SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c3360afa193671be239424abb0089b61b7de0b5cf6754448e5a34027aafcfda' 
  AND token = 'iTmLN1p4jhMwTVmKzPyBqEJkae7MEzeVSSAUXMKxDTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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