Vol. 33, pp. 93-96 December 30, 1920 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



ANURAPHIS LONGICAUDA, A NEW APHID INJURI- 

 OUS TO PLUM TREES. 



BY A. C. BAKER. 



For several years past an undescribed species of Aphid has 

 occurred in injurious numbers upon the plum trees at Vienna, 

 Va. This species has also been found in Ashland, Neb., by 

 T. A. Williams and in House Springs, Mo., by H. Grubar. 

 It attacks both the twigs and the leaves and the twigs at- 

 tacked by the species are in nearly every case dead the follow- 

 ing year. Insects are found either upon the twigs or the 

 foliage throughout the summer and the apterous sexes are 

 met with upon the twigs where the eggs are laid in the fall. 

 While the spring forms are usually a dark brown, many of the 

 summer forms are pale yellowish white and these forms are 

 most often seen on the under sides of the leaves. 



Stem-mother. 1 



The stem-mothers hatch about the first of April. In 1916 some of 

 the young stem-mothers were noted on April 2nd while many of the eggs 

 had not yet hatched. On April 8th a heavy fall of snow occurred with 

 freezing weather and many of the stem-mothers were killed. They had 

 not advanced during this time past the first instar. 



Some of the remaining stem-mothers which were in the first instar on 

 April 7th were placed in sheltered experiments. These moulted first from 

 the 12th to the 14th. The other moults varied considerably but some 

 of the stem-mothers were adult and reproducing by April 24th. Others 

 were not reproducing until May 1st. 



Length, 1.68 mm.; width of abdomen, 1.2 mm. Antennae as follows: 

 Segment I, 0.048 mm, II, 0.048 mm., Ill, 0.336 mm., IV, 0.144 mm., V 



1 Type locality, Vienna, Va. Cotype slides in U. S. Nat. Mus. Coll. of Aphididae, 

 taken by the writer; Stem-mothers, April 17, 1913; alate forms, May 5, 1913; 

 apterous forms, May 15, 1913. 



20— Proc. Biol. Soc. Wash., Vol. 33, 1920. (93) 



