SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0734676766a5f49d1444b66b9421c30385fb6561b708cb3316fd38dda78d905c' 
  AND token = 'Lnxui/aWVQFTUWRDmOHUWDH+ypwoUnGwHr34/jqT1Go=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}