Sphecomyrma is an extinct genus of ants which existed in the Cretaceous approximately 79 to 92 million years ago. The first specimens were collected in 1966, found embedded in amber which had been exposed in the cliffs of Cliffwood, New Jersey, by Edmund Frey and his wife. In 1967, zoologists E. O. Wilson, Frank Carpenter and William L. Brown, Jr. published a paper describing and naming Sphecomyrma freyi. They described an ant with a mosaic of features—a mix of characteristics from modern ants and aculeate wasps. It possessed a metapleural gland, a feature unique to ants. Furthermore, it was wingless and had a petiole which was ant-like in form. The mandibles were short and wasp-like with only two teeth, the gaster was constricted, and the middle and hind legs had double tibial spurs. The antennae were, in form, midway between the wasps and ants, having a short first segment but a long flexible funiculus. Two additional species, S. canadensis and S. mesaki, were described in 1985 and 2005, respectively.
Electroatopos castaneus is an extinct species of ant-like stone beetle, described in 2010, and the only species in the genus Electroatopos. It existed in what is now Myanmar during the Middle Cretaceous period.
Kachinus is an extinct genus of ant-like stone beetle in the family Staphylinidae containing the single species Kachinus antennatus.
Plumalexius is a genus of wasps in the extinct monotypic family Plumalexiidae, containing two species: the type species Plumalexius rasnitsyni, known from the Late Cretaceous White Oaks Pit in Sayreville, New Jersey, and Plumalexius ohmkuhnlei, known from the Cretaceous Burmese amber.
Diochus electrus is an extinct species of rove beetle in genus Diochus, the only definitive fossil species in subfamily Staphylininae. The species is known only from the middle Eocene, Lutetian stage Baltic amber found in the Blaue Erde deposits, Baltic region, Northern Europe.
Prosolierius is an extinct genus of rove beetle which existed in what is now Lebanon, Myanmar and Spain during the Barremian through the Albian period. It was described by Margaret K. Thayer, Alfred F. Newton and Stylianos Chatzimanolis in 2012.
Astreptolabis is an extinct genus of earwig in the Dermaptera family Pygidicranidae known from a group of Cretaceous fossils found in Myanmar. The genus contains two described species, Astreptolabis ethirosomatia and Astreptolabis laevis and is the sole member of the subfamily Astreptolabidinae.
Tytthodiplatys is an extinct genus of earwig in the family Diplatyidae known from a Cretaceous fossil found in Myanmar. The genus contains a single described species, Tytthodiplatys mecynocercus.
Brownimecia is an extinct genus of ants, the only genus in the tribe Brownimeciini and subfamily Brownimeciinae of the Formicidae. Fossils of the single identified species, Brownimecia clavata, are known from the Middle Cretaceous of North America. The genus is one of several ants described from Middle Cretaceous ambers of New Jersey. Brownimecia was initially placed in the subfamily Ponerinae, until it was transferred to its own subfamily in 2003; it can be distinguished from other ants due to its unusual sickle-like mandibles and other morphological features that makes this ant unique among the Formicidae. The ant is also small, measuring 3.43 millimetres (0.135 in), and a stinger is present in almost all of the specimens collected. The morphology of the mandibles suggest a high level of feeding specialization.
Haidoterminus is an extinct genus of ant in the Formicidae subfamily Haidomyrmecinae, and is one of only nine genera placed in this subfamily. The genus contains a single described species Haidoterminus cippus and is known from one Late Cretaceous fossil which has been found in North America.
Haidomyrmex is an extinct genus of ants in the formicid subfamily Haidomyrmecinae, and is one of nine genera placed in the subfamily Haidomyrmecinae. The genus contains three described species Haidomyrmex cerberus, Haidomyrmex scimitarus, and Haidomyrmex zigrasi. All three are known from single Late Cretaceous fossils which have been found in Asia. H. cerberus is the type species and Haidomyrmex the type genus for the subfamily Haidomyrmecinae.
Burmomyrma is an extinct genus of aculeate hymenopteran, suggested to be an ant. The genus contains a single described species, Burmomyrma rossi. Burmomyrma is known from a single Middle Cretaceous fossil which was found in Asia.
Zigrasolabis is an extinct genus of earwig in the family Labiduridae known from Cretaceous fossils found in Myanmar. The genus contains a single described species, Zigrasolabis speciosa.
Toxolabis is an extinct genus of earwig in the dermapteran family Anisolabididae known from a Cretaceous fossil found in Burma. The genus contains a single described species, Toxolabis zigrasi.
Myanmyrma is an extinct genus of ants not placed into any Formicidae subfamily. Fossils of the single known species, Myanmyrma gracilis, are known from the Middle Cretaceous of Asia. The genus is one of several ants described from Middle Cretaceous ambers of Myanmar.
Cananeuretus is an extinct genus of ant in the Formicidae subfamily Aneuretinae, and is one of two Cretaceous genera of the subfamily. The genus contains a single described species Cananeuretus occidentalis and is known from one Late Cretaceous fossil which has been found in North America.
Gerontoformica is an extinct genus of stem-group ants. The genus contains thirteen described species known from Late Cretaceous fossils found in Asia and Europe. The species were described between 2004 and 2016, with a number of the species formerly being placed into the junior synonym genus Sphecomyrmodes.
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.
Ceratomyrmex is an extinct genus of ant in the Formicidae subfamily Haidomyrmecinae. The genus contains a single described species Ceratomyrmex ellenbergeri and is known from several Late Cretaceous fossils which have been found in Asia.
New Jersey Amber, sometimes called Raritan amber, is amber found in the Raritan and Magothy Formations of the Central Atlantic (Eastern) coast of the United States. It is dated to the Late Cretaceous, Turonian age, based on pollen analysis of the host formations. It has been known since the 19th century, with several of the old clay-pit sites now producing many specimens for study. It has yielded a number of organism fossils, including fungi, plants, tardigrades, insects and feathers. The first identified Cretaceous age ant was described from a fossil found in New Jersey in 1966.
