SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2e2f539d0ddf4f29dd84798dbe27fb336bb78b50673c01fe12535276b50e3e9' 
  AND token = '9SH2F0hAFE+P6+Cr8PV+t/SuT4BUrovx5ReM3qcvtqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}