub. This behavior is also referred to as frog eyes.

Ca:P - A short-hand notation for Calcium/Phosphorus ratio. Iguanas need a diet that contains twice as much calcium (see below) as it does phosphorus (see below), which is often noted as 2:1 Ca:P. For more information on iguana diets and the importance of the calcium and phosphorus amounts, see the Food and Feeding page.

Calcium - A mineral found in leafy green vegetables and in other foods, to a lesser extent. Calcium is used by the body to build strong bones, and it plays an important role in the proper functioning of the nervous system. Iguanas need calcium in fairly high amounts to be healthy. Calcium deficiency is one of the most common causes of MBD (see below). For more information about calcium in the diet, see the Food and Feeding page.

CHE - Short-hand for Ceramic Heat Emitter. CHEs screw into most ordinary light bulb sockets and come in various wattages. They give off heat, but no light. They are a great way to provide night-time heat when light is undesirable. Note: CHEs must be used with ceramic-socket fixtures to prevent fire hazards.

Cloaca - See Vent(below).

Cold-Blooded - See Ectothermic

Crocodile Roll - See Alligator Roll (above).

Cruciferous - A term referring to vegetables in the cabbage family such as broccoli, cabbage and kale. Cruciferous vegetables contain goitrogens (see below), which interfere with the way the body absorbs iodine. Feeding too many cruciferous vegetables to iguanas can cause goiter (see below). For more information on diet, refer to the Food and Feeding page.

Dehydration - The condition in which the body does not have the proper amount of water. Dehydration is a very common condition for iguanas, because they require high amounts of water and humidity (being from the tropical forest) and tend not to drink water directly. Chronic dehydration can lead to kidney damage, so owners should be aware of the symptoms, treatments and prevention of dehydration. For more information on dehydration, see the Miscellaneous Conditions page.

Dewlap - The flap of skin that lies under the chin. The dewlap can be extended during display and is an important component of iguana body language. For more information about iguana communication, see the Body Language page.

Digits - Another term for toes, or fingers.

Disinfect - Any treatment of a non-living object which kills or inhibits the growth of microorganisms (mainly bacteria). The cleaning substance used is called a disinfectant. To disinfect is not the same as to sterilize, which is the actual destruction of all microorganisms, including resistant spores and capsules. For more information on disinfecting iguana habitats, etc., see the Cleaning and Cleanliness page.

Dystocia - Another term for Egg-Binding (see below).

Ectothermic - Not able to heat the body from within. Iguanas and other reptiles are ectothermic, and therefore need to be provided with an outside heat source so they can regulate their body temperature. Also referred to as cold-blooded.

Egg-Bound - Refers to a female iguana suffering from what is known as egg-binding - a serious condition that results when eggs are retained within the body and cannot be laid. Egg-binding can be the result of many different factors, but egg-bound females need to see a qualified veterinarian immediately. For more information on egg-laying, see the Breeding Season Issues page.

Enclosure - Another term for a cage, or habitat. For information about enclosures, see the Habitat page.

Evil-eye - A term often used by iguana owners to describe an intense, angry look given to them by a displeased iguana. The evil-eye often preceeds nsuch behaviors as biting or tail-whipping.

Femoral Pores - Pores that run in a line along the inner thigh on the hind legs of both male and female iguanas. In males, these pores are large, easily visible, and often filled with a waxy substance. In females, the pores are small and inconspicuous. For photos and more information on femoral pores, visit our Sexing Iguanas and Anatomy pages.

Fibrous Osteodystrophy - Another term for Metabolic Bone Disease (see below).

Fluorescent bulbs - Refers to long, tubular light bulbs that contain a substance on the inside of the tube called phosphor, which gives of visible light in the presence of ultraviolet light. Fluorescent bulbs are the only type of bulb that give off ultraviolet light (see below), which iguanas require. Slang: tube lights

Free Roaming - Allowing an iguana to exist uncaged in a room, part of a house, or a whole house. Free roaming has advantages and disadvantages when compared to keeping an iguana in an enclosure. For more information, see the Freedom and Free Roaming pages.

Frog Eyes - See Bug Eyes (above).

Full Spectrum - A term that is used to describe a type of fluorescent light bulb which gives off light from all or most parts of the light spectrum, and which is most similar to real sunlight.

Gaping - When an iguana opens its mouth and holds it open. This is often a behavior seen during aggressive displays. It is a threat/warning that biting may be imminent. For more information on displays, visit the Body Language page.

Glycerin - A substance used as a lubricant. For more information, see the First Aid kit page.

Goiter - Swelling of the thyroid gland. Goiter may be caused by many things, but in iguanas it is often caused by improper diet, such as one that contains too many cruciferous vegetables (see above). Goiter can also exhibit others symptoms such as bulging eyes and an abnormally high metabolic rate. For more information on goiter, refer to the Other Diseases page.

Goitrogens - Chemical compounds which interfere with the body's ability to absorb and utilize iodine. If too many cruciferous vegetables (see above) are included in the diet, goiter (see above) may result.

Gout - A disease characterized by swollen, painful joints in the feet. In iguanas, poor diet, especially too much protein in the diet, is usually the cause. For more information on proper diet and gout, visit the Food and Feeding page and the Other Diseases page, respectively.

Gravid - A term that refers to a female iguana that is carrying either infertile or fertile eggs. For signs of gravidity and information on egg-laying, see the Breeding Season Issues page.

Gravidity - The condition of being gravid (see above).

Habitat - See enclosure (above).

Hardware Cloth - A type of wire screening that is useful in making iguana enclosures. Hardware cloth is stronger than ordinary window screening. It is also referred to as hail screen. For more information, see the Habitat page.

Hatchet Mode - A term used by iguana owners to describe a posture that results when an iguana flattens its body from side to side, puffs out its dewlap (see above) and prepares to tail whip, bite or lunge. See the Body Language page for more information on posturing.

Head Bob - One of the main form of communication that iguanas use. Head bobs can be slow and large, fast and small, somewhere in-between, or a combination thereof. Head bobs can mean a variety of things, depending upon the iguana's mood at the time and the situation it is in. Head bobs can be combined with a side-to-side motion, which is also known as a shudder-bob (see below). For more information on bobbing, see the
Body Language page.

Heliothermic - Absorbing heat and energy from the sun. This term is sometimes used in place of ectothermic, or cold-blooded (see above).

Hemipenes (singular = hemipenis) - A male iguana's copulatory organs. Males do not have a single penis, but rather two hemipenes, that deliver sperm to the female's body during copulation. Hemipenes are often seen protruding from the vent (see below) during or after mating or other sexual activity. Hemipenes may also be visible during defecation, and may occasionally remain outside the body in what is known as a prolapse (see below). To see a photo of hemipenes, visit our Breeding Season Issues or Anatomy pages.

Herbivore - An animal that is a vegetarian, i.e. one that eats only plant matter. Iguanas are herbivores. For more information on diet, see the Food and Feeding page

Herp - An abbreviation for Herpetile (see below).

Herp Vet - A veterinarian that is knowledgeable of or that specializes in the care of herpetiles (reptiles and amphibians). It is important to be sure that your iguana sees a qualified herp vet on a regular basis.

Herpetile - A term that refers to reptiles and amphibians. Often abbreviated as "herps".

Herpetoculturist - A person who owns and/or breeds herpetiles (see above).

Herpetologist - A person who studies and/or has a degree in the study of reptiles and amphibians.

Herpetology - The study of reptiles and amphibians.

Hindgut - The section of an iguana's intestine that lies between the small and large intestines. The hindgut houses populations of helpful gut bacteria which break down the hard-to-digest cellulose that is a component of all plant foods.

Humidifier - An appliance that emits water vapor into the air, and thus raises the humidity (see below) of the environment.

Humidity - A measure of the amount of water in the air. Iguanas require high humidity environments to remain healthy and avoid dehydration (see above). For suggestions on raising the humidity of an iguana's environment, see the Habitat page.

Husbandry - A term that refers to the care of something. This term encompasses all aspects of iguana care, from diet, housing, heating, cleaning, etc. Upon bringing your iguana in for a check-up, one of the first things a veterinarian will ask you to do is to describe your husbandry.

Hygiene - Refers to the cleanliness of something. For information on the importance of proper hygiene in iguana care, see the Cleaning and Cleanliness page.

Hypothyroidism - A medical condition that occurs when the thyroid gland does not produce enough of the metabolism-regulating hormones that are required for proper metabolism levels. In iguanas, this is most often caused by the feeding of too many cruciferous plants (see above), which contain goiterogens which interfere with normal thyroid function. Symptoms of hypothyroidism are decreased appetite, decreased growth while maintaining a "chubby" look, and lethargy, or decreased activity levels.

Hysterectomy - A surgical procedure performed on female iguanas that removes the ovaries and sometimes the oviducts and uterus as well. Also referred to as spay. To find out more about this procedure, visit the Breeding Season Issues page.

Iglet - A slang term for a baby or juvenile iguana.

Impaction - Refers to something blocking the intestine. Iguanas suffering from impaction are sometimes said to be impacted. Signs of impaction include inability to defecate and/or straining to do so. This potentially deadly condition needs immediate veterinary treatment. For more information, see the Miscellaneous Conditions page.

Incandescent bulbs - Ordinary, socket-type light bulbs that are used as a heat and light source. Incandescent bulbs do not give off UV light (see below).

Infrared bulbs - Light bulbs that give off visible light as well as infrared wavelengths, i.e. wavelengths of light that are slightly longer than visible light waves. Infrared bulbs are designed to give off large quantities of heat, and are often used to heat enclosures.

InterNet Mesh™ - A type of flexible netting that can be used in the construction of iguana enclosures. For more information, see the Habitat page.

Intramuscular (IM) - A term used to describe injections that are given into the muscle. This is a term that a vet might use when giving instructions to an iguana owner about certain treatments.

Intravenous (IV) - A term used to describe injections that are given directly into a vein. This term may be used by a veterinarian to describe treatment for certain disorders.

Jacobson's Organ - Also called the vomeronasal organ. The Jacobson's organ is a sensory organ located in the roof of the mouth which analyzes scent molecules collected from environmental objects. Iguanas toungue-flick objects to pick up these molecules, which are then transfered to the Jacobson's organ when the tongue brushes against it. The Jacobson's organ probably picks up a combination of scent and taste information from the environment.

Jowl - The skin and muscle under the lower jawbone. Both males and females have jowls, but in males the muscle is greatly enlarged, giving the jowls a puffy appearance. See the Anatomy page and the Sexing Iguanas page for photos.

Kwik-Stop - A commonly used brand of styptic powder (see below).

KY Jelly - A lubricant used to loosen stuck shed. KY Jelly can be purchased at most drug stores and pharmacies. For more information on lubricants, visit the First Aid Kit page.

Lethargy - Having a low activity level; not responding to surroundings or stimuli. Lethargy is most often a sign of serious illness and should not be ignored or mistaken for "tameness".

Love Toy - An object presented to a male iguana during his breeding season that will provide him with an outlet for his sexual urges and aggressions. A love toy may be almost anything - a stuffed animal, an old towel or sweatshirt - whatever the male will accept. For more information on love toys and why they may be beneficial, see the Breeding Season Issues page.

MBD - Abbreviation for Metabolic Bone Disease (see below).

Metabolic Bone Disease - Also referred to as MBD, this disease is the most common ailment in captive iguanas. It most often results from either poor diet, improper temperatures, lack of exposure to UV light (see below) or a combination thereof. Symptoms include soft, weak bones, swollen, rubbery jaw and twisted spines and limbs, among others. For more information, see the Metabolic Bone Disease page.

Mineral Oil - A substance used to loosen stuck shed and to treat constipation. For more information, see the First Aid Kit page.

Mites - Tiny external parasites (see below) that can sometimes infest iguanas and their habitats. Mites are arachnids - related to spiders - and suck blood from their hosts. An iguana with mites must be aggressively treated. For more information on mites, see the Parasites page.

Mouth Rot - Also referred to as stomatitis or ulcerative stomatitis, mouth rot is a secondary infection whose syptoms include yellow or yellow-white, cheesy-looking saliva and mouth sores. Mouth rot is indicative of another infection elsewhere in the body, and iguanas exhibiting signs of mouth rot need immediate veterinary care. For more information on mouth rot, see the Other Diseases page.

Necropsy - The term for an animal autopsy. Necropsies are often performed by veterinarians after an iguana's death to help determine the exact cause of death. Although many owners do not like the idea of having a necropsy performed on their iguana, such investigations help owners and veterinarians impove their understanding of iguana physiology and the proper way to care for them. For more information about the importance of necropsies, visit the Dealing with Death page.

Neuter - Surgery performed on male iguanas to remove the testes. Neutering of males is not commonly done because the surgery itself is difficult. Also, removal of the testes has not been shown to lessen breeding-season aggression. For more information on breeding season aggression and neutering in males, see the Breeding Season Issues page.

Nolvasan - A commonly used brand of chlorhexidine diacetate disinfectant. Nolvasan can be used to clean and disinfect iguana habitat accessories, and can be used to cleanse wounds. For more information, see the First Aid Kit page.

Nose Rub - A term used to describe both a common wound obtained when an iguana rubs its nose against an object, and the behavior itself. Iguanas often nose rub when they want to get out of their enclosures. They will rub their nose on the side of an aquarium, the door of an enclosure, or even the door of a room in a home, if they wish to get out of the area. Chronic nose rubbing is often a sign of stress, and may indicate that the enclosure is too small. For more information on nose rubs and how to treat the wounds, see the Miscellaneous Conditions page.

Nuchal Crest - The very top part of the neck, directly behind the head. See the Anatomy page for a photo.

Oxalates - Chemicals that occur naturally in some plants, such as spinach and chard, which bind to calcium and make it unusable to the body. Foods high in oxalates should make up only a small portion of an iguana's diet. For more information on diet, see the Food and Feeding page.

Parasites - Organisms that survive by living on or in the body of a host organism. Parasites generally do not kill their hosts, but they often contribute to overall ill health. Iguanas can be host to many internal (i.e. living in the body) parasites such as tapeworms, hookworms and protozoans, as well as external (i.e. living on the body) parasites such as ticks and mites. For more information on iguana parasites and how to treat them, see the Parasites page.

Parietal Eye - A tiny, transparent scale on the top of the head that detects light and dark. Iguanas use the parietal eye to alert them to aerial predators. Is sometimes referred to as the third-eye. To view a photo of the parietal eye, please visit our Anatomy page.

Particulate - Consisting of particles, often of a small size. This term is used most often in reference to enclosure substrates. Iguanas have the propensity to ingest particulate substrates such as wood chips. Since these substances can get stuck in the gut, causing impaction (see above), they should be avoided.

Per Os (PO) - A latin term that means "to give orally". Medication directions often use "PO" to indicate that the medicine should be given by mouth.

Phosphorus - A mineral that is a component of foods. In the body, calcium (see above) and phosphorus are at a balance. Too much phosphorus in the body can lower the amount of calcium and can lead to loss of calcium from the skeleton. Iguanas need a diet that contains twice as much calcium as it does phosphorus. For more details, see the Food and Feeding page.

Phytates - Chemicals that occur naturally in some plants, and which bind to calcium and make it unusable to the body. Foods high in phytates should make up only a small portion of an iguana's diet. For more information on diet, see the Food and Feeding page.

Plexiglas - A lightweight, clear material that may be used in the construction of iguana cages. Plexiglas has many advantages over glass and other building materials. For more information, see the Habitat page.

Posturing - A term used to describe an iguana that is displaying, often in an aggressive way. For photos and more information, see the Body Language page.

Prolapse - When an organ that is usually held inside the body protrudes and stays outside the body. In iguanas, intestinal and hemipenal (see hemipenes, above) prolapses can occur. Prolapses of any kind need immediate veterinary treatment. For more information, see the Miscellaneous Conditions page.

Protein - Molecules made from units called amino acids. Proteins are found in plant foods in small amounts. Proteins are an essential component of a healthy diet, and are used to build muscle and other body structures such as scales and claws, and act as enzymes in the body, which regulate the various chemical reactions needed for life. Although proteins are necessary, iguanas cannot handle the large amounts of proteins found in animal products such as meats, eggs and dairy products. A diet too high in protein can lead to gout (see above), and a diet too low in protein or missing certain proteins can also lead to ill-health. For more information on diet, see the Food and Feeding page.

Protozoans - Single-celled organisms that can be internal parasites (see above) in iguanas. There are a variety of protozoans that may be parasitic in iguanas. For more information, see the Parasites page.

Renal - A term that refers to the kidneys. One of the most common illnesses in captive iguanas is renal disease or failure.

Rut - A slang term for breeding season. For more information, see the Breeding Season Issues page.

Quick - The nerves and blood vessels that run down the center of the claw, or toenail. While trimming an iguana's nails, it is important not to cut them too short, lest you cut into the quick and cause bleeding and pain. For more information, see the Claw Trimming page.

Saline - A salt water solution. Saline solution is often used to flush wounds and eyes during cleaning. Contact lens solution is commonly used. For more information on saline, see the First Aid Kit page.

Salmonella - A type of bacteria that may be carried by some iguanas. Salmonella bacteria cause a condition known as salmonellosis in humans, which causes symptoms such as fever, nausea, and diarrhea. For more information on Salmonella bacteria and salmonellosis, see the Salmonella page.

Salt Expulsion - The process of ridding the body of salt by "snorting" it out the nostrils. Iguanas do not sweat, but they do have a gland, called the rhinal salt gland, near their nose which removes salts from the body and secretes them into the nasal cavity. The iguana then exhales quickly to blow the salty solution (often called snalt) from the nostrils. This tends to result in a crusty white deposit around the iguana's nostrils and enclosure. Although this is often referred to as "sneezing", it is different from true sneezing, which may be indicative of a respiratory infection. Slang: Snalting, Snorting, Sneezing

Secondary Nutritional Hyoparathyroidism - Another name for Metabolic Bone Disease (see above).

Semen Plug - see Sperm Plug (below).

Shudder Bob - A head bob that is combined with rapid side-to-side movements of the head. Shudder bobs are more intense than ordinary head bobs, and often indicate that the iguana is feeling territorial, threatened, or annoyed. Shudder bobs are also used by males in displays to females during breeding season. For more information on iguana communication, see the Body Language page.

Smeg (Smeggies) - See Sperm Plug (below).

Snalting - See Salt Expulsion (above).

Sneezing - See Salt Expulsion (above).

Snorting - See Salt Expulsion (above).

Snout Tail Length - See STL (below).

Snout Vent Length - See SVL (below).

Spay - See Hysterectomy (above).

Sperm plug - Sperm plugs are "packets" of sperm produced by male iguanas during breeding season and often deposited around their enclosure or habitat. Sperm plugs can be a variety of colors (white, off-white, orangey) and consistencies (soft or hard and dry), depending upon their freshness. Slang: smeg or smeggies. For more information on sperm plugs, see the Breeding Season Issues page.

Spikes - Refers to the projections present along the iguana's back. See the Anatomy page for photo.

Sterilize - The process of treating a non-living object with a substance that will completely destroy all bacteria and other microorganisms. This is not the same as disinfecting (see above). For more information, visit the Cleaning and Cleanliness page.

STL - An abbreviation for Snout Tail Length. This is one of the most common ways to measure an iguana's size. It indicates total length, including the tail. A more accurate measurement of size is Snout Vent Length or SVL (see below).

Stomatitis - Another name for Mouth Rot (see above).

Styptic Powder - A powder that is used to stop bleeding on small wounds such as torn toenails. For more information on Styptic Powder, see the First Aid Kit page.

Subcutaneous (SC) - A term that means "under the skin". This term is often used in reference to certain types of injections that a vet or owner may be required to give to an ill iguana.

Substrate - Refers to the substance lining the bottom of an iguana's enclosure, such as indoor/outdoor carpet, newspaper, etc.

SVL - An abbreviation for Snout Vent Length. This is one of the most common ways to measure an iguana's size. It indicates the length from the snout to the vent, and is more accurate than Snout Tail Length, or STL (see above), because tails often break. Broken tails can lead to an underestimation of iguana size. For that reason, SVL is preferred.

Subtympanic Scale - The large, slightly cone-shaped scale that lies under the lower jaw, on the jowls. This large scale is found only in the green iguana (Iguana iguana) and is indicative of the species. See the Anatomy page for photo.

Thermoregulate - The act of regulating body temperature. Because iguanas are ectothermic (see above), they must regulate their body temperature by their behavior - basking to warm up, and moving to cooler areas to cool down.

Thiamin - Another name for Vitamin B1. Thiamin is a necessary component of the diet, and is destroyed by the process of freezing foods. Iguana foods that are frozen and thawed before serving must be supplemented with thiamin or brewer's yeast (see above).

Third Eye - see Parietal Eye (above).

Tongue Flick - When an iguana briefly extends its tongue into the air or onto an object of interest. Tongue flicking gathers environmental information that is then transferred to the Jacobson's organ (see above) on the roof of the mouth.

Toxic - Poisonous or hazardous to one's health.

Tube lights - A slang term for UV fluorescent light bulbs (see above). Also sometimes written or referred to as toob lights.

Tuberculate Scales - The pyramid-shaped, bumpy scales along the side of the neck. See the Anatomy page for a photo.

Tympanum - The ear drum, which is visible on the side of the head. See the Anatomy page for a photo.

Ulcerative Stomatitis - Another name for Mouth Rot (see above).

Ultraviolet light (UV light) - Wavelengths of light that are slightly shorter than visible light waves on the violet end of the light spectrum. There are different forms of ultraviolet light, but when referring to iguanas, the term is usually used in reference to ultraviolet B (UVB). In iguanas, UVB triggers chemical reactions in the skin which lead to the formation of vitamin D3 (see below), which is used by the body to properly absorb calcium from the blood. Ultraviolet light is an essential part of an iguana's environment, and can be obtained from unfiltered sunlight or artificial UV bulbs. For more information on the importance of ultraviolet light, see the Habitat page.

Urates - The white, semi-solid part of the waste. Iguana kidneys secretes wastes mostly in the form of uric acid crystals. Normal waste from the kidneys consists of the semi-solid urates as well as a varying amount of liquid urine. Urates, urine and feces (from the digestive tract) are usually voided from the vent (see below) all at once.

Vent - Refers to the cloaca, or common opening for the urinary, digestive and reproductive systems. In iguanas, the vent is located on the ventral, or belly, side of the animal, at the base of the tail. It is through this opening that iguanas secrete urates (see above) from the kidneys and solid wastes from the digestive tract. In males, the hemipenes extrude through the vent during mating, and in females, the vent receives sperm during mating.

Vitamin D3 - A form of vitamin D that is manufactured by iguanas upon exposure to UV light (see above). Vitamin D3 is necessary for iguanas to properly absorb and use calcium in the body. Since it is still unclear whether or not iguanas can use vitamin D3 that is avaliable in the foods they eat, it is best to provide them with the opportunity to bask in UV light so they can make the needed amounts of vitamin D3 themselves.

Vomeronasal Organ - See Jacobson's Organ (above).

Worms - A common term applied to any long, cylindrical animal. In iguanas, various types of worms, such as tapeworms and pinworms, can be internal parasites (see above). For more information on worms, visit the Parasites page.