SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce65e67e8cbd0f9ade362211b53f9f15c26349760eb60ad2a3934ac457a8cfb0' 
  AND token = 'eg+GA/9Fuw+zH9thYtoou/v1pl6+tPnXVzM6GXzFdBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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