| Allacma fusca | |
|---|---|
 | |
| Allacma fusca on rotting wood | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Collembola |
| Order: | Symphypleona |
| Family: | Sminthuridae |
| Genus: | Allacma |
| Species: | A. fusca |
| Binomial name | |
| Allacma fusca | |
Allacma fusca is a species of springtail. This species is endemic to western areas of Continental Europe and the British Isles, [1] [2] where it lives in the surface layers of the soil in moist habitats such as among leaf litter.
Allacma fusca is a large species of springtail with a dark brown globular abdomen; adults reach a length of around 3.5 mm (0.14 in). [3] There is often a "snowflake"-like marking on the abdomen, which is most noticeable in paler coloured individuals. [4] The mouthparts are internal, and the head bears a pair of antennae, two groups of eyespots known as "composed eyes" and a pair of small post-antennal organs. The setae (bristles) on the third antennal segment are unequal in length, some being much longer than others, and the fourth antennal segment is divided into sixteen sub-segments. There are three thoracial segments, each bearing a leg, and five abdominal segments. The fourth abdominal segment bears an organ known as a "dens", and at the tip of this is a structure known as a "mucro". This species has mucros with smooth outer edges and saw-edged inner edges. In females, the appendage on the fifth abdominal segment is unforked. [3] [5]
This springtail is native to Western Europe. It is common in the British Isles and inhabits moist terrestrial environments such as plant litter. [3]
Invertebrates living among the soil particles in underground habitats often experience raised levels of carbon dioxide, which tends to increase with depth. Researchers have found that the surface-dwelling Allacma fusca can tolerate a 10% level of carbon dioxide for a few hours while in contrast, the springtail Folsomia candida , which lives deeper in the soil, can survive under the same conditions for more than six weeks. [6]
The order Diplura is one of three orders of non-insect hexapods within the class Entognatha. The name "diplura", or "two tails", refers to the characteristic pair of caudal appendages or filaments at the terminal end of the body.
The Protura, or proturans, and sometimes nicknamed coneheads, are very small, soil-dwelling animals, so inconspicuous they were not noticed until the 20th century. The Protura constitute an order of hexapods that were previously regarded as insects, and sometimes treated as a class in their own right.
The abdomen is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal cavity. In arthropods, it is the posterior tagma of the body; it follows the thorax or cephalothorax.
Entomobryidae, sometimes called "slender springtails", is a family of springtails characterised by having an enlarged fourth abdominal segment and a well-developed furcula. Species in this family may be heavily scaled and can be very colourful. The scale-less Entomobryidae are commonly caught in pitfall traps around the planet, and also occur in canopy faunas high up in trees. There are more than 1700 described species in Entomobryidae.
The Entognatha are a class of wingless and ametabolous arthropods, which, together with the insects, makes up the subphylum Hexapoda. Their mouthparts are entognathous, meaning that they are retracted within the head, unlike the insects. Entognatha are apterous, meaning that they lack wings. The class contains three orders: Collembola, Diplura and Protura. These three groups were historically united with the now-obsolete order Thysanura to form the class Apterygota, but it has since been recognized that the hexapodous condition of these animals has evolved independently from that of insects, and independently within each order. The orders might not be closely related, and Entognatha is now considered to be a paraphyletic group.
Dolichopodidae, the long-legged flies, are a large, cosmopolitan family of true flies with more than 8,000 described species in about 250 genera. The genus Dolichopus is the most speciose, with some 600 species.
The anatomy of spiders includes many characteristics shared with other arachnids. These characteristics include bodies divided into two tagmata, eight jointed legs, no wings or antennae, the presence of chelicerae and pedipalps, simple eyes, and an exoskeleton, which is periodically shed.
The furcula, or furca is a forked, tail-like appendage. It is present in most species of springtails, and in them it is attached ventrally to the fourth abdominal segment. The organ most often is present in species of Collembola that lives in the upper soil layers where it is used for jumping to avoid predators. While at rest, it is retracted under the abdomen and held there by a structure variously called the retinaculum or hamula, which in turn is located beneath the third abdominal segment. When the furcula escapes from retinaculum, it swings downwards and hits the substrate, propelling the springtail into the air. The animal does not use this mechanism for ordinary locomotion, but only for escaping from predators or severe stress.
Eucrenonaspides oinotheke is a species of crustacean in the family Psammaspididae, endemic to Tasmania, the only species described in the genus Eucrenonaspides. Eucrenonaspides is in the order Anaspidacea. It was described from a spring at 9 Payton Place, Devonport, Tasmania in 1980, making it "the first spring-dwelling syncarid recorded from the Australian region". It is listed as a vulnerable species on the IUCN Red List. A further undescribed species is known from south-western Tasmania.
Anurida maritima, the seashore springtail, is a cosmopolitan collembolan of the intertidal zone. It is often found in aggregations of up to several hundred on the surface of rock-pools.
Homidia pentachaeta is a species of soil-dwelling springtail belonging to the family Entomobryidae. It is only known from its type location in the vicinity of Nanjing, People's Republic of China.
Springtails form the largest of the three lineages of modern hexapods that are no longer considered insects. Although the three orders are sometimes grouped together in a class called Entognatha because they have internal mouthparts, they do not appear to be any more closely related to one another than they are to all insects, which have external mouthparts.
Sminthuridae, not to be confounded with: Sminthurididae, is a family of springtails of the order Symphypleona. Sminthurids are commonly referred to as globular springtails.
Orchesella cincta is a species of springtail present in North America and Europe. They average 4 millimetres (0.16 in) in length, which is extremely large as most springtails don’t grow past 1 millimetre. The specific name cincta means "belted" and refers to the distinctive colouration of the third abdominal segment.
Folsomia candida is a species of springtail in the family Isotomidae. It is found in soil in many locations around the world, having been spread inadvertently by humans. It reproduces by parthenogenesis and has been used as a model organism in research.
The Tridactylidae are a family in the insect order Orthoptera. They are small, mole-cricket-like insects, almost always less than 20 mm (0.79 in) long when mature. Generally they are shiny, dark or black, sometimes variegated or sandy-coloured. They commonly live in short tunnels and are commonly known as pygmy mole crickets, though they are not closely related to the true "mole crickets" (Ensifera), as they are included in the Caelifera suborder.
The subphylum Hexapoda or hexapods comprises the largest clade of arthropods and includes most of the extant arthropod species. It includes the crown group class Insecta, as well as the much smaller clade Entognatha, which includes three classes of wingless arthropods that were once considered insects: Collembola (springtails), Protura (coneheads) and Diplura. The insects and springtails are very abundant and are some of the most important pollinators, basal consumers, scavengers/detritivores and micropredators in terrestrial environments.
Entomobrya nivalis, the cosmopolitan springtail, is a species of slender springtails in the family Entomobryidae.
Willowsia buski, the damp grain springtail, is a species of slender springtail in the family Entomobryidae. It is found in abundance throughout North America and Europe, and likely has a cosmopolitan distribution. It can sometimes be found infesting stores of dry goods that have become contaminated with high moisture, giving rise to the name "damp grain springtail".
Newsteadia floccosa, the boreal ensign scale, is a species of scale insect in the family Ortheziidae. It is native to Europe and is found in the soil and amongst plant litter and mosses on the ground.