It's very interesting-looking. But I thought junipers were scale-foliage conifers. Maybe it's showing juvenile-foliage?

I thought so too, but Japanese sources list it as a conifer in the Cupressaceae (cypress) family, under the genus Juniperus.

Tosho is not a registered cultivar but merely a common or group name for any Juniperus rigida or needle juniper. They all have short, sharp, twisted needles and with training and wiring, can be maneuvered into a weeping form. And depending on species or cultivar, junipers can present with a range of foliage textures, not necessarily just juvenile versus adult.

I did some digging, and this is what I found "google translated" : In bonsai, this tree is familiar with the name of "tousho (mushi)", but it is commonly referred to as "mouse." Coniferous trees of the family of Cypress family are native to hills and granites south of Tohoku in Japan. Slow growth and poor environment are prone to stake. This is a weeping variety where the leaves are curled and the branches become a cloudy dragon. The leaves are shorter than pine, but they are thinner and sharper to stir rats, but they are also very easy to wither and take a lot of effort to pick up sprouts so they are a favorite tree for a professional.
Scientific name: Juniperus rigida