250 



THE AGRICULTURAL NEWS. 



August 9, 1919 



INSECT NOTES. 



NOTES ON SOME INSECT PESTS IN 

 COSTA RICA 



The notes which appear below are copied from the 

 Journal of Economic En/o?nolo'::y for June 1919 (Vol. 12, 

 p. 269). They are by Mr. James Zetek. Entomologist, 

 Ancon, C*nal Zone, anl they give an account of porae 

 observations mide while on a visit to Costa Kica. during 

 February and March of this yeir of Rome of th'! inse:t 

 pests of that country. 



The three insects mentioned are of interest to the 

 West Indian readers of the Agricultural Nc-,t'S. 



The purple scale {Lcpidosaphes bcckii) is a pest of long 

 standing of all citrus plants throughout the West Indies ; 

 the spiny citru.s white fly (Akurocanfhus woglumi) has 

 recently attracted attention by its attacks on citrus in 

 Cuba, Jamaica, and the Bahamas (see Agricultural Ale7VS, 

 Vol. XVI, pp 10 and 282 1; the Hawaiian sugar-cane 

 borer (RliaMociiemis obscurus) while abundant throughout 

 the sugar-producing localities in the Pacific is not known 

 to occur in the West Indies or in Central America, although 

 Dr. W, D. Pierce in the 'Manuil of Dangerous Insects, 

 likely to be introduced into the Unit'd States through 

 importations', gives West Indian localities in the distiibu- 

 tion of this pest. The inclusion of these loolities would 

 •appear to be an error (see review in this Journal, Vol. XVII, 

 p. 391). 



Formerly, the genus Sphenopliorus was made to in- 

 clude the West Indian weevil borers of the sugar-cane, 

 {Metamasius sericeus and J/. liemipteri/.s), the black weevil 

 borer of the banana (Cosmopolites sordidus) and the 

 Hawaiian sugar-cane borer ( Rhahdocnemis obscurus), but 

 the last mentioned species has always been considered to 

 belong definitely to the Pacific regions, and not to the 

 Caribbean or Atlantic localities. 



These insects are all .similar in habit. They generally 

 attack dying or decaying plant tissue, although nbscurus 

 i» said to be a serious p"st of healthy sugar can", and 

 they all seem to have much the same range of food-plants. 

 The 81 ecies sordidus is recorded as a pest of banana (see 

 Agricultural Nc7t<s, Vo". XVI, pp. 298 and .'517) ; all the 

 others are recorded as pests of sugarcane, but they attack 

 bananas ; the species obscurus attacks, in addition to 

 sngar-cane and banana, the coco nut and other palms, and 

 the papaw, while the species sericeus has been foun I attack- 

 ing the decaying 'may pole' or flower stalk of a large agave. 



Tt'e accompanying illustrations (Figs. 1 and 2) will serve 

 to give an idea of these insects. The species seric-'us and 

 hemipttrus are similar in colouring, being brown, with dark- 

 er markings, while obscurus and sordidus are uniformly 

 dark, almost or quite black. 



'The most important "find" was, no doubt, the "mo?ca 

 prieta", or spiny citrus white fly (Alcurncunllius woglumi 

 Asbby). It was very abundant on citrus of various species a 



Limon, and at all the stations of the Northern Railroad as 

 far as Peralta. At Cartago, at an elevation about 1 mile, 

 it was not found. The degree of infestation was worse than 

 it is in the Canal Zone. The trees were so heavily infested 

 as to be readily noticeable from the car windows. This 

 white fly occurs probably all ihro.igh Central America and 

 tropical South America, particularly along the Atlantic sea- 

 board. From c|ue3tions asked of the customs and port 

 authorities, and from actual observations, it would appear 

 that this insect gainel access to Costa Rica from small 

 sailine vessels coming from Sin Andres and other islands of 

 the Caribbean. It seems to be an inborn custom of tha 

 islanders to carry potted plants wherever they go. Thus 

 far Hfty-two hosts, representing twenty-gix families of plants, 

 have been recorded for A. woglumi, among them being the 

 various species of citrqs, manao, star-apple, eishew apple 

 (raaranon), papaya, cherimiya, maraei, plantain, and coffee. 

 'The purple scale, {Lipidos'phes beck'ii Newm. \ and 

 sooty mould were extremely abundant on both leaver and 

 fruit of citrus 



kS. 



Fiii. 1. Weevil Boeer ok Fic 2. Weevil Borer ok 



THE SUGAR-C.^NE AdULT THE SuUAR-C.VNE liRUB. 



'Another bad pest was ihe Hawaiian sugarcane bor r, 

 {Rhabdocnemis obscurus, Bois.) It was exceedingly abundant 

 at Zent, C. P.. in banana stumps an I cuttings. As many as 

 forty adults were taken out of a smill piece of stalk about a 

 foot long. Dr. \V. U. Pierce, in his 'Manual of Dangerous 

 Insects', cites the following hosts for this sveevil- banana, 

 sugar-cane, coco-nut, sagopalm, royal palm, wine palm and 

 papyrus. 



'The important observation here was, a few adjits wore 

 found crawling on the leaves of the banana, showing that this 

 .serious pest can very easily be introdui-od into the Uniteil 

 States among the banana leaves used as packing for fruit un 

 boats calling at Xew Orleans. At Limon, and awaiting boats 

 for shipment to the United Sta'es. were about a hundred Hat 

 cars loaded with Balsa logs, and, from data obtaiiieil, these 

 were here from one to four weeks. Urider the bark of these 

 logs were found a numbsr of le|)idopterou3 larvae aud pipie. 

 The great majority of the logs were infested with several 

 species of borers, specimens of which have been sent to the 

 Bureau of Kntoinology for iilentilication. These borers 

 were very active and abundant. As th" determinations are 

 lacking at present writing, it is impossible tosiy whether 

 they are alrea ly present in the United States However, the 

 degree of infeitation, and the eas(! with which such lug-i can 

 enter the United Slates, make tlie introduction of such p sts 

 a certainty, and it is time to pay attention to the possibilities 

 of this source of danger. Otherwise many new and dangerou.s 

 pests will unquestionably be added to our already large list 

 of insect-immigrants.' 



