*Images in development
Rock and wood borers
Shell with accessory dorsal plates, ligament supported by an internal apophysis
Shell lacking accessory dorsal plates, if apophysis present then animals worm-like
Anterior of valves entire, radially ribbed, wide pedal gape lacking, [in soft rocks]
Barnea candida
Anterior of valves with a wide pedal gape, may be closed by a smooth callum in adults
Without a siphonoplax, mesoplax large, subcircular [in wood]
Sculptural change between radial on an anterior and commarginal on posterior abrupt, divided by a radial groove
Sculptural change gradual, no radial groove present
Mesoplax large, subcircular [in wood] = Martesia juveniles
Mesoplax small, triangular in 2 pieces
Umbonal reflection septate, protoplax, mesoplax and metaplax present
Pholas dactylus
Umbonal reflection not septate, only protoplax present
Barnea parva
Shell gaping anteriorly or ventrally
Shell gaping anteriorly, lacking cardinal teeth (in wood)
Shell without apophysis, small accessory plates present
Shell with apophysis, lacking accessory plates, animal worm-like with terminal pallets
Anterior area with up to 40 oblique serrated ridges, mesoplax sharply triangular in outline
Xylophaga praestans
Anterior area with up to 50 oblique serrated ridges, mesoplax quadrant in outline
Xylophaga dorsalis
Dorsal margin of posterior area raised acute, mesoplax not calcified
Xylophaga anselli
Dorsal margin of posterior area broadly rounded, mesoplax of 2 elongate triangular plates
Xylophaga gagei
Pallets segmented and on long stalk - Bankia
Pallets not segmented, stalk short
Segments cone-shaped, cones broadly triangular with smooth margins
Bankia gouldi
Segments cone-shaped, cones tapering with serrated margins and laterally extended into long awns
Pallet may appear segmented as it has a ribbed appearance
Pallet not segmented and not ribbed
Pallet 2-3 times long as wide, outline asymmetric, papilose calcareous encrustation
Nausitora fusticulus
Pallet broad, 1.5 times long as wide
Blade broadly oval, papilose encrustation distally, brown periostracum around base
Spathoteredo spatha
Blade paddle-shaped, almost entirely calcareous, thumbnail shaped depression
Blade without thumbnail shaped depression and is either broadly oval or elongated and capped
Thumbnail shaped depression is about a quarter of the blade deep
Thumbnail shaped depression is over three quarters of the blade deep. Depression is transversely striated.
Teredora malleolus
Calacareous part single piece, cap straight sided, not divided
