SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4642f1333209e4cc11ee788adb86fffc76571b2e7783eb1d22d80f04d543e135' 
  AND token = '650oYvnB7iKC5Zu7YVfK/2p6tIjWkjeEd0R0/PrjhVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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