SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7af31d03390329c421615a7699cc0cc6f73f697016ead2402ac6af7422ba842d' 
  AND token = 'mBylemFjoyUp5gnHoHe6bPMhO47C1nA5rdYBFXPDyqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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