Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2a3a23ee855f8fc6854e1dbeaa21f7d19211af99b4bbb46bb065b6b21739946' 
  AND token = 'sq8vYrhaG3W521Za0GUZVj0nh0pZbS0etSVcAg5nQLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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