Most araneomorphs breath through a single pair of anterior book lungs and air tubes tracheae that evolved from the posterior book lungs and which allow more efficient gas exchange. Tarantulas comprise a group of large and often hairy arachnids belonging to the theraphosidae family of spiders, of which about 900 species have been identified. There are two pairs of book lungs in mygalomorph and some araneomorph spiders. What you found is likely one of the non tarantula mygalomorphs. Araneomorphae which encompasses most of the spider species. The epigastric furrow is an opening between the set of book lungs closest to the cephalothorax body of the spider. It also internally contains the heart, reproductive organs, and the midgut. One group, the australian theraphosids or tarantulas, are also known as whistling spiders. Almost routinely, these physiologists are unconcerned with tarantula taxonomy. Mygalomorph article about mygalomorph by the free dictionary. In all types of tarantula there are two sets of book lungs breathing organs. The geographic location of the specimens they use are rarely mentioned, except most are probably from the us.
Tarantulas are big and hairy but not so scary howstuffworks. Setaestiff, bristle like structure serving as organs of touch, hearing and smell 3. Many mygalomorph taxa are dispersallimited, and regionallyendemic, and have long been favorites of biogeographers. Familiar mygalomorphs include tarantulas also called baboon spiders and trapdoor spiders, but many other distinctive taxonomic groups exist. These spiders are related to tarantulas all being mygalomorphs, but are classified in different families. Mygalomorphs are mostly heavily built, often quite slow moving and are burrowdwelling. The images on this website are merely a small crosssection of the species and images found in rick wests photo collection. This group of spiders comprises mostly heavybodied, stoutlegged spiders including tarantulas, australian funnelweb spiders, mouse spiders, and various families of spiders commonly called trapdoor spiders like the primitive suborder of spiders mesothelae, they have two pairs of book lungs, and downwardpointing chelicerae. All mygalomorphs have two pairs of book lungs, whereas all. Tarantulas are distinguished from other mygalomorphs by a collection of traits that include not only their size and hairiness but also their two pairs of book lungs and their threesegmented spinnerets. Dec 18, 2008 mygalomorphs are spiders that have fangs that fold with the axis of the body and strike in a stabbing motion, and have two pairs of book lungs. Australian mygalomorph groups include trapdoor, funnelweb, wishbone, curtainweb and mouse spiders. Some flies in the family acroceridae that are endoparasites of mygalomorphs may remain dormant in their book lungs for as long as 20 years before beginning their development and consuming the spider. The mesothelae are a suborder of spiders order araneae that includes a single living extant family, liphistiidae, and a number of extinct families.
The spiders, which are distributed in the tropics, hunt at night for insects, small frogs and lizards, and, sometimes, small birds. They are distinguished by having chelicerae fangs that point diagonally forward and cross in a pinching action, in contrast to the mygalomorphae tarantulas. Basal metabolic rate, oxygen uptake of animals at rest as measured bymanometric respirometry, was very low in both species mostly well below 1 ml o2 stpdh. Tarantulas are big and hairy but not so scary by jesslyn shields aug 15, 2019 the mexican redkneed tarantula brachypelma smithi is a terrestrial tarantula native to the deserts, scrublands and mountain ranges of mexico. Their fangs point backwards towards the rear of the body rather than towards each other as in the araneomorphs. May 28, 2016 the worlds largest tarantula has been living in our walls. In mygalomorphs they work parallel to each other, stabbing downward. Internal construction of tarantula lungs presents itself the grouped plateform fine membranes lamella, reminding pages of ajar book, inwardly which circulates the hemolymph, substituting carbon dioxide by oxygen, got from air. A slightly indepth guide to tarantula anatomy and taxonomic. Internal anatomy theraphosids tarantulas of the world. While the behaviour of tarantulas can vary, many make burrows in soil and feed mainly at night on insects and occasionally small frogs, toads, and mice. Morphology and evolution of spider book lungs institut fur biologie.
Oxygen consumption, book lungs, mygalomorph spider. Evolution and 400 million years of spinning, waiting, snagging, and mating an excellent gift idea. Trapdoor spiders a family of mygalomorphs wandering spiders includes some very. A book lung is a type of respiration organ used for atmospheric gas exchange that is found in. Book lungs are stacks of ten to eighty hollow, leafy disks. Each book lung consists of multiple folds of tissue lamellae through which air flows.
She then digs a hole and puts the spider and an egg into it. As to the fangs chelicerae in araneomorphs they work in opposition to each other, grasping toward the center. Cheliceraepair of appendages used for seizing and crushing prey 4. Mygalomorph spiders have long, fingerlike spinnerets, which are frequently easy to see from above. Haplogyne spiders, such as mygalomorphs and some araneomorphs, possess a more primitive female genital anatomy than the rest of the araneomorph families, which are entelegyne spiders. The natural history of tarantula spiders richard c. Viewers are welcome to use this website as an identification tool, however, viewers must realize that although many tarantulas are colourpattern specific, identifications can never be positively made from images alone. This article only describes members of the theraphosidae, although some other members of the same infraorder mygalomorphae are commonly referred to as tarantulas.
Mygalomorphae definition is a suborder of spiders comprising those in which the fangs move vertically and four book lungs are present. Predators that the tarantula would be afraid of are weasels, hawks, owls, skunks and snakes. Basal metabolic rate, oxygen uptake of animals at rest as measured bymanometric respirometry, was very low in both species mostly well below 1 ml. This suborder is thought to form the sister group to all other living spiders, and to retain ancestral characters, such as a segmented abdomen with spinnerets in the middle and two pairs of book lungs. Mygalomorphs are primitive forms having 4 book lungs, while araneomorphs are true spiders with 2 book lungs. These spiders are related to true tarantulas all being mygalomorphs, but are classified in different families. Because of this, the two groups were once believed to. Most of the blood returning to the heart passes through the book lungs, where it becomes oxygenated. Tarantula, family theraphosidae, any of numerous hairy and generally large spiders found in the southwestern united states, mexico, and tropical america.
Considered an ancient monophyletic group, mygalomorphs retain several characteristics that are considered primitive for spiders, e. The small crevice in between the first pair of book lungs houses two small sacs, the spermatheca, used to receive and store sperm from the male. The opisthosoma houses the two pairs of book lungs, a primitive respiratory system consisting of ventilated, leaflike lungs through which air circulates. For a wonderful read about the evolution of spiders and their silk, including lots more information that i didnt include about the fascinating habits of mygalomorphs, i highly recommend leslie brunetta and catherine craigs book spider silk. Introduction in this article i have attempted to present a varied, fresh account of what a tarantula is and what it does. Most folks are familiar with tarantulas which are found more in warmer climates, but these lesserknown mygalomorphs can be found right here in western pa. Spiders are divided into three suborders, the mesothelae, mygalomorphae, and araneomophae, and 106 families. If you have a photo, i could try to identify it for you. Despite this variety, however, the spider body is fairly uniform, consisting of a prosoma which mainly serves sensory and locomotory functions. Unlike an insect, the spiders body is in two sections. The mygalomorphae, or mygalomorphs, are an infraorder of spiders. The spinnerets can be found externally on this part of the tarantulas body. This allows araneomorphs to be less sedentary than mygalomorphs. The female wasp will paralyze the spider by stinging it.
These are respiratory structures known as book lungs. Organs include brain, heart, eyes, poison glands, digestive tubes, book lungs, ovaries and silk glands. They have two pairs of book lungs and usually only. Nontarantula spiders infraorder with 2 book lungs, tracheae, 6 spinnerets, diaxial fangs. Tarantulas are mygalomorphs suborder orthognatha, and thus they have jaws that move forward and down rather than sideways and together. The name tarantula is also incorrectly applied to other largebodied spiders, including the purseweb spiders or atypical tarantulas, the funnelwebs dipluridae and hexathelidae, and the dwarf tarantulas. Mygalomorph spiders have long, fingerlike spinnerets, which are. Chapter 2 the circulatory system of spiders christian s. Scientists have found that many primitive spider species have the feature of a set of book lungs compared to just one pair. Trapdoor spiders, australasian funnel web spiders, purseweb spiders, and mouse spiders are also mygalomorphs. Lungs of modern spiders were formed from abdominal gills drumsticks of their water ancestors. When the egg hatches, the baby wasp will eat away at the paralyzed spider. Oxygen uptake, carbon dioxide release, water release and heart frequency were studied in the tarantula,eurypelma californicum. A reconsideration of the classification of the spider.
Orbweb and hunting spiders belong to the araneomorph category. They have two pairs of book lungs and usually only four or even as few as two spinnerets. Other mygalomorphs tarantulas, bird spiders rick west. Mygalomorphae definition of mygalomorphae by merriamwebster. Mygalomorphs are spiders that have fangs that fold with the axis of the body and strike in a stabbing motion, and have two pairs of book lungs. Pdf respiratory refinements in the mygalomorph spider.
The book lungs are located in the anterior portion of the abdomen and open to the exterior through a pair of slitlike openings within the epigastric furrow. Book lungrespiratory structure made up of thin, flat folds of tissue arranged like a book s pages. Raven 1985, mygalomorphs retain several characteristics that are considered primitive for spiders e. Aug 15, 2019 tarantulas are big and hairy but not so scary by jesslyn shields aug 15, 2019 the mexican redkneed tarantula brachypelma smithi is a terrestrial tarantula native to the deserts, scrublands and mountain ranges of mexico. Air enters the cavity through a tiny slit on each side of and near the front of the abdomen. Folks using this method will compare the curve of the furrow, the distance between the anterior book lungs, and the angle of the lungs to determine gender. Most mygals are relatively large, longlived 1530 years, ground dwelling spiders the largest spiders in the world are in fact mygalomorphs. Theraphosidae one of several families within the mygalomorphae is the familial name of the tarantulas. Many mygalomorphs are longlived, with the females of some species known to live for 25 years. Book lungrespiratory structure made up of thin, flat folds of tissue arranged like a books pages. The number of hollow disks stacked depends on the species of spider.
This article although laden with jargon will hopefully provide snippets of interesting information for those interested in tarantulas theraphosids. In this spider diagram, the book lung is labelled 1. Sac spiders closely related to clubionidae tarantulas infraorder family for yellow sac spiders. But the araneomorphs are sort of the figurehead group of the order araneae spiders.
At the outset, note that it is important to know the sex of your spider. The name tarantula is also applied to other largebodied spiders, including the purseweb spiders or atypical tarantulas, the funnelweb tarantulas dipluridae and hexathelidae, and the dwarf tarantulas. The worlds largest tarantula has been living in our walls. The araneomorphae also called the labidognatha are an infraorder of spiders. In all types of tarantulas there are two book lungs breathing organs. Tarantula respiration since tarantulas are large and much easier to study, many physiologists interested in spider respiration end up using them. Oxygen uptake also was studied in the scorpion,pandinus imperator.
The first pair of book lungs is located in a cavity inside the lower front part of the abdomen near where the abdomen connects to the cephalothorax and the second pair slightly farther back on the abdomen. True spiders have only one set of book lungs or none at all. Not true spiders, tarantulas belong to the superfamily mygalomorphae and are often referred to as hairy mygalomorphs true spiders belong to the superfamily araneomorphae. T o date, 43,678 species in 3898 genera and 112 families of spider have been recorded from around the world platnick. The mesothelae 1 family, liphistiidae, 2 genera, 40 species are considered the most primitive of all living spiders, based on their external visible segmentation and location and number of spinnerets all four pairs present, without a cribellum. In mygalomorph spiders, respiration involves the movement of gases across an exchange. Also, the month that has the most precip june, theres still barely 1.
Mygalomorphs include the tarantulas, trapdoor spiders, mouse spiders, purseweb spiders, and baldlegged spiders. Mygalomorphic spiders have two pairs of book lungs, and large chelicerae bearing parallel fangs that move up and down rather than sideways, as they do in araneomorphic spiders. The group that contains mygalymorphs and araneomorphs. Scientists have found that many primitive spider species have the feature of a set of. Dec 16, 20 for a wonderful read about the evolution of spiders and their silk, including lots more information that i didnt include about the fascinating habits of mygalomorphs, i highly recommend leslie brunetta and catherine craigs book spider silk. The book lungs are saturated in light blue haemolymph. They have four book lungs, named after their resemblance to the pages of a book. While the behaviour of tarantulas can vary, many make burrows in soil and feed mainly at night on insects and occasionally small frogs, toads. The book lungs are located in a cavity inside the lower front part of the abdomen near where the abdomen connects to the cephalothorax. Tarantula relative found at powdermill carnegie museum of. Jun 18, 2018 tarantulas are distinguished from other mygalomorphs by a collection of traits that include not only their size and hairiness but also their two pairs of book lungs and their threesegmented spinnerets. Nearly all spiders have a pair of book lungs, but only the primitive groups have two pairs.
The examples of mygalomorphs are tunnelweb and tarantula spiders. The tarantula is a very large type of spider, but this one has to be a record. Tarantulas are mygalomorphs suborder orthognatha, and thus they have jaws that move forward and down rather than sideways and together, which is. Each organ is colored for identification not realistically and they nest together nicely inside so you can see how the body systems would be in place.
The ultrastructure of the book lungs of the italian trapdoor. Tarantulas are mygalomorphs, along with their close cousins the trapdoor spiders, the purseweb spiders, and the foldingdoor spiders. Two pairs of book lungs are retained in meso theles and mygalomorphs, and among the. These book lungs allow air to enter and circulate around thin plates which are richly supplied with hemolymph blood.