Diagnosis– (Emended after Tavernier et al. , 1992, p. 305.) Shallow, subdichotomous or laterally branched and/or anastomosing tubular borings sporadically radiating from a central point of entry to form a complex network. Where radial branches do not occur the tunnels may be prostrate. Secondary branching may or may not occur. Slight swelling may develop at branching nodes.

Description– Crudely palmate boring consisting of tubular tunnels, parallel to the substrate surface, each varying in diameter and length. Maximum length attained by these tubes is 2·5 mm with the diameter averaging 190 μm. Swellings are sporadically distributed along each tube and at branching nodes. Second order branching is also evident. Tubules are not prominent along the tubes, but three subvertical tubules arise proximally from the main system.

Emended diagnosis. Tunnels branch sub-dichotomously or laterally, occasionally widened at branch points, circular or ellipsoidal in cross-section, with the longer axis oriented perpendicular to the substrate surface, sending out finer tubular connections at intervals to the substrate surface. A mature boring system is organised in three concentric zones, a peripheral zone of lateral spreading with straight, shallow tunnels, a second zone behind with tunnels interconnecting to form a prostrate reticulum and branches more commonly forming deeper arches of a three-dimensional reticulum in the central zone.