SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1cef45d53bc80c2009e8f16975407a94dbc603d02f866ffaee219f0f97817f82' 
  AND token = 'ofVwyGc3gAYwHshHPNm9kxqHzIgDsmqGdDKsBKlWaow=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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