I've asked before but the molt was fresh and the picture was not amazing. i'm hoping this picture is better. Murphy is easily 4" L.S. now. I have noticed patch on his abdomen is now black. It used to be gold. This makes me believe she is an acteon. I'd love help from you pro's ! T.Y.
@03ISA Are you talking about the mirror patch of urticating hair? Urticating setae have different properties than the setae covering the rest of their bodies - it only looks gold because of the way that the light reflects off it. So, that patch can look different in different lighting scenarios and at different angles.
This is the exact same tarantula and the photos were taken only moments apart. Both were taken using flash, but at different angles. The urticating hair patch looks darker in the second one, but it is only the angle the photo was taken at.
@03ISA The best way to determine the species is to check the spermathecae, but it seems that these two species have very similar structure. Eventually, actaeon lose the red abdomen setae, while the abdomen on iheringi remains bright red all their lives.
@VanessaS The shape of the spermathecae in Grammostola is typically a generic character so it isn't useful for identifying the majority of the species in the genus.
However, in G. actaeon and G. iheringi, the spermathecae is very different in shape according to Schiapelli and Gerschman de Pikelin (1962). G. iheringi has receptacles that curve inward where in G. actaeon the receptacles are straight which is typical for the genus.
Due to copyright rules, I can not post the pictures from the research paper, but I included the reference in case you want to download it from the World Spider Catalog and look for yourself. Unfortunately, I can not find a single picture of the spermatheca from an adult female of either species that people are buying to confirm if the shape of the spermatheca matches the drawings in the Schiapelli and Gerschman de Pikelin paper. It would be interesting to know if any of the tarantulas sold as G. iheringi or G. actaeon have the curved spermathecal receptacles.
Schiapelli, R. D. & Gerschman de P., B. S. (1962a). Estudio de seis mudas de un ejemplar f del género Grammostola Simon, 1892 (Araneae: Theraphosidae). Physis, Revista de la Sociedad Argentina de Ciencias Naturales (C) 23: 11-13.
@AphonopelmaTX I thought that there was some controversy over whether the hobby iheringi is what was described as iheringi originally. That is why I don't always refer back to the WSC and check what other hobbyists are posting for some species instead. Unfortunately, those photos often don't provide enough detail and my photos of the two don't either.
Maybe when my two girls are large enough, I will be able to get decent photos to compare to the paper.
Thank you both! Crazy to think with all the intelligent people out there studying tarantulas there are no 2 good pictures to compare already. Murphy just molted but it was before I got my new macro lense so the pictures are far less than ideal. When she molts again I will search the references you provided. Thank you both for your time and the education your providing me.