SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2666277b5126ff9e237690f174ef16d96a1e9264a4613b924f75f7a0a4db39b6' 
  AND token = 'Yj2WJGi+4KmPq+TUHfXLj4Bm6M3XMRZQuyy+IxI3RK8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00141

JSON explain

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