SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1d69780091add6b184bf24eddc0656c3d9340f0019317354e707a6abdb6062c' 
  AND token = 'sOTTIzJv5PExy76hKNdXIK6f2XBFCXIJRlXahSTFuj4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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