Alexander Ivanovitch Petrunkevitch (Russian: Александр Иванович Петранкевич, December 22, 1875 in Plysky near Kiev, now Ukraine – March 9, 1964 in New Haven) was an eminent Russian arachnologist of his time. From 1910 to 1939 he described over 130 spider species. One of his most famous essays was "The Spider and the Wasp." In it he uses effective word choices and some comic touch.
His aristocratic father, Ivan Illitch Petrunkevitch, was a liberal member of the First Duma and founded the Constitutional Democratic Party. After finishing his studies in Moscow and in Freiburg under August Weismann, Alexander settled in Yale in 1910, becoming a full professor in 1917. Apart from describing present-day species, he was a major figure in the study of fossil arachnids, including those in amber and from the Coal Measures. He also experimented with live specimens and worked on insects. He was elected to the National Academy of Science in 1954 and was also a member of the Connecticut Academy of Arts and Sciences. Throughout his career he remained politically active, trying to increase awareness of problems in Russia. He was also a skilled machinist and wrote two volumes of poetry (under the pseudonym Alexandr Jan-Ruban), and translated Pushkin into the English language, and Byron into Russian. He died in 1964.