Arachnida is a class of joint-legged invertebrate animals (arthropods), in the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, harvestmen, camel spiders, whip spiders and vinegaroons.
The Opiliones are an order of arachnids colloquially known as harvestmen, harvesters, harvest spiders, or daddy longlegs. As of April 2017, over 6,650 species of harvestmen have been discovered worldwide, although the total number of extant species may exceed 10,000. The order Opiliones includes five suborders: Cyphophthalmi, Eupnoi, Dyspnoi, Laniatores, and Tetrophthalmi, which were named in 2014.
Laniatores is the largest suborder of the arachnid order Opiliones with over 4,000 described species worldwide. The majority of the species are highly dependent on humid environments and usually correlated with tropical and temperate forest habitats.
Gonyleptidae is a neotropical family of harvestmen with more than 800 species, the largest in the Suborder Laniatores and the second largest of the Opiliones as a whole. The largest known harvestmen are gonyleptids.
The opisthosoma is the posterior part of the body in some arthropods, behind the prosoma (cephalothorax). It is a distinctive feature of the subphylum Chelicerata. Although it is similar in most respects to an abdomen, the opisthosoma is differentiated by its inclusion of the respiratory organs and the heart.
Cosmetidae is a family of harvestmen in the suborder Laniatores. With over 700 species, it is one of the largest families in Opiliones. They are endemic of the New World with a Nearctic-Neotropical distribution where a large fraction of the diversity of Opiliones are represented by this single family. Cosmetidae have the northern extent of their range into the USA, where a small number species occur in the southern states. However, the family is especially diverse in Mexico, Central America and northern South America; especially the Andean realms. Their range also extends further south into Argentina and southern Brazil, but they are absent in Chile. Cosmetidae are prevalent in Amazonian region, but only relatively few also occur in Brazilian Atlantic Forest. Several species are also found in the Caribbean.
The Eupnoi are a suborder of harvestmen, with more than 200 genera, and about 1,700 described species.
Cyphophthalmi is a suborder of harvestmen, colloquially known as mite harvestmen. Cyphophthalmi comprises 36 genera, and more than two hundred described species. The six families are currently grouped into three infraorders: the Boreophthalmi, Scopulophthalmi, and Sternophthalmi.
The Neopilionidae are a family of harvestmen.
An ozopore is the opening of a defensive gland present in some arthropods, notably in millipedes of the order Polydesmida and in harvestmen, the eight-legged arachnids also known as "daddy long-legs". The glands themselves are known as ozadenes, also called "scent glands", "repugnatorial glands", "odoriferous glands" or "stink glands" by various authors. The name is derived from Ancient Greek ozo "smell" and Latin porus "pore, small opening".
Nipponopsalididae is a family of harvestmen with three described species in one genus, Nipponopsalis, which is found in East Asia.
Assamiidae are a family of harvestmen with more than 400 described species. It is the third most diverse family of the suborder Laniatores.
The Fissiphalliidae are a small neotropical family of harvestmen within the suborder Laniatores.
Stomotheca is the term applied to the feeding apparatus in front of the mouth of harvestmen, and sometimes the related scorpions. Usually it consists of the epistome (labrum), two pairs of coxapophyses and often a labium.
Opiliones are an order of arachnids and share many common characteristics with other arachnids. However, several differences separate harvestmen from other arachnid orders such as spiders. The bodies of opiliones are divided into two tagmata : the abdomen (opisthosoma) and the cephalothorax (prosoma). Unlike spiders, the juncture between the abdomen and cephalothorax is often poorly defined. Harvestmen have chelicerae, pedipalps and four pairs of legs. Most harvestmen have two eyes, although there are eyeless species.
Harvestmen (Opiliones) are an order of arachnids often confused with spiders, though the two orders are not closely related. Research on harvestman phylogeny is in a state of flux. While some families are clearly monophyletic, that is share a common ancestor, others are not, and the relationships between families are often not well understood.
An intromittent organ is any external organ of a male organism that is specialized to deliver sperm during copulation. Intromittent organs are found most often in terrestrial species, as most non-mammalian aquatic species fertilize their eggs externally, although there are exceptions. For many species in the animal kingdom, the male intromittent organ is a hallmark characteristic of internal fertilization.
Quindina albomarginis is a species of Neotropical harvestman in the order Opiliones. It is found in the tropical forests of Panama.
Travunioidea is a superfamily of armoured harvestmen in the order Opiliones. There are 4 families and more than 70 described species in Travunioidea.
Pantopsalis listeri is a species of harvestman in the family Neopilionidae.
