SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ae405ca3564e0afb116a8add7d0f2fe8d00f8b05582a2057269e5cbea5a0a6f' 
  AND token = 'WQOssDlGqsy+9aekhgBfSnLB5hcwT+4HFBpmwD/UT2E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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