SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dfc2aed76d17817a542b6239511cc7daf304c48b66f3ab54cd6ef2f6f2aa28d2' 
  AND token = '9Ooq5/hW6zK7IyVyIzQE1Y4OeZ9m4fnammjnn+BZUWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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