SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da705105d55e28d6d75f90380dc6501d95fe242fdd5bf1b2fb644a35ce0a8419' 
  AND token = 'UlniCZwNee0+h+LMsTvVVqH7oArlUdiJ84wwSDeBf0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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