These structures are more prominent in females. The spiders rub these structures with a matching pair of sclerotized plates at the anterior portion of the abdomen, producing sound. The first type is located at the posterior tips of their cephalothorax (the prosoma) in the form of two triangular protrusions. They also possess two types of stridulatory organs. The abdomen is angular and somewhat box-shaped, with a small conical hump on the upper back. An irregular darker stripe runs lengthwise at the bottom surface. The abdomen (the opisthosoma) is gray with white lateral stripes and various dark and light patches on the sides and the upper surface. They are pearly-white in color and located at the tip of the cephalothorax in two lines. lyoni, like most other cellar spiders, has eight eyes. In the middle of the upper surface is a deep depression (called the thoracic fovea) and a darker longitudinal band of color. The cephalothorax is wider than it is long, greyish-white to pale amber in color. Their leg formula is I, II, IV, III - the front pair of legs being the longest and the third pair being the shortest. Males also possess a series of 20 to 25 spines ( macrosetae) on their femur. The 'knee joints' are brown, and the ends of the femur and tibiae are girdled with white. The legs are gray to amber in color and covered with numerous small longitudinal brown spots. The first pair of legs in larger male individuals can reach up to 6 centimetres (2.4 in) in length. Males have slightly longer legs than females. Both sexes possess extremely long fragile legs. Males are slightly smaller, at about 2.5 to 6 mm (0.098 to 0.236 in) in length, and have prominent pedipalps. lyoni are about 3 to 7 mm (0.12 to 0.28 in) in length. (Both specimens from the Philippines) Crossopriza lyoni from India. Left: Male tailed cellar spiders are recognizable by the enlarged pedipalps. īlackwall also described a curious case of hermaphroditism in one adult specimen, in which the left side was male and the right side was female. In 1892, the French arachnologist Eugène Simon erected the genus Crossopriza and subsequently reclassified Pholcus lyoni to Crossopriza lyoni. He classified the species under the genus Pholcus. Blackwall named the spider after Captain Lyon and expressed a hope that others may follow Lyon's example in collecting specimens from foreign countries for the benefit of science. They were sent to his sister who presented them to Blackwall at the suggestion of a mutual friend. They came from Francis Lyon, a captain of the Royal Artillery of the British Empire stationed in India. The species was first formally described in 1867 by the British naturalist John Blackwall from a collection of spiders from Meerut, Agra, and Delhi. However, they are not closely related to cellar spiders - the latter is a fly and the former, while also an arachnid, is not a spider at all. lyoni and other cellar spiders are also often confused with two other invertebrates - the harvestmen ( order Opiliones) and the crane flies (family Tipulidae) - both of which are also known as 'daddy longlegs'. They are commonly referred to as tailed daddy longlegs spiders, tailed cellar spiders, or (more rarely) box spiders. They belong to the cellar spider family ( Pholcidae). They are harmless to humans.Ĭrossopriza lyoni are classified under the genus Crossopriza and the subfamily Holocneminae. Some people, however, regard them as beneficial, as they are efficient predators of mosquitoes and other arthropods. They are a regulated species in some countries and are often regarded as pests due to the large amounts of unsightly webs they construct inside human homes. They have been introduced into other parts of the world accidentally and are now pantropical in distribution. They also possess two kinds of sound-producing organs and have six eyes. Their abdomens are distinctly squarish when viewed from the side and their carapace is more or less circular when viewed from above. They all possess extremely long fragile legs that can reach up to 6 cm (2.4 in) long and a body length of that ranges from 2.5 to 7 mm (0.098 to 0.276 in). They are commonly known as tailed cellar spiders, tailed daddy longlegs spiders, and sometimes box spiders. Crossopriza lyoni is a widespread species of cellar spiders that prefer to live in or around human structures.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |