SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '27cea84d5b7c0d2d2db1227626f92b9225a24ef9d813d510c684f05c3d4d0362' 
  AND token = 'ZVGTWNDT5DiPy0VnQbx5lK4KxcvRHSnTga5EnRvZu+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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