part of continuous with maxillary segment adult apodeme apodeme of rostrum-haustellum joint fly_anatomy.ontology maxillary apodeme Y-shaped apodeme cardio-stipital element of lacinia FBbt:00003517 Apodeme that facilitates rotation of haustellum relative to the rostrum (McKellar et al., 2020). One (ventroposterior) arm is attached to the external cuticle of the rostrum, continuous with the lacinia (Grimaldi, 1994; McKellar et al., 2020). An anterior arm is continuous with the external cuticle of the haustellum (McKellar et al., 2020). A dorsal arm is free and forms the insertion site for proboscis muscle 4 (McKellar et al., 2020). This muscle is also attached to a rigid part of the rostrum, so that it rotates the apodeme and extends that haustellum as it contracts (McKellar et al., 2020). proboscis lacinia