SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '052c9d014f83c42918774a4fe3f2228a33bd6697954734d1b1ddfe8ab4fa2dea' 
  AND token = 'QU5FJjxM5MCS0VDNqG+wK1VIXNPinBJS1GGiOo1dC+c=' 
  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"
    }
  }
}