Karl Rost was a German

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 entomologist  and insect dealer.
From 1886 Rost was an insect dealer (Insekten-Händler) and professional insect collector in Berlin

Berlin

Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...

. He collected insects later offered for sale in Spain

Spain

Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

  and Greece

Greece

Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

 (annually 1887-1898). In 1899 he went on an expedition to Siberia

Siberia

Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...

  and in 1900 -1901 collected in the Caucasus

Caucasus

The Caucasus, also Caucas or Caucasia , is a geopolitical region at the border of Europe and Asia, and situated between the Black and the Caspian sea...

. In 1903 he went to Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 to collect insects for the herbarium dealer George Meyer Darcis (He went to Japan again in 1911) after two years in North-West India (1906 for Meyer-Darcis and 1907 for his dealership). Rost described many new species from these regions.
Parts of his personal collection are in the Museum für Naturkunde in Berlin and other parts are in the Zoologisch Museum Amsterdam. The rest were privately sold, many to the dealership Staudinger

Otto Staudinger

Otto Staudinger was a German entomologist and a natural history dealer considered one of the largest in the world specialising in the collection and sale of insects to museums, scientific institutions, and individuals....

 - Bang-Haas

Andreas Bang-Haas

Andreas Bang-Haas was a Danish entomologist and insect dealer.In 1879 he entered into the business of the insect dealer Otto Staudinger.He married Staudinger's daughter in 1880 and became co-owner of the firm, now "Staudinger & Bang-Haas", in 1884 or 1887.The business was eventually taken over by...

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