SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fcb5193f37ea9cd4129deba0f5f85e5c7eaed9f66149688fca5452ed8886125' 
  AND token = '//qAwVKTyxJrGYbZzivQBduba6fUm0N9jgy6+JQGvGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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