SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bdc86d5be38b18f7541ccb732b96bd573bf2346d8b79e065028a5bf2a582f5de' 
  AND token = '3KzRosKoeYd4PVuJekgnAdeDDo3pbwiSMZdGFKcVkB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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