SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6499704bfb58c5ce73a0eb83787cfe58d5bfc1dd5eef18a377e470821742a30' 
  AND token = 'vakSL7Cz2lA30IJApQbjZrQ9t4dFn3JyAUUBzNtwWCI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}