ABSTRACT
Several species of Centris bees are known to occur sympatrically in many areas of the Costa Rican dry forest. In some areas, up to a dozen species of these solitary bees can be found together. The bees are considered one of the most important pollinator groups for a wide variety of plant species in the dry forest. Specialized glands in males for marking territories were found in 11 of the 12 Centris species. The glands were of two types: mandibular glands located in the head and tibial glands located in the hind leg. Most species possessed one type of well developed gland. Studies of nesting biology demonstrated that each Centris species had specific requirements. Differences in solitary or colonial behavior, habitat preferences, soil type, and nest architecture served to separate the six species in the two subgenera. For example,Centris adanae and Centris flavifrons build single-cell nests.
