SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'aca1f81420047e24d0d541227b95244831f91ea3920bab708070ff0ee9ecfcf2' 
  AND token = 'xnveqAzRTDc3M50uK6EKcbu1ctxBrViJFHd3iRVOXDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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