SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d576b48117d2ed0a331ec48913b93497de4b87dacab125df22eef6181ab5526' 
  AND token = 'rKsoN0ZAAQK1OMzEKwKMZsu2Jwgq0uP/tUJHk1m+l9Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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