SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e05040eefb3b87043875584be0006cf49d3f034be510affb61d65659dd789e04' 
  AND token = 'bWmnfci6likLeyswLckl+7IEEnRgAd9Rrk9EBDmwB6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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