From Fabulae Syrae (LLPSI series), Ch. XXVIII

[Imber Ranae]

Yes, exactly; I couldn't see anything explicitly linking ipsa or extendens to captam (as agents) so the whole thing felt awkward and strange to me. I'd have been far happier if the participle had been in the ablative (e.g. manibus extensis.)

Even if it's not as explicit a marker as you might have liked, the word order is nevertheless very suggestive of it.