Ceratina of Eastern Canada 



JESO Volume 139, 2008 



FIGURE 1 . SEM images of female Ceratina thoraces. a. C. dupla, more punctate with two 

 or more complete longitudinal rows of punctures inside the parapsidal lines and around the 

 medial line. Arrow indicates the medial line (M). b. C. calcarata, less punctate with one to 

 two incomplete longitudinal rows of punctures inside the parapsidal lines and around the 

 medial line. Arrow indicates the parapsidal line (P). 



SEM images were obtained using an AMRAY 1600 Turbo scanning electron 

 microscope. Specimens were mounted onto a carbon adhesive tab and silver paint was 

 applied to the specimen edges to aid in sample conductivity. Using secondary electron 

 scintillation detector and 15kV accelerating voltage, images were processed using ORION 

 Digital Image grabbing software (version 6.51). SEM images were used to confirm the 

 validity and consistency of the revised morphological character developed to distinguish 

 between female C. calcarata and C. dupla. SEM images and type specimens have been 

 retained in the collection of M.H. Richards at Brock University. 



Taxonomy Test for Non-Taxonomists 



Since Mitchell's (1962) key is sufficient to identify male C. calcarata versus C. 

 dupla and C. strenua of both sexes these characters were not altered from the original key 

 descriptions. However, due to the difficulty distinguishing female C. calcarata versus C. 

 dupla a new character was developed to differentiate females of the two species. Following 

 scanning electron microscopy, SEM photographs of female C. calcarata and C. dupla were 

 given to 24 naive non-entomologists along with 15 pinned specimens of C. calcarata and 13 

 pinned C. dupla. Bees were randomly labeled from 1 to 28 and placed in a box. Identifiers 

 were given the box and a dissecting microscope and shown where on the bee the scutum 

 was located (most volunteers had never seen a bee under a microscope before). Identifiers 

 then assigned each specimen to either C. calcarata or C. dupla using figures 1 and 5, as 

 well as by reference to a written description of the character (key to females, couplet 2). 

 Identifiers were later graded against the original identifications by the senior author. 



DNA Sequence Analysis 



Total genomic DNA was isolated from the head and abdominal segments of 

 the 24 SEM specimens, using the Sigma-Aldrich GenElute Mammalian Genomic DNA 



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