Maladera matrida Argaman was first reported from Israel in the late 1970's and was subsequently described as a new species. Shortly thereafter, this species has become a serious pest of ornamental plants and agricultural crops. In this study we identified external anatomical features for distinguishing between the three larval instars and between the two sexes of pupae and adults collected in the field. Larval instars may be divided as follows: first instar, head width less than 1.8 mm; second

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... nstar, head width above 1.9 mm and ratio of body length to head width below 3; and third instar, body length above 9 mm. Male pupae may easily be recognized by an ampulla covering the developing genitalia on the posteroventral abdominal segments. Males usually had longer antennal laminae (mean = 823 |iin, range 750-900 |im) than females (mean = 704 |J.m, range of 570-790 (xm); however, in about 10% of the beetles this length overlapped between the sexes (range 750-790 |i.m).