Pectinidae, Rafinesque, 1815

Dijkstra, Henk H. & Beu, Alan G., 2018, Living Scallops of Australia and Adjacent Waters (Mollusca: Bivalvia: Pectinoidea: Propeamussiidae, Cyclochlamydidae and Pectinidae), Records of the Australian Museum (Rec. Aust. Mus.) 70 (2), pp. 113-330 : 161-165

Key to genera of Pectinidae occurring in Australia

1 Shell oblong, convex, commarginally undulated or corrugated, with radial macrosculpture, lacking antimarginal microsculpture, auricles unequal, byssal notch present, ctenolium weak or absent .................................................................................................................. Hyalopecten

—— Shell circular, commarginally smooth, antimarginal microsculpture present ........................................................................................................................ 2

2 Shell circular, convex, weakly commarginally undulated or smooth, with radial, commarginal or reticulate macrosculpture and antimarginal microsculpture, auricles unequal, byssal notch present, ctenolium strongly developed in most species .............................. Delectopecten

—— Shell of most specimens deformed, lv convex, right valve flat, with antimarginal microsculpture .............................................................................................. 3

3 Shell circular, deformed, unequally convex, macrosculpture only on anterior auricle of rv, with antimarginal microsculpture, byssal notch deep, ctenolium strongly developed .................................................... Hemipecten

—— Shell circular, up to 100 mm high, almost equally convex, exterior smooth, auricles equal, internal ribs present ................................................................ 4

4 Shell circular, disc and auricles smooth, byssal notch shallow, ctenolium lacking, 20–34 single, widely spaced internal ribs present .......................................................................................................................... Amusium

—— Shell circular, up to 140 mm high, almost equally convex, exterior smooth, auricles equal, internal ribs present ................................................................ 5

5 Shell circular, disc and auricles smooth, byssal notch shallow, ctenolium lacking, 42–54 internal ribs in vague pairs .................................................... Ylistrum

—— Shell circular, lv flat, rv convex, auricles equal, ribs solid ........................................................ 6

6 Shell circular, most species solid, lv flat or slightly concave, rv strongly convex, disc radially ribbed, with commarginal lamellae, auricles equal, byssal notch shallow, ctenolium lacking in late ontogeny ................................................................................................................ Pecten

—— Shell circular, lv concave, rv convex, auricles equal, commarginal lamellae lacking on right valve, ribs solid, byssal notch moderately deep ............................................................................................................... 7

7 Shell circular, lv concave, rv strongly convex, disc simply radially ribbed, lv with weak commarginal lamellae, lacking on rv, byssal notch moderately deep, ctenolium present .................................................. Minnivola

—— Shell circular, lv flat, rv convex, auricles subequal, ribs with hollow sections .......................................................................................................................... 8

8 Shell circular, lv flat, rv convex, auricles subequal, radial ribs solid or with hollow sections, commarginal sculpture weak or lacking ....................................................................................................................... Serratovola

—— Shell circular, both valves convex, primary and secondary radial sculpture present, commarginal lamellae delicate ..................................................................... 9

9 Shell circular, solid, both valves convex, with a few strong radial plicae, numerous secondary radial riblets, commarginal lamellae delicate, auricles subequal, byssal notch weak in adult, ctenolium lacking .................................................................................................... Mesopeplum

—— Shell circular, thin, both valves convex, macrosculpture lacking from most species, antimarginal microsculpture present, auricles unequal .................................................................................................................................... 10

10 Shell circular, thin, equally convex, macrosculpture lacking from most species, antimarginal microsculpture present, auricles unequal, byssal notch relatively deep, ctenolium welldeveloped .................................................................................................................... Palliolum

—— Shell oblong, solid, radially and commarginally sculptured, auricles small and equal, byssal notch and ctenolium lacking ................................................ 11

11 Shell oblong, solid, both valves weakly convex, with primary and secondary radial sculpture, commarginal lamellae delicate and closely set, auricles small and equal, byssal notch and ctenolium lacking .................................................................................................... Anguipecten

—— Shell circular, solid, lv slightly convex, rv more convex, simply radially sculptured, commarginal lamellae delicate, auricles subequal ................................................................................................................................... 12

12 Shell, circular, solid, lv slightly convex or flat (in a few species), rv more convex, disc with radial plicae and delicate, close-set commarginal lamellae, auricles almost equal, byssal notch shallow, ctenolium lacking ........................................................................... Annachlamys

—— Shell subcircular to oblong, solid, with prominent primary radial plicae bearing nodules in most species, secondary radial riblets present .......................................................................................................................... 13 13 Shell subcircular to oblong, solid, inequivalve, equilateral, with evenly spaced primary noduliferous radial plicae, secondary radial riblets present, commarginal lamellae delicate, auricles unequal, prominently ribbed, byssal notch relatively deep, ctenolium weak .......................................................................... Bractechlamys

—— Shell oblong, solid, both valves weakly convex, auricles subequal, simply radially sculptured, commarginal lamellae delicate .................................................................................................................................... 14

14 Shell oblong, solid, inequivalve, auricles subequal, primary radial plicae evenly spaced, commarginal lamellae closely spaced, byssal notch shallow, ctenolium weak ..................................................... Decatopecten

—— Shell circular, solid, lv almost flat, rv convex, strongly radially ribbed, with commarginal lamellae, auricles unequal to equal ............................................... 15

15 Shell circular, solid, left valve almost flat, right valve convex, strongly radially ribbed, commarginal lamellae delicate, auricles unequal to equal, byssal notch shallow, ctenolium weak or lacking .................................................................................. Excellichlamys

—— Shell circular to oblong, solid, convex, with simple to quadrepartite radial sculpture, commarginal lamellae delicate .......................................................... 16

16 Shell circular to oblong, solid, both valves convex, radial sculpture simple to quadrepartite, commarginal lamellae delicate, auricles unequal, byssal notch deep, ctenolium welldeveloped .............................................................................................................. Glorichlamys

—— Shell (sub)circular, solid, both valves convex, radial plicae with prominent commarginal lamellae, auricles unequal ................................................................ 17

17 Shell (sub)circular, solid, both valves convex, with evenly spaced simple radial plicae and prominent commarginal lamellae, most species with secondary radial riblets, auricles unequal with noduliferous macrosculpture, byssal notch deep, ctenolium well developed ........................................................................................................ Gloripallium

—— Shell (sub)circular, inflated, resilifer strongly erect on one side, ctenolium on both valves ......................................................................................................... 18

18 Shell (sub)circular, inflated, lv almost flat, rv weakly convex, weakly radially and commarginally sculptured, auricles almost equal, resilifer strongly oblong on one side, byssal notch shallow, ctenolium on both valves ......................................................................... Juxtamusium

—— Shell (sub)circular, inflated, sculptured with squamous radial costae ....................................................................................................................................... 19

19 Shell (sub)circular, flattened to inflated, rv more convex than lv, sculptured with primary and secondary squamous costae, commarginal lamellae delicate, byssal notch moderately deep, ctenolium well-developed ......................................................................................... Mirapecten

—— Shell oblong, radially sculptured, weakly convex, auricles highly unequal .................................................................................................................................... 20

20 Shell strongly oblong, weakly convex, with primary and secondary radial sculpture, auricles highly unequal, byssal notch deep, ctenolium prominent ............................................................................. Complicachlamys

—— Shell oblong, many specimens deformed, flattened, weakly convex, sculptured with numerous delicate radial riblets, auricles unequal ....................................................................................................................... 21

21 Shell oblong, many specimens oblique and deformed in adult stage, weakly convex, sculptured with numerous squamous radial riblets, commarginal lamellae present, auricles highly unequal, byssal notch deep, ctenolium well-developed ....................................... Coralichlamys

—— Shell circular, solid, valves almost equally convex, auricles almost equal, radial macrosculpture present, microsculpture shagreen ................................................................................................................................... 22

22 Shell circular, solid, valve inflation almost equal, auricles almost equal, primary and secondary radial macrosculpture present, shagreen microsculpture present throughout, internal rib carinae prominent, byssal notch shallow, ctenolium lacking in adult .................................................................................................................... Equichlamys

—— Shell oblong, weakly inflated, auricles highly unequal, with radial macrosculpture, intercalated antimarginal microsculpture .............................................. 23

23 Shell oblong, weakly inflated, inequivalve, auricles highly unequal, primary (and secondary) radial macrosculpture present, shagreen microsculpture lacking from most species, antimarginal microsculpture intercalated, byssal notch deep, ctenolium well-developed ..................................................................................... Laevichlamys

—— Shell circular, solid, flattened, valves almost equally convex, auricles unequal, radial macrosculpture and shagreen microsculpture present ...................................................................................................................... 24

24 Shell circular, solid, flattened, valve inflation almost equal, auricles unequal, primary and secondary radial macrosculpture and shagreen microsculpture present, internal rib carinae weak, byssal notch deep, ctenolium well-developed ........................................................ Notochlamys

—— Shell oblong, solid, lv flattened, rv spatulate, deformed in many specimens ................................................................................................................................. 25

25 Shell oblong, solid, lv flattened, rv convex and spatulate, radial sculpture fine, scabrous, anterior auricle curved .............................................................. Pedum

—— Shell oblong, solid, flattened, weakly convex, radial macrosculpture scabrous, with shagreen microsculpture .................................................................. 26

26 Shell oblong, solid, flattened, valve inflation almost equal, auricles highly unequal, radial macrosculpture scabrous, shagreen microsculpture present, byssal notch deep, ctenolium strongly developed ............................................................................................... Scaeochlamys

—— Shell oblong, oblique in many species, flattened, weakly convex, with radial macrosculpture and shagreen microsculpture ....................................................... 27

27 Shell oblong, oblique in many species, solid to thin, flattened, weakly convex, auricles unequal, primary and secondary radial macrosculpture and shagreen microsculpture present, byssal notch deep, ctenolium well-developed .................................................................... Semipallium

—— Shell oblong, solid to thin, weakly convex, with commarginal lamellae, squamous radial macrosculpture and antimarginal microsculpture ......................................................................................................................... 28

28 Shell oblong, solid to thin, weakly convex, auricles unequal, primary and secondary squamous radial macrosculpture present, commarginal lamellae intercalated, antimarginal microsculpture present, byssal notch deep, ctenolium well developed ................................................................................................................ Talochlamys

—— Shell oblong, oblique in many species, thin, weakly convex, with squamous radial macrosculpture and antimarginal microsculpture .................................................................................................................................. 29

29 Shell oblong, many species oblique in adult stage, thin, valves weakly convex, primary and secondary squamous radial macrosculpture and intercalated antimarginal microsculpture present, byssal notch deep, ctenolium well developed ............................ Veprichlamys

—— Shell (sub)circular, solid to thin, valves equally convex, auricles unequal, delicate radial macrosculpture and antimarginal microsculpture present ...................................................................................................................... 30 30 Shell (sub)circular, solid to thin, valve inflation almost equal, auricles unequal, primary and secondary scaly macrosculpture delicate, antimarginal microsculpture intercalated, byssal notch shallow, ctenolium weak ........................................................................................ Zygochlamys

—— Shell oblong, solid, valves equally convex, auricles unequal, radial macrosculpture and herringbone microsculpture present .............................................. 31

31 Shell oblong, solid, valve inflation almost equal in most species, auricles unequal, primary and secondary spinous radial macrosculpture and intercalated herringbone microsculpture present, byssal notch deep, ctenolium well-developed ......................................... Mimachlamys

—— Shell (sub)circular, solid to thin, strongly to weakly inflated, auricles unequal, with vesicular radial sculpture and commarginal lamellae .................................................................................................................... 32

32 Shell (sub)circular, solid to thin, strongly to weakly inflated, auricles unequal, vesicular radial sculpture and intercalated commarginal lamellae present, byssal notch moderately deep, ctenolium well developed ....................................................................................... Cryptopecten

—— Shell circular, solid, valves strongly inequally convex, auricles small and almost equal, simple radial macrosculpture present ..................................................................................................................................... 33

33 Shell circular, solid, lv flattened, rv strongly convex, auricles small and almost equal, simple radial macrosculpture and closely spaced commarginal lamellae present, byssal notch deep, ctenolium present ........................................................................................................... Haumea

—— Shell oblong to (sub)circular, solid, valves almost equally convex, auricles highly unequal, radial macrosculpture and imbricate microsculpture present ............................................................................................ 34

34 Shell oblong to (sub)circular, solid, valves almost equally convex, auricles unequal, simple radial macrosculpture and commarginal lamellae present, with intercalated imbricate (early ontogeny) and radial (late ontogeny) microsculpture, byssal notch deep, ctenolium well-developed ................................................................... Volachlamys