Sri Lanka Weevil or Exotic Weevil
Note: Yellow head, large eyes, thorax thinner than abdomen, spicules or spurs on the hind legs.
This tiny critter (about 1/4″ (6mm) long) is the adult stage of a Coleoptera: Curculionidae or a root feeding leaf notching weevil from the Indian subcontinent. This little beetle is commonly known as the Sri Lanka Weevil or Exotic Weevil, and by the scientific name Myllocerus undatus.
Identification
The Sri Lanka Weevil has an appearance similar to the native Little Leaf Notcher Weevil (Artipus floridanus), the major differences being Myllocerus undatus has a yellow head, much larger eyes, longer antennae, a thinner thorax and spiculs or spurs on the hind legs.
At about 1/4″ (6mm) long, Myllocerus may be difficult to the naked eye to identify properly without the aid of magnification.
Life Cycle
The adults lay eggs in soft organic matter on the ground under the host plant where the larvae burrow through the soil feeding on the roots of the host plant and pupate in the soil. The adults emerge from the soil to feed on a wide variety of host plants. The long and growing list is below…
Host Plants of Myllocerus undatus
a palm, Veitchia sp. (Palmae);
akee, Blighia sapida K. Koenig (Sapindaceae);
areca palm, Dypsis lutescens (H. Wendl.) Beentje & J. Dransf. (Palmae);
Australian brush-cherry, Syzygium paniculatum Gaertn. (Myrtaceae);
beeftree, Guapira discolor (Spreng.) Little (Nyctaginaceae);
black-olive, Bucida buceras L. (Combretaceae);
bottlebrush, Callistemon sp. (Myrtaceae);
Burmese fishtail palm, Caryota mitis Lour. (Palmae);
buttonwood, Conocarpus erectus L. (Combretaceae);
calamondin, Xcitrafortunella microcarpa (Rutaceae);
carrotwood, Cupaniopsis anacardiodes (A. Rich.) Radlk. (Anacardiaceae);
carambola, Averrhoa carambola (Oxalidaceae);
cashew, Anacardium occidentale L. (Anacardiaceae);
citrus, Citrus sp. (Rutaceae);
cocoplum, Chrysobalanus icaco L. (Chrysobalanaceae);
copper leaf plant, Acalypha wilkesiana (Euphorbiacea);
crepe myrtle, Lagerstroemia indica L. (Lythraceae);
dahoon holly, Ilex cassine L. (Aquifoliaceae);
earleaf acacia, Acacia auriculiformis A. Cunn ex Benth. (Leguminosae);
erythrina, Erythrina sp. (Leguminosae);
ficus, Ficus sp. (Moraceae);
Florida trema, Trema micranthum (L.) Blume (Ulmaceae);
glossy shower, Senna surattensis (Burm. f.) Irwin & Barneby (Leguminosae);
golden dewdrops, Duranta erecta L. (Verbenaceae);
grapefruit, Citrus x paradisi Macfad. (Rutaceae);
hackberry, Celtis laevigata Willd. (Ulmaceae);
hibiscus, Hibiscus rosa-sinensis L. (Malvaceae);
Hong Kong orchid tree, Bauhinia x blakeana S.T. Dunn (Leguminosae);
ice cream bean, Inga edulis (Leguminosae);
jaboticaba, Myrciaria cauliflora (DC.) O. Berg (Myrtaceae);
jambolan plum, Syzygium cuminii (L.) Skeels (Myrtaceae);
lantana, Lantana camara L. (Verbenaceae);
laurel oak, Quercus laurifolia Michx. (Fagaceae);
live oak, Quercus virginiana L. (Fagaceae);
longan, Dimocarpus longan Lour. (Sapindaceae);
loquat, Eriobotrya japonica Lindl. (Rosaceae);
lychee, Litchi sinensis Sonn. (Sapindaceae);
mahoe, Hibiscus tiliaceus L. (Malvaceae);
mahogany, Swietenia mahagoni (L.) Jacq. (Meliaceae);
mamey sapote, Pouteria sapota (Jacq.) H. E. Moore & Stearn (Sapotaceae);
mango, Mangifera indica L. (Anacardiaceae); muscadine,
Muscadine grape, Vitis rotundifolia Michx. (Vitaceae);
Rafflesia, Tetrastigma sp. (Vitaceae);
orange jasmine, Murraya paniculata (L.) Jack (Rutaceae);
orchid tree, Bauhinia sp. (Leguminosae);
oriental arborvitae, Platycladus orientalis (Cupressaceae);
passionflower, Passiflora sp. (Passifloraceae);
peach, Prunus persica (L.) Ratsch. (Rosaceae);
pigeon plum, Coccoloba diversifolia Jacq. (Polygonaceae);
plumbago, Plumbago auriculata Lam. (Plumbaginaceae);
pongam, Pongamia pinnata (L.) Pierre (Leguminosae);
powderpuff, Calliandra haematocephala Hassk. (Leguminosae);
pygmy date palm, Phoenix roebelenii O’Brien (Palmae);
Rafflesia, Tetrastigma sp. (Vitaceae);
red maple, Acer rubrum L. (Aceraceae);
red silk-cotton tree, Bombax ceiba L. (Bombacaceae);
rouge plant, Rivina humilis L. (Phytolaccaceae);
salt bush, Baccharis halimifolia L. (Compositae);
seagrape, Coccoloba uvifera (L.) L. (Polygonaceae);
shrubby false buttonweed, Spermacoce verticillata L. (Rubiaceae);
Spanish lime, Melicoccus bijugatus Jacq. (Sapindaceae);
spinach, Spinacia oleracea L. (Chenopodiaceae);
strangler fig, Ficus aurea L. (Moraceae);
Surinam cherry, Eugenia uniflora L. (Myrtaceae);
tropical almond, Terminalia catappa L. (Myrtaceae);
Turk’s cap, Malvaviscus penduliflorus DC. (Malvaceae);
upland cotton, Gossypium hirsutum L. (Malvaceae);
water chestnut, Pachira aquatica Aubl. (Bombacaceae);
white mulberry, Morus alba L. (Moraceae);
wild tamarind, Lysiloma latisiliquum Benth. (Leguminosae);
woman’s tongue, Albizia lebbeck (L.) Benth. (Leguminosae)
Control
No pesticides are listed for use on dooryard fruit trees for control of Myllocerus undatus.
Severe infestations on ornamental plants may be controlled with insecticides containing carbaryl (Sevin), acephate (Orthene, formerly Isotox), or pyrethroid insecticides labeled for use on leaf-feeding insects.
Myllocerus undatus is a weak flyer. When disturbed the weevil will run away, but when aggressively harassed it will flee by flying a short distance or drop to the ground and hide in grass, leaf litter or mulch under the plant it is infesting.
Sri Lanka Weevil eggs, larva, pupa, and adults have no natural enemies that are known of in Florida. Birds, anole or other lizards, and carnivorous insects do not seem to find them edible. I have been experimenting with beneficial nematodes to see if they offer any control by their feeding on the larvae growing in the ground, but to this point no relief has been noted in the control of this beetle.
Sources: Sri Lanka Weevil (Myllocerus undatus), University of Florida Extension service pamphlet, August 2006; Myllocerus undatus Marshall, a weevil new to the Western Hemisphere, Revised 19-Jan-2005, Florida Department of Agriculture & Consumer Services, Division of Plant Industry
