Protosialis casca
Encyclopedia
Protosialis casca is an extinct species
of alderfly
in the Sialidae subfamily Sialinae. The species is solely known from the early Miocene
, Burdigalian
stage, Dominican amber
deposits on the island of Hispaniola
. Protosialis casca is one of only two known alderfly species present in the West Indies, the only other species is the living Protosialis bifasciata native to Cuba.
, number "Mact 2090", which is a single male specimen currently residing in the private collection owned by Ettore Morone of Turin, Italy, and was first studied by Michael Engel
and David Grimaldi. Engel and Grimaldi's 2007 type description paper was published in the journal American Museum Novitates
. The specific epithet
"casca" was derived by the authors from the Latin
, which translates to "old" in reference to the age of the specimen.
When first described P. casca was named Sialis (Protosialis) casca by Engel and Grimaldi. They used the alderfly classification system put forth by Dr. Michael Whiting
in his 1994 paper on the phylogeny of North American
alderflies which treated Protosialis as a subgenus of Sialis. Currently most taxonomists treat Protosialis as a separate genus from Sialis making this species Protosialis casca and Sialis (Protosialis) casca a synonym.
of the forewing are unique to the genus Protosialis. The legs display black and white color patterning, with the area of the protibia and mesotibia white and the rest of the leg is black. The wing membranes are overall a dusky brownish gray, with veins a darker brow to black. The abdomen, light brown in color, is bend downwards near the midpoint and slightly distended.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of alderfly
Alderfly
Alderflies are megalopteran insects of the family Sialidae. They are closely related to the dobsonflies and fishflies as well as to the prehistoric Euchauliodidae. All living alderflies - about 66 species altogether - are part of the subfamily Sialinae, which contains between one and seven extant...
in the Sialidae subfamily Sialinae. The species is solely known from the early Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
, Burdigalian
Burdigalian
The Burdigalian is, in the geologic timescale, an age or stage in the early Miocene. It spans the time between 20.43 ± 0.05 Ma and 15.97 ± 0.05 Ma...
stage, Dominican amber
Dominican amber
Dominican amber is amber from the Dominican Republic. Resin from the extinct species Hymenaea protera is the source of Dominican amber and probably of most amber found in the tropics....
deposits on the island of Hispaniola
Hispaniola
Hispaniola is a major island in the Caribbean, containing the two sovereign states of the Dominican Republic and Haiti. The island is located between the islands of Cuba to the west and Puerto Rico to the east, within the hurricane belt...
. Protosialis casca is one of only two known alderfly species present in the West Indies, the only other species is the living Protosialis bifasciata native to Cuba.
History and classification
The species is known only from the holotypeHolotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
, number "Mact 2090", which is a single male specimen currently residing in the private collection owned by Ettore Morone of Turin, Italy, and was first studied by Michael Engel
Michael S. Engel
Michael S. Engel is an American paleontologist and entomologist. He has undertaken field work in Central Asia, Asia Minor, and the Western Hemisphere, and published more than 300 papers in scientific journals. He was trained at the University of Kansas where in 1993 he received a B.S. in Cellular...
and David Grimaldi. Engel and Grimaldi's 2007 type description paper was published in the journal American Museum Novitates
American Museum Novitates
American Museum Novitates is an academic journal published by the American Museum of Natural History. The journal was founded in 1921....
. The specific epithet
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
"casca" was derived by the authors from the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
, which translates to "old" in reference to the age of the specimen.
When first described P. casca was named Sialis (Protosialis) casca by Engel and Grimaldi. They used the alderfly classification system put forth by Dr. Michael Whiting
Michael F. Whiting
Michael F. Whiting is the director of the Brigham Young University DNA Sequencing Center and an associate professor in BYU's Department of Integrative Biology. Whiting received his bachelors degree from BYU and his Ph.D...
in his 1994 paper on the phylogeny of North American
North American
North American generally refers to an entity, people, group, or attribute of North America, especially of the United States and Canada together.-Culture:*North American English, a collective term used to describe American English and Canadian English...
alderflies which treated Protosialis as a subgenus of Sialis. Currently most taxonomists treat Protosialis as a separate genus from Sialis making this species Protosialis casca and Sialis (Protosialis) casca a synonym.
Description
The holotype of Protosialis casca is 7.6 millimetre (0.299212598425197 in) in length with a forewing length of between 7.7–8.4 mm (0.303149606299213–0.330708661417323 in). The forewing length cannot be determined more precisely due to the apical portions of the wings being missing. The orange and black coloration of the head and pronotum combined with the reduced number of crossveins in the costal regionInsect wing
Insects are the only group of invertebrates known to have evolved flight. Insects possess some remarkable flight characteristics and abilities, still far superior to attempts by humans to replicate their capabilities. Even our understanding of the aerodynamics of flexible, flapping wings and how...
of the forewing are unique to the genus Protosialis. The legs display black and white color patterning, with the area of the protibia and mesotibia white and the rest of the leg is black. The wing membranes are overall a dusky brownish gray, with veins a darker brow to black. The abdomen, light brown in color, is bend downwards near the midpoint and slightly distended.