SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'aa7cd47f5b92de19a63a0cbf317246a8576df2e6ac046dd6b3e0b43a6c5b74fe' 
  AND token = 'QjCtkXuFjLkvXBz5v4oWXZhyWJy+zJUMf0q2JwR0Ijw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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