SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9c68e9610b53fe82c13d1a12e4269a1e4b88e7c480fd3178e2a7404df9241bc' 
  AND token = '5V9RLbVU0V0bMe5DJdfVIa7vt9TfUCo686vR/LXm0+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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