SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c0bbf4ad9dcdbd36d938d6a747d41685146744eb903ca6207cfd705c46f96c3' 
  AND token = 'Jw7jImRaubApxqtJYT6WsFWZf4YZfC6qfMX/O2WXvCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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