Estimating the body size of orchid bees (Hymenoptera: Apidae: Euglossini) using the distance between their tegulae

Abstract

Body mass is an important morphological trait, which is associated with the physiology and ecology of insects. In the past, estimates of body mass were often based on general mathematical equations in which body mass was related to linear measurements of anatomical structures. For example, in female bees, estimates of dry body mass are expected to follow a non-linear relationship (power function) with the distance between the tegulae on their thorax, also known as the intertegular distance (ITD). Nonetheless, a major group of bees not included in previous studies are the Neotropical orchid bees of which mostly males are collected. We investigated whether a similar non-linear relationship is also the case for male orchid bees and we found positive evidence as the relationship can be represented by a power function providing reliable estimate of dry body mass. This is particularly important for estimating dry body mass of individuals stored in collections.

Keywords

• apoidea
• morphology
• biometrics
• dry body mass
• museum collection
• power function