SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dc4787ae34950a067ef60693fa429f324ee554207fb1296615623b131e092dc' 
  AND token = 'pPIDTrfCaHnRpM7Y0f1/U3LIJYwY3bcMZkk3shgwUzI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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