Coenraad Ritsema, also Cornelius Conrad Ritsema (13 April 1846,

Haarlem Haarlem (; predecessor of ''Harlem'' in English) is a city and municipality in the Netherlands. It is the capital of the province of North Holland. Haarlem is situated at the northern edge of the Randstad, one of the most populated metropoli ...

- 9 January 1929,

Wageningen Wageningen () is a municipality and a historic city in the central Netherlands, in the province of Gelderland. It is famous for Wageningen University, which specialises in life sciences. The municipality had a population of in , of which many t ...

) was a Dutch

entomologist Entomology () is the scientific study of insects, a branch of zoology. In the past the term "insect" was less specific, and historically the definition of entomology would also include the study of animals in other arthropod groups, such as arach ...

. Ritsema was a

Curator A curator (from la, cura, meaning "to take care") is a manager or overseer. When working with cultural organizations, a curator is typically a "collections curator" or an "exhibitions curator", and has multifaceted tasks dependent on the parti ...

at RMNH

Rijksmuseum van Natuurlijke Historie The Rijksmuseum van Natuurlijke Historie (National Museum of Natural History) was a museum on the Rapenburg in Leiden, the Netherlands. It was founded in 1820 by Royal Decree from a merger of several existing collections. This happened on the initi ...

(National Museum of Natural History) in Leiden from 1873 to 1916 and wrote many short papers describing new species of

Hymenoptera Hymenoptera is a large order (biology), order of insects, comprising the sawfly, sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are Par ...

and

Coleoptera Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...

. As part of his duties at the Leiden museum he worked in other fields for instance on

Decapoda The Decapoda or decapods (literally "ten-footed") are an order of crustaceans within the class Malacostraca, including many familiar groups, such as crabs, lobsters, crayfish, shrimp and prawns. Most decapods are scavengers. The order is esti ...

. He was a specialist on

Helotidae Helotidae is a family of beetles, in the suborder Polyphaga. The family includes about five extant genera, ''Helota'' MacLeay, ''Neohelota'' Ohta, ''Afrohelotina'' Kirejtshuk, ''Metahelotella'' Kirejtshuk, and ''Strophohelota'' Kirejtshuk. Hel ...

References

Bolton B, Alpert G, Ward PS, Naskrecki P. 2007. D-ROM''Bolton's Catalogue of the Ants of the World''. Harvard University Press. {{DEFAULTSORT:Ritsema, Coenraad 1846 births 1929 deaths Dutch entomologists Coleopterists Scientists from Haarlem