| Neotrogla | |
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| (B) Neotrogla curvata, body length 3.5mm. (C) Neotrogla aurora, body length 2.8mm. | |
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| Genus: | Neotrogla Lienhard, 2010 [1] |
| Type species | |
| Neotrogla brasiliensis Lienhard, 2010 | |
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See text | |
Neotrogla is a genus of barklice noted for its reversed sex roles and organs, traits shared by all species of the genus.
Neotrogla are found in dry cave systems throughout Brazil. They feed primarily on bat guano. [2]
Neotrogla are about the size of fleas. [2] The genus can be distinguished from other genera of Speleketorinae by the presence of articulated spines on the anterior side of their legs, and by their unique genitalia. Both sexes have hairs on their tarsus, but the hairs on females are markedly longer. Neotrogla have branched hindwings and brown forewings. [1]
Female Neotrogla possess a penis-like organ, properly termed a "gynosome", [1] but also described by some as a "female penis". They aggressively seek out mates, while males are more selective. [3] During mating, the female mounts the male and penetrates his small genital opening from behind. Her gynosome swells and tiny barbs on the organ lock the individuals tightly together; when a researcher tried to separate mating individuals the male was torn in two, leaving his reproductive organs attached to the female. During mating, the female uses her gynosome to extract sperm and nutrient-filled seminal fluid from the male. A single mating session can last from 40 to 70 hours. [2]
The reversal of sex organs may be explained by the lack of nutrients in the cave environment, which makes it evolutionarily useful for the female to extract nutrients from the male. [4] Female Neotrogla drain males of seminal fluid even when they are too young to reproduce, giving weight to this theory, according to entomologist Kazunori Yoshizawa who co-authored the first study of the insects' mating behavior. If males spend most of their limited resources producing such nutrient-rich fluid, it would also help explain why males are choosy about their partners. Males of other insects are known to produce similar "nuptial gifts" of nutrients to be passed over during mating. [2] However, the evolutionary origin of the penis-like organ remains a complete mystery. "Usually, a new structure evolves as a modification of a previously existing structure," Yoshizawa explained. Such an adaptation would be "exceptionally difficult" because of the need for male and female genital structures to change at the same time. [4]
Female penetration of males is known in a few species, such as seahorse, but only Neotrogla females have a well-defined organ that can be described as a penis. [3] Likewise, reversal of sex roles has been recorded in a few other species of animals. Neotrogla, however, appears to be unique in having both traits. [2] According to Yoshizawa, the animal offers a singular chance to study the conflict between the sexes and the role of sexual selection in evolution. "It will be important to unveil why, among many sex-role-reversed animals, only Neotrogla evolved the elaborated female penis," he said. [5] In 2017, Kazunori Yoshizawa, Rodrigo Ferreira, Yoshitaka Kamimura and Charles Lienhard have been awarded an Ig Nobel Prize in biology "for their discovery of a female penis, and a male vagina, in a cave insect".
Scientists who study Neotrogla have occasionally called the gynosome a "female penis" [3] and insisted to drop the definition of penis as "the male copulatory organ". [6] Motivations for using the term “female penis” include that such a term "is easier to understand and much more eye-catching" [7] and that the gynosome have "analogous features" with male penises. [6] Meanwhile, critics have argued that it does not fit the intromittent organ definition of "a structure that enters the female genital tract and deposits sperm". [8]
Neotrogla was first spotted by ecologist Rodrigo Ferreira. [2] In 2010, entomologist Charles Lienhard assigned the insects to a new genus, designating Neotrogla brasiliensis as the type species. It was the first New World genus of Sensitibillini, a tribe of Speleketorinae previously known only from Africa. Neotrogla is closely related to the Southern African genus of barklice Afrotrogla . [1]
As of 2014, four species have been described: [1] [9]
Psocoptera are a paraphyletic group of insects that are commonly known as booklice, barklice or barkflies. The name Psocoptera has been replaced with Psocodea in recent literature, with the inclusion of the former order Phthiraptera into Psocodea.
A pseudo-penis is any structure found on an animal that, while superficially appearing to be a penis, is derived from a different developmental path.
Psocomorpha is a suborder of barklice, booklice, and parasitic lice in the order Psocodea. There are more than 20 families and 5,300 described species in Psocomorpha.
Trogiomorpha is one of the three major suborders of barklice, booklice, and parasitic lice in the order Psocodea, alongside Troctomorpha and Psocomorpha. There are about 8 families and more than 430 described species in Trogiomorpha. Trogiomorpha is widely agreed to be the earliest diverging of the three suborders, and retains the most primitive characteristics.
Troctomorpha is one of the three major suborders of Psocodea (barklice, booklice, and parasitic lice), alongside Psocomorpha and Trogiomorpha. There are more than 30 families and 5,800 described species in Troctomorpha. The order includes parasitic lice, which are most closely related to the booklice family Liposcelididae.
Amphipsocidae is a family of hairy-winged barklice in the order Psocodea. Most species are 3.0-4.5 mm long and have many setae (hairs) on the veins and margin of the forewing. The main veins of the forewing are usually lined with two rows of setae. Like the other members of the infra-order Caeciliusetae, they have a broad, flat labrum, with well defined edges.
Asiopsocidae is a family of Psocodea belonging to the infraorder Caeciliusetae. The family is composed of 14 known species of barklice in three genera: Asiopsocus, Notiopsocus, and Pronotiopsocus. One species from each genus has been found in the United States.
Ectopsocidae is a family of Psocodea belonging to the suborder Psocomorpha. The family includes fewer than 200 species, most of them in the genus Ectopsocus.
Lachesillidae is a family of Psocodea belonging to the suborder Psocomorpha. Members of the family are characterized by a rounded, free areola postica in their wings. Males have diverse sclerotized genitalic structures. The family includes more than 400 species, most of them in the genus Lachesilla.
Homilopscocidea is an infraorder of Psocodea. It is probably a paraphyletic group, still in use for lack of a better solution. There are about 7 families and more than 1,200 described species in Homilopsocidea.
A penis is a male sex organ that is used to inseminate female or hermaphrodite animals during copulation. Such organs occur in both vertebrates and invertebrates, but not in all male animals.
Psocodea is a taxonomic group of insects comprising the bark lice, book lice and parasitic lice. It was formerly considered a superorder, but is now generally considered by entomologists as an order. Despite the greatly differing appearance of parasitic lice (Phthiraptera), they are believed to have evolved from within the former order Psocoptera, which contained the bark lice and book lice, now found to be paraphyletic. They are often regarded as the most primitive of the hemipteroids. Psocodea contains around 11,000 species, divided among four suborders and more than 70 families. They range in size from 1–10 millimetres (0.04–0.4 in) in length.
Prionoglarididae is a family of the order Psocodea that are barklice characterized by the reduction or simplification of the lacinia in adults and the specialised form of the male genitalia. It contains the only known genus of animals, Neotrogla, where females possess a penis-like organ and take on typical male sex roles.
Trichadenotecnum is a genus of insects in the order Psocoptera, the booklice, barklice, and bookflies. It is one of the largest genera, including over 200 described species.
Lepidopsocidae are an insect family of bark lice belonging to the suborder Trogiomorpha. Colloquially, Lepidopsocidae are referred to as the Scaly-winged Barklice. There are more than 220 species described worldwide. Phylogenetic DNA analysis of relationships between families in Trogiomorpha propose that Lepidopsocidae is monophyletic, meaning that the taxa within all share a common ancestor. This is supported morphologically by the presence of scales and setae covering the body and forewings of Lepodopsocids. Sister families of Lepidoposcidae include Trogiidae and Psoquillidae.
Epipsocetae is an infraorder of psocids in the order Psocodea. There are about 5 families and more than 480 described species in Epipsocetae.
Ptyctini is a tribe of common barklice in the family Psocidae. There are about 6 genera and at least 20 described species in Ptyctini.
Psocinae is a subfamily of common barklice in the family Psocidae. There are about 11 genera and at least 40 described species in Psocinae.
Prionoglaris is a genus of large-winged psocids in the family Prionoglarididae, of which it is the type genus. There are four described species in Prionoglaris, found in Europe and the Middle East.
Afrotrogla is an African genus of large-winged psocids in the family Prionoglarididae, discovered and described by Charles Lienhard. There are three described species in Afrotrogla, all found in certain caves of Namibia.
