SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae79a30c364b943405d5865f10f452147bb93e98443419b1d54b72c726c0300b' 
  AND token = 'GgwXd6AHvjRitwTEbxTGwFFNmIswK8HUIJ0wgsUE6qg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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