SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62655b75e8a33bc4f8c3724cd86c39991900f30fdc1b04da8ba3221fce9962c3' 
  AND token = '2JBeq0CwErfCCOq6/E7KP7TuypB00S/WtLBAguEfNMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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