SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47b96f61fd7f90d9226b535902e7f14e9ba77d67af52a3c4a015053725d7010e' 
  AND token = 'znqyQhsu21mQOHoEliHjmnpX/Qt+zTZqgyHBleudwnE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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