Australian-born Anna Butterss is a working LA bassist, who’s added low end to artists such as Jason Isbell, Phoebe Bridgers and Jenny Lewis (opening for Harry Styles, no less). They are really an upright and electric jazz player, collaborating with searching artists such as guitarist Jeff Parker (Tortoise, Isotope 217°) and drummer Makaya McCraven; they compose, too. Following on from Butterss’s appearance on LA quintet SML’s LP earlier this year, Mighty Vertebrate is their second solo outing overall – a sparkling, shape-shifting record, created as a series of playful compositional challenges, that defies categorisation. Not tied to the bass, Butterss also ranges across flute, synths and drum machine.

Parker’s presence at the heart of this niche LA jazz scene brings with it the signature cerebral groove of post-rock. Parker himself guests on Dance Steve, a beguiling, body-moving track. Lubbock, meanwhile, takes its cues wholesale from Tortoise, adding Josh Johnson’s stately sax in conversation with a mantric electric guitar motif. The slow, tender Ella is different again, recalling Angelo Badalamenti; Breadrich has hip-hop adjacent drums and Spanish-language samples. Throughout, Butterss’s bass is a discreet presence, opening the record with a funky phrase, or anchoring the sonorous, percussive Seeing You. But their hand guides Mighty Vertebrate from end to end.