 Although there are a few lookalike species with similar overall appearance , in the field , Gyroporus cyanescens is typically readily recognized by its characteristic straw @-@ yellow color and nearly instantaneous dark blue bruising . G. <unk> is smaller , with a dull brownish @-@ yellow cap . Although its flesh has a bluing reaction to injury , its yellow pore surface does not . It has larger spores , measuring 9 – 15 by 5 – 7 µm . G. <unk> , found along the Gulf Coast of the United States , is similar in appearance , but lacks the bluing reaction . Newly described from China in 2003 , G. <unk> closely resembles G. cyanescens , and was frequently confused with that species . It has a smaller fruit body , with a brownish cap up to 8 cm ( 3 @.@ 1 in ) in diameter . Its staining reaction involves a change from light turquoise to dark turquoise or dark blue . Its spores are 5 – 8 @.@ 5 by 4 – 5 @.@ 3 µm . Suillus tomentosus has brownish pores that undergo a slower blue staining reaction . If the fruit bodies are not uprooted and only the top of the cap is examined , G. cyanescens can be confused with young Russula <unk> mushrooms . 
