SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddf84a35fd3e6972904b4941a432dd89d9bbfdd3d70630ad42aa76449be1bdc9' 
  AND token = 'Q8s6KF27bWAnGqVSVR661V9X7INiKbqKanRhiobGBEQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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