A worldwide community photographing and learning about wildlife
Tibicen canicularis
In this case - 100% certain this is pruinosus.
Locality checks + body shape & pruinosity support pruinosus over related taxa (linnei or canicularis).
T. canicularis is a northern species and does not actually occur in LA (there are old reports based on erroneous id's) + linnei is not well recorded in the trans-Mississippi South.