SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c19e0fb5733a90b661f78bf01484c99c251708966b8dfded84d62dbdc890953f' 
  AND token = 'Lzm3mZrtxWO7B8eUYRE/aIkBGZ6H1YJ4A/ZtjcxpRo0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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