Kachinus is an extinct, monotypic

Monotypic

In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

, genus of ant-like stone beetle

Ant-like stone beetle

Scydmaenidae is a family of small beetles, commonly called ant-like stone beetles or scydmaenids. These beetles occur worldwide, and the family includes some 4,500 species in about 80 genera....

 in the family Staphylinidae containing the single species Kachinus antennatus.

The genus is known from only the holotype

Holotype

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...

, a single, complete adult, now deposited in the American Museum of Natural History

American Museum of Natural History

The American Museum of Natural History , located on the Upper West Side of Manhattan in New York City, United States, is one of the largest and most celebrated museums in the world...

 as specimen number "AMNH Bu-113". The amber

Amber

Amber is fossilized tree resin , which has been appreciated for its color and natural beauty since Neolithic times. Amber is used as an ingredient in perfumes, as a healing agent in folk medicine, and as jewelry. There are five classes of amber, defined on the basis of their chemical constituents...

 specimen is from deposits in Kachin, Tanai Village, 105 kilometres (65.2 mi) northwest of Myitkyna, Myanmar.

The holotype was first studied by Drs Stylianos Chatzimanolis of the University of Tennessee

University of Tennessee

The University of Tennessee is a public land-grant university headquartered at Knoxville, Tennessee, United States...

, 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...

 of the University of Kansas

University of Kansas

The University of Kansas is a public research university and the largest university in the state of Kansas. KU campuses are located in Lawrence, Wichita, Overland Park, and Kansas City, Kansas with the main campus being located in Lawrence on Mount Oread, the highest point in Lawrence. The...

, and Alfred Newton of the Field Museum. Chatzimanolis, Engel and Newton published the 2010 type description for K. antennatus in the journal Cretaceous Research

Cretaceous Research

Cretaceous Research is a bimonthly peer-reviewed scientific journal published by Elsevier. The journal focuses on topics dealing with the Cretaceous period and the K–T boundary.- Abstracting and indexing :...

, Volume 31. The genus name is a masculine derivation of the Kachin State

Kachin State

Kachin State , is the northernmost state of Burma. It is bordered by China to the north and east; Shan State to the south; and Sagaing Division and India to the west. It lies between north latitude 23° 27' and 28° 25' longitude 96° 0' and 98° 44'. The area of Kachin State is . The capital of the...

 in Northern Myanmar where the amber containing the type specimen was unearthed. The species name antennatus is 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...

, signifying "antenna

Antenna (biology)

Antennae in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes....

ed".

The beetle is small, only 0.6 millimetre (0.0236220472440945 in) long, possessing a light brown body with yellowish brown legs, antennae, and head. Kachinus has a unique combination of characters found in both the Cephennini and Eutheiini tribes of the Scydmaeninae supertribe Scydmaenitae. Elytra and pronotum which are not clearly discontinuous and a head which does not have a narrowed area from the vertex to the occiput are features found in the modern Cephennini genera. However the overall pronotum shape and body shape combined with shortened elytra are distinct features of Eutheiini. It is noted that with the distinctly elevated mesosternal keel Kachinus is similar in appearance to the modern genus Paraneseuthia.