10 WHITE FLIES INJURIOUS TO CITRUS IX FLORIDA. 
SPECIES OF WHITE FLIES AFFECTING CITRUS. 
Twelve species and one subspecies of the family Aleyrodidse are 
known to breed upon citrus. The list of these insects, the authority 
for the original description, the recorded distribution, and the food- 
plant records are given in Table I : 
Table I. — Aleyrodidse that breed upon citrus. 
Species. 
Described by- 
Occurrence. 
Food plants other than 
citrus. 
Aleyrodes citri (syn. 
rantii). 1 
Aleyrodes floccosa 
Aleyrodes floridensis. 
Aleyrodes giffardi . 
Aleyrodes howardi 
Aleyrodes marlatti 
Aleyrodes mori 
Aleyrodes mori arizonensis 
Aleyrodes nubifera 
Aleyrodes spinifera 
Aleyrodes struthanthi . 
Aleyrodes vitrinellus 2 
Paraleyrodes persese. . 
Riley and 
ard. 
Maskell.... 
Quaintance . 
How- 
Kotinsky... 
Quaintance. 
....do... 
do... 
Cocker ell. 
Berger... 
Quaintance . 
Hempel 
Cockerell — 
Quaintance. 
North and South America, 
Asia, Japan. 
Mexico, Jamaica 
United States ( Florida) 
Hawaii 
Cuba, United States (Flor- 
ida). 
Japan 
United States (Florida)... 
United States (Arizona) . . . 
United States (Florida, 
Louisiana), Cuba. 
Java 
Brazil 
Mexico 
United States (Florida).... 
See list, p. 29. 
Guaiacum officinale. 
Persea gratissima (alligator 
pear), Psidium guajava 
(guava). 
None recorded. 
Do. 
Do. 
Mulberry, sweet gum, etc. 
None recorded. 
Ficus nitida. 
Rosa spp. 
Michelia flava, Loranthus 
(struthansus) flexicaulis. 
None recorded. 
Do. 
1 Mr. A. L. Quaintance, after careful comparison of material from Maskell's collection, evidently type 
material, with A . citri, concluded that Maskell's aurantii was the same as Riley and Howard's citri. Through 
the kindness of Mr. Quaintance the authors have had an opportunity to examine the material referred to 
and agree with him in considering aurantii a synonym of citri. 
2 There seems to be some doubt as to the idehtity'of the food plant of this species, for in connection with 
the description the authority for it gives the following food plant record: " On the under side of leaves which 
appear to be those of orange." 
Of the Aleyrodidse referred to above, A. citri, A. giffardi, A. howardi 
(PL II, figs. 2, 4), and A. nubifera are known to be orange pests or 
capable of becoming orange pests. A. floridensis, A. mori (PL II, 
fig. 1), A. mori arizonensis, and Paraleyrodes persese (PL II, fi.g. 3) 
apparently -are not likely to cause injury to citrus, while the remainder 
of those listed are doubtful in this respect. 
Paraleyrodes persese is found in all sections of Florida and is fre- 
quently quite abundant, but in only one instance has it been known 
to cause blackening of the foliage of citrus trees. This was in the 
winter of 1906-7 and occurred in a pinery where in one section citrus 
nursery trees were being grown. In the course of two or three months 
after being first noticed the insects were reduced to the point of 
scarcity through parasitism by a new species of Encarsia, winch 
Dr. L. O. Howard has described under the name of Encarsia variegata. 
Observations extending over three years indicate that this parasite 
will effectively control P. persese and that it is unlikely that tins 
aleyrodid will ever cause noticeable injury under ordinary conditions. 
It is, however, possible that the appearance of a prolific hyperparasite 
of Encarsia variegata might seriously interfere with the present equi- 
librium hi nature. 
