Autothysis or suicidal altruism is the process where an animal destroys itself via an internal rupturing or explosion of an organ which ruptures the skin. The term was proposed by Ulrich Maschwitz and Eleonore Maschwitz in 1974 to describe the defensive mechanism of Colobopsis saundersi, a species of ant. It is caused by a contraction of muscles around a large gland that leads to the breaking of the gland wall. Some termites release a sticky secretion by rupturing a gland near the skin of their neck, producing a tar effect in defense against ants.
![<i>Colobopsis saundersi</i> Ant species capable of suicidal altruism](https://upload.wikimedia.org/wikipedia/commons/thumb/8/85/Camponotus_saundersi_casent0179025_profile_1.jpg/320px-Camponotus_saundersi_casent0179025_profile_1.jpg)
Colobopsis saundersi, also called the Malaysian exploding ant, is a species of ant found in Malaysia and Brunei, belonging to the genus Colobopsis. A worker can explode suicidally and aggressively as an ultimate act of defense, an ability it has in common with several other species in this genus and a few other insects. The ant has an enormously enlarged mandibular gland, many times the size of other ants, which produces adhesive secretions for defense. According to a 2018 study, this species forms a species complex and is probably related to C. explodens, which is part of the C. cylindrica group.
![<i>Acaenasuchus</i> Genus of reptiles](https://upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Acaenasuchus.png/320px-Acaenasuchus.png)
Acaenasuchus is an extinct genus of pseudosuchian, endemic to what would be presently be known as Arizona during the Late Triassic, specifically during the Carnian and Norian stages of the Triassic. Acaenasuchus had a stratigraphic range of approximately 11.5 million years. Acaenasuchus is further categorized as one of the type fauna that belong to the Adamanian LVF, based on the fauna of the Blue Mesa Member of the Chinle Petrified Forest Formation of Arizona, where Acaenasuchus was initially discovered.
![<i>Globitermes sulphureus</i> Species of Asian termite whose soldiers are known for their potentially suicidal attack.](https://upload.wikimedia.org/wikipedia/commons/thumb/d/dc/Globitermes_sulphureus.jpg/320px-Globitermes_sulphureus.jpg)
Globitermes sulphureus is a species of termite that is very common in central and southern Vietnam and also present in other areas of South East Asia, including Cambodia, Thailand, and Peninsular Malaysia. They live in nests made of earth that can be up to 1.5 m tall and can contain tens of thousands of individuals. Between five and 10 per cent of the population are soldier termites which can be recognised by their yellow abdomen and two large, curved mandibles. The termites use autothysis as a defense mechanism.
![<i>Diaphoromyrma</i> Genus of ants](https://upload.wikimedia.org/wikipedia/commons/thumb/8/87/CASENT0178237_Diaphoromyrma_sofiae.jpg/320px-CASENT0178237_Diaphoromyrma_sofiae.jpg)
Diaphoromyrma is a genus of ants in the subfamily Myrmicinae. It contains the single species Diaphoromyrma sofiae, known only from workers from the type locality in Bahia, Brazil. The genus is apparently close to Allomerus and Diplomorium in the Solenopsidini, but its tribal attribution remains uncertain.
![<i>Fodonyx</i> Extinct genus of reptiles](https://upload.wikimedia.org/wikipedia/commons/thumb/4/47/Fodonyx_NT.jpg/320px-Fodonyx_NT.jpg)
Fodonyx is an extinct genus of rhynchosaur from the middle Triassic epoch of Devon in England. Its fossils were discovered in Otter Sandstone Formation and were first assigned to Rhynchosaurus spenceri. This species was reassigned to its own genus, Fodonyx the holotype of which is EXEMS 60/1985/292, that described by David W. E. Hone and Michael J. Benton in 2008. In 2010, one skull was reassigned to the new genus Bentonyx. It is distinguished from other rhynchosaurs by a single autapomorphy, the ventral angling of the paraoccipital processes. In all other rhynchosaurs these processes angle dorsally or are horizontal. It is not known if this conferred any advantage to Fodonyx. Fodonyx was between 40 and 50 cm long.
![<i>Cephalotes dieteri</i> Extinct species of ant](https://upload.wikimedia.org/wikipedia/commons/thumb/a/a2/Cephalotes_dieteri_SMNSDO4162_profile.jpg/320px-Cephalotes_dieteri_SMNSDO4162_profile.jpg)
Cephalotes dieteri is an extinct species of ant in the subfamily Myrmicinae known from two Middle Miocene fossils found in amber on Hispaniola. At the time of description, C. dieteri was one of seven fossil ant species placed in the Cephalotescoffeae clade.
![<i>Cephalotes hispaniolicus</i> Extinct species of ant](https://upload.wikimedia.org/wikipedia/commons/thumb/c/ca/Cephalotes_hispaniolicus_SMNSDO4163_dorsal.jpg/320px-Cephalotes_hispaniolicus_SMNSDO4163_dorsal.jpg)
Cephalotes hispaniolicus is an extinct species of ant in the subfamily Myrmicinae known from a single Middle Miocene fossil found in amber on Hispaniola. At the time of description C. hispaniolicus was one of six ant species placed in the Cephalotesmultispinosus clade.
![<i>Polyrhachis</i> Genus of ants](https://upload.wikimedia.org/wikipedia/commons/thumb/2/22/PolyrhachisGracilior2.jpg/320px-PolyrhachisGracilior2.jpg)
Polyrhachis is a genus of formicine ants found in the Old World with over 600 species. The genus is yet to be comprehensively resolved and contains many varied species including nest-weavers, swimming workers, soil and tree-dwellers. First fossil record of this genus was P. annosa from Miocene.
![<i>Apterostigma</i> Genus of ants](https://upload.wikimedia.org/wikipedia/commons/thumb/9/90/Apterostigma_pilosum_casent0173821_profile_1.jpg/320px-Apterostigma_pilosum_casent0173821_profile_1.jpg)
Apterostigma is a genus of New World ants of the subfamily Myrmicinae. Two species have been described from fossils preserved in Dominican amber, while the others are extant. They are fungus-growing ants, though, unlike the majority of other species in Attini who grow Lepiotaceae, some species have begun cultivating Tricholomataceae.
![<i>Tatuidris</i> Genus of ants](https://upload.wikimedia.org/wikipedia/commons/thumb/7/71/Tatuidris_tatusia_psw7891-9_profile_1.jpg/320px-Tatuidris_tatusia_psw7891-9_profile_1.jpg)
Tatuidris, or armadillo ant, is a rare genus of ants consisting of a single species, Tatuidris tatusia. The ants are small in size and inhabit the leaf litter of Neotropical forests in Central and South America, from Mexico to Brazil. Workers are ferruginous-colored to dark red and present a distinctive morphology, consisting of a shield-like head with a broad vertex, ventrally-turned heavy mandibles which do not overlap at full closure, and unique among ants – an antenna socket apparatus sitting upside-down. Little is known about the biology of the ants, but they are likely nocturnal and specialist predators.
![<i>Daceton armigerum</i> Species of ant](https://upload.wikimedia.org/wikipedia/commons/thumb/8/81/Daceton_armigerum_casent0178489_dorsal_1.jpg/320px-Daceton_armigerum_casent0178489_dorsal_1.jpg)
Daceton armigerum is a Neotropical species of arboreal ants, distributed throughout northern South America. D. armigerum combines several traits generally noted in some other arboreal ants i.e., populous colonies, large and/or polydomous nests, intra- and interspecific aggressiveness, trophobiosis, and capturing prey by spread-eagling them.
![<i>Zigrasimecia</i> Extinct genus of ants](https://upload.wikimedia.org/wikipedia/commons/thumb/9/9c/Zigrasimecia_hoelldobleri_FANTWEB00052_right_profile.jpg/320px-Zigrasimecia_hoelldobleri_FANTWEB00052_right_profile.jpg)
Zigrasimecia is an extinct genus of ants which existed in the Cretaceous period approximately 98 million years ago. The first specimens were collected from Burmese amber in Kachin State, 100 kilometres (62 mi) west of Myitkyina town in Myanmar. In 2013, palaeoentomologists Phillip Barden and David Grimaldi published a paper describing and naming Zigrasimecia tonsora. They described a dealate female with unusual features, notably the highly specialized mandibles. Other features include large ocelli, short scapes, 12 antennomeres, small eyes, and a clypeal margin that has a row of peg-like denticles. The genus Zigrasimecia was originally incertae sedis within Formicidae until a second species, Zigrasimecia ferox, was described in 2014, leading to its placement in the subfamily Sphecomyrminae. Later, it was considered to belong to the distinct subfamily Zigrasimeciinae.
![<i>Sphinctomyrmex stali</i> Species of ant](https://upload.wikimedia.org/wikipedia/commons/thumb/c/cc/Sphinctomyrmex_stali_casent0178866_profile_1.jpg/320px-Sphinctomyrmex_stali_casent0178866_profile_1.jpg)
Sphinctomyrmex stali is a Neotropical species of ants in the subfamily Dorylinae. Mayr described the genus Sphinctomyrmex with S. stali as its type species, based on a single dealate gyne. However, except for the holotype, there are no records of normal (alate) gynes for S. stali. All reproductive females collected after the original description are ergatoids.
Kempfidris is a Neotropical genus of ants in the subfamily Myrmicinae containing the single species Kempfidris inusualis. Known from Brazil, Ecuador and Venezuela, the species was originally described as Monomorium inusuale in 2007, but was reclassified as the type species for the new genus Kempfidris in 2014. The species is only known from workers and almost nothing is known about their natural history.
Pristomyrmex tsujii is a species of ant in the genus Pristomyrmex. Known from Fiji, where they are widely distributed but rarely encountered. The species has a discrete ergatoid queen caste that is intermediate between a worker and an alate queen.
![<i>Camelomecia</i> Extinct genus of ants](https://upload.wikimedia.org/wikipedia/commons/thumb/5/56/Camelomecia_janovitzi_AMNH-BUTJ003_right_profile.jpg/320px-Camelomecia_janovitzi_AMNH-BUTJ003_right_profile.jpg)
Camelomecia is an extinct genus of stem-group ants not placed into any Formicidae subfamily. Fossils of the single known species, Camelomecia janovitzi, are known from the Middle Cretaceous of Asia. The genus is one of several ants described from Middle Cretaceous ambers of Myanmar.
![<i>Bradoponera</i> Extinct genus of ants](https://upload.wikimedia.org/wikipedia/commons/thumb/9/97/Bradoponera_meieri_MBIGK177_profile.jpg/320px-Bradoponera_meieri_MBIGK177_profile.jpg)
Bradoponera is an extinct genus of ant in the Formicidae subfamily Proceratiinae, and is one of four genera of the subfamily. The genus contains four described species Bradoponera electrina, Bradoponera meieri, Bradoponera similis, and Bradoponera wunderlichi. The species are known from several Middle Eocene amber fossils which were found in Europe.
![<i>Colobopsis</i> Genus of ant](https://upload.wikimedia.org/wikipedia/commons/thumb/6/63/Colobopsis_truncata_casent0179881_p_1_high.jpg/320px-Colobopsis_truncata_casent0179881_p_1_high.jpg)
Colobopsis is a genus of ant in the subfamily Formicinae. This genus was first described in 1861 by Mayr and contains 95 species. The type species is Colobopsis truncata.