Complicachlamys wardiana Iredale, 1939

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 : 227-230

Complicachlamys wardiana Iredale, 1939

Figs 59D–E,G–H,J–K, 60, 61B–C

Pecten dringi Reeve, 1853 : sp. 152, pl. 33, fig. 152a (in part); Wagner, 1989b: 114, figs 6–7 (paralectotypes).

Complicachlamys wardiana Iredale, 1939: 362 , pl. 5, figs 25–25a; Wagner, 1989b: 114, fig. 8 [holotype]; Dijkstra, 1991: 37; Lamprell & Whitehead, 1992: [28], pl. 12, fig. 73; Slack-Smith & Bryce, 2004: 236; Taylor & Glover, 2004: 262; Raines & Poppe, 2006: 186–187, lower figs; pl. 89, figs 1–3; pl. 135, figs 1–7; pl. 190, figs 1–9; Huber, 2010: 209; Raines, 2010: 618, pl. 1000, figs 1–7; Dijkstra, 2013: 57, pl. 15, figs 3a–d, pl. 28, figs 1a–b.

Semipallium wardiana (Iredale) .–Abbott & Dance, 1982: 308, fig.; Wang, 2002: 217, pl. 3, fig. 4.

Semipallium (Semipallium) fulvicostatum (A. Adams & Reeve) .– Wang, 1985: 502, fig. 2 (misidentification).

Semipallium luculentum (Reeve) .–Springsteen & Leobrera, 1986: 328, pl. 93, fig. 15 (misidentification).

Complicachlamys dringi (Reeve) .–Lamprell & Whitehead, 1992: [28], pl. 12, fig. 72 (in part).

Semipallium fulvicosta (A. Adams & Reeve) [sic].–Xu & Zhang, 2008: 87, figs 247a–c (misidentification).

Type data. Holotype (pr) AM C.090373 (Fig. 59E, G). Type locality: QLD, Whitsunday Passage , Hayman Island.

Comments on type data. The paralectotypes of Pecten dringi Reeve, 1853 are specimens of Complicachlamys wardiana Iredale, 1939 from Bathurst Island ( Wagner, 1989b: 114).

Figure 59. A, B, Serratovola pallula Dijkstra , pair, AM C.165231, 72 nautical miles NNW of Dampier, WA, 110 m; rv exterior (A), lv exterior (B). C, F, Serratovola rubicunda (Récluz) , separate valves, AM C.151488, S of Swain Reefs, E QLD, 100 m; rv exterior (C), lv exterior (F). D, E, G, H, J, K, Complicachlamys wardiana Iredale , 3 pairs; (D, H) AM C.057307, intertidal, Entrance Point, Broome, WA; lv exterior (D), rv exterior (H); (E, G) AM C.090373, holotype of C. wardiana, Hayman Island, Whitsunday Passage, QLD; rv exterior (E), lv exterior (G); (J, K) AM C.303787, East Arm, Darwin Harbour, NT, 12°30'S; lv exerior (J), RV exterior (K). I, L, Coralichlamys madreporarum (G. B. Sowerby II) , pair, AM C.303771, Drimmie Head, Melville Bay, Gove, NT; rv exterior (I), lv exterior (L). Scale bars represent 10 mm (A, B, I–L), 20 mm (C, E–G, J, K), 30 mm (D, H).

Figure 60. Distribution of Complicachlamys wardiana Iredale.

Additional material examined. — AUSTRALIA: QUEENSLAND: Torres Strait, off Murray Island, 9°56'S 144°04'E, dead, 9–15 m (1 v,C.372282);Torres Strait, 10°0'S 143°0'E, dead (1 pr, C.047358); Torres Strait, Thursday Island, 10°35'S 142°13'E, alive (1 pr, C.097531); Cape York, Evans Bay, 10°42.4'S 142°32.7'E, alive (1 pr,C.007539);Cape York Peninsula,Albany Passage, 10°45'S 142°37'E, dead, 7–26 m (4 v, C.036130; 1 pr, C.055670); Gulf of Carpentaria, Jardine River mouth, 10°56'S 142°13'E, alive (1 pr,C.012052); N Gulf of Carpentaria, 11°30'S 140°26'E, dead, 65 m (1 v,C.369640);Gulf of Carpentaria, Mapoon, 11°58'S 141°53'E,dead (1 v,C.131553); Gulf of Carpentaria, beaches around Mapoon, 11°58'S 141°53'E, dead (3 v, C.014167); N Gulf of Carpentaria, 12°05'S 139°19.5'E, dead, 62 m (1 v, C.369642); W Gulf of Carpentaria, 14°17'S 137°51'E, dead, 59 m (1 v, C.369641); Gulf of Carpentaria, W of Mitchell River, 15°09.5'S 141°09.8'E, alive, 22 m (1 pr, C.372262); E Gulf of Carpentaria,W of Nassau River, 15°51'S 140°54.2'E,alive, 22 m (1 pr,C.369639);E Gulf of Carpentaria, W of Nassau River, 15°53.5'S 140°42' E,dead, 25.6 m (1 pr,C.369638); GBR, off Grenville, Sunday Island, 11°56' S 143°12'E, dead (1 v, C.075232); GBR, Penguin Channel, 16°15'S 145°31'E, alive, 22–25 m (1 pr,C.372300); GBR, Low Isles, 16°23'S 145°34'E, 16–22 m, dead (2 v, C.372302);Gulf of Carpentaria,Forsyth Island, 16°50' S 139°06'E,dead,beach (4 v,C.014848);Kurramine Beach,S of Innisfail, 17°47' S 146°06'E, dead (1 v, C.372299); Forrest Beach, S of Lucinda, 18°43'S 146°18'E, dead (1 v,C.133072);Magnetic Island, 19°08'S 146°50' E,dead (1 v,C.075241);Townsville, 19°16'S 146°49' E, dead (4 v, C.131554; 1 v, C.133554);off Bowen, 19°44'S 148°14'E, dead, 40 m (1 v, C.372308); GBR, E of Bowen, 19°45.7'S 148°19'E, dead, 46 m (1 v, C.372307); Port Molle, S of Shute Harbour, 20°0'S 148°50'E, alive, 18 m (2 pr, C.012053); GBR, Whitsunday Islands , off Hayman Island, 20°03'S 148°53'E, dead, 9 m (1 v, C.100370); GBR, Whitsunday Islands , Hayman Island, 20°03.6'S 148°53.5'E, alive (1 pr, C.090373; 1 v, C.100361); Bowen, Edgecumbe Bay, 20°08'S 148°23' E, dead (2 v, C.372305); Whitsunday Passage, Henning Island, 20°19'S 148°56'E, dead (1 v, C.372303); GBR, Whitsunday Passage, Lindeman Island, 20°27'S 149°02' E, dead (many v, C.058937); off Shaw Island, N of Mackay, 20°29'S 149°05'E, dead, 37 m (many v, C.372317); E of Mackay, 20°52'S 149°29'E, dead, 35 m (8 v, C.116563); GBR, E of Sarina, 21°27.5'S 150°08' E,dead, 42 m (1 v,C.372320);GBR,Swain Reefs, 3 km NE of W side of Bylund (Gillett) Cay, 21°42'S 152°26'E, alive, 64–73 m (1 pr + 23 v, C.372270); GBR, SE of Sarina, 21°47'S 150°34'E, dead, 59 m (1 v, C.372319); off Yeppoon, 22°30'S 151°26'E, dead, 55 m (1 pr, C.372329); Keppel Bay, 1.5 ml NW of South Keppel Island, 23°09' S 150°57' E, alive, 13–20 m (2 pr, C.372268); Keppel Bay, off Keppel Island, 23°09'S 150°56' E, dead (1 v, C.372328); Capricorn Channel, 4 ml E of North Reef, 23°09'S 151°58'E, dead, 64 m (1 v, C.372331); off South (Great) Keppel Island, 23°12'S 150°58'E, alive, 4 m (1 pr, C.372327);GBR, Capricorn Group, Wilson Island, E side, 23°18'S 151°57'E, alive (1 pr, C.372269); GBR, Capricorn Group, North West Island, 23°18'S 151°42'E, dead (3 v, C.372323); GBR, Capricorn Group, Heron Island, 23°26'S 151°57'E, dead (1 pr, C.372321); GBR, Bunker Group, off Lady Musgrave Island, 23°54'S 152°25'E, dead, 47 m (1 v, C.372330); Port Curtis, 23°55'S 151°23'E, dead (1 pr, C.047357); off Burnett Heads, 24°46'S 152°24'E, alive, 37 m (2 pr, C.097528); Hervey Bay, off Picnic Point, 25°06' S 152°49'E, alive, 9–12 m (1 pr, C.103802); Hervey Bay, S of Woody Island, 25°18.5'S 152°56'E, alive, 9 m (2 pr, C.097529). WESTERN AUSTRALIA: Shark Bay, 26°07' S 113°25'E, dead (3 v, C.119676); Exmouth Gulf, Bundegi Reef,S end, outer part of rich coral reef, 21°51.5'S 114°09.3' E, dead, 2–4 m (1 v, WAM494); Exmouth, Bundegi Reef, 21°51'S 114°11'E, alive, 6 m (6 pr + 1 v, C.369648); North West Cape, 21°49.05'S 114°14.56' E, dead, 23 m (1 v, C.369649); 40 ml S of Dampier, 21°0'S 116°06' E, dead (1 v, C.369565); Port Hedland, 20°18' S 118°35'E,alive(1 v,C.083717;1 pr,C.119677);0.5ml N of Port Smith, 18°30'S 121°47'E, dead (1 v, C.369647); Broome, Entrance Point, 18°01'S 122°12'E, alive (3 pr + 1 v, C.057307; 4 pr,C.121368); Broome, Roebuck Bay, 18°0'S 122°15'E, 0–13 m, alive (1 pr, C.092016; 1 pr, C.097530; 4 pr, C.131549; 1 v, C.369591; 3 pr, C.372263);Gantheaume Point, W of Broome, 17°59'S 122°11' E,alive (1 v, C.138836;1 pr,C.372248);Black Ledge,Roebuck Bay, S of Broome, 17°59'S 122°17'E,dead(many v,C.303788);Broome, 17°58' S 122°14'E, 16 m, dead (1 v, C.075237; 2 pr, C.103814;1 pr, C.131550;8 v, C.369589;1 pr,C.369646);Broome,Cable Beach, 17°56'S 122°12'E, dead (1 v, C.079279); Beagle Bay, 16°56'S 122°32'E, dead (10 v, C.119678); King Sound, 16°50'S 123°30'E, dead (3 pr, C.097534); Cape Leveque, 16°24'S 122°55'E, alive, 0–0.5 m (1 pr, C.057109; 1 pr, C.095975; 1 pr, C.097533); Lacepede Islands , Middle Island, 16°51.5'S 122°08'E, dead (1 v, C.069280); Cape Leveque, 16°24'S 122°55'E, dead (1 v, C.369598). NORTHERN TERRITORY: Timor Sea, 30 km W of Bathurst Island, 11°39'S 129°48'E, alive, 25 m (5 pr, NTM P008199); Darwin, 36 km off Point Charles, 12°10'S 130°22'E, dead, 27–37 m (2 v, C.131551); Darwin, West Point, 12°26.5'S 130°46'E, alive (2 pr, C.073086; 1 v, C.369579; 2 pr, C.372250); Port Darwin, East Point, 12°25'S 130°49'E, dead (1 v, C.068396; 1 v, C.111355); Port Darwin, Dudley Point, 12°25'S 130°49'E, lower eulittoral zone, alive (1 pr, C.073183); Darwin, Larrakeyah, 12°27.4'S 130°49'E, dead (1 pr, C.369643); Darwin, off Emery Point, 12°27' S 130°49'E, dead (3 v, C.369644); Darwin,Waigait, 11°28'S 130°50' E, on rocky sheltered reef, alive (many, C.111870; 9 pr, C.372251; 8 pr, C.372252);Darwin, Stokes Hill Powerhouse, 11°28'S 130°50'E, alive (1 pr, C.107994); Port Darwin, 12°28' S 130°50'E, dead, 0–10 m (2 v, C.013919; 1 v, C.019468; 1 pr, C.047361; 4 pr, C.073647; 1 pr, C.097423; 9 v, C.131217; 5 v, C.369624); near Darwin, 12°28'S 130°50'E, dead (1 v, C.092648); Darwin, N end of Casuarina Beach, Free Beach , adjacent to outlet of Sandy Creek, 12°21'S 130°53.3'E, dead (1 v, NTM P005102); Darwin Harbour, East Arm, 12°30' S, specimen illustrated in “Bivalves of Australia 1” (28, fig. 72) (AM C.303787); Darwin Harbour, reef to right of East Arm Boat Ramp, 12°29.5' S 130°53.8'E, close to channel, dead (3 pr + 3 v, NTM P002068); Darwin, Lee Point, 12°20'S 130°54'E, dead (2 v, C.077157); Darwin, Buffalo Creek, E of Lee Point, 12°20'S 130°55' E, dead (1 v, C.108668); Melville Island, Cape Conder, 11°44'S 131°17'E, dead (1 v, C.369627); Cobourg Peninsula, Smith Point, 11°07'S 132°08'E, dead (2 v, C.101950; 1 v, C.104021); Berkeley Bay, E side of Port Essington, 11°13'S 132°11'E, dead (1 v, C.122539); Arafura Sea, 125 km N of Goulburn Island, 10°23'S 133°36'E, dead, 62 m (1 v, C.369645); Arnhem Land, Boucaut Bay, 12°0'S 134°27'E, dead (1 pr + 1 v, C.061365); W Gulf of Carpentaria, Groote Eylandt, 14°0'S 136°25' E, dead(1 pr, C.097532;1 v, C.369634;1 v,C.369636);Wessel Islands ,Marchinbar Island, 11°15'S 136°38'E,dead (1 v,C.071439);Gove Peninsula,Melville Bay,Yirrkala,Dundas Beach, 12°15'S 136°45'E,dead (1 v,C.369630);Arnhem Land,Gove Peninsula,Yirrkala, 12°15'S 136°53' E, dead (1 v,C.060172).— CHINA: Kwangtung, alive, intertidal (1 pr, ZMA Moll.143060). — VIETNAM: Nha Trang, Hon Mieu, alive, 15 m (1 pr, ZMA Moll.146125). — PHILIPPINE ISLANDS : Coron, Palawan, alive, 30 m (9 pr, ZMA Moll.140839); Recodo, alive, 5 m (13 pr, ZMA Moll.141354); off Zamboanga, alive, 20–30 m (2 pr, ZMA Moll.140275).— THAILAND:Gulf of Siam,Samui Island,alive, 5–20 m (1 pr, ZMA Moll.145794). — MALAYSIA: Sentosa Island, near ferry wharf, 1°25'S 103°83.3'E,alive, upper littoral (1 pr,C.372264); Kelantan,alive, 34 m (5 pr, ZMA Moll.143063).— INDONESIA:off Bangka, alive, 7–10 m (1 pr, ZMA Moll.140093).

Description. Shell up to 60 mm high, most specimens to c. 40 mm; rather solid, somewhat prosocline, left valve flattened, right valve slightly more inflated, inequivalve, inequilateral, auricles highly unequal in shape and size, umbonal angle c. 80–85°; colour highly variable, white, cream, yellowish, orange, red, purple, brown or almost black; uniform, mottled or with paler zig-zag streaks.

Both valves with 7–9 (8 on most specimens) evenly spaced, low (in Queensland morph) to more angulate (in WA morph) radial plicae. Numerous closely spaced radial riblets on plicae (3–5) and in interspaces (7–10), with rather coarse lamellae on plicae in WA morph, lamellae delicate or lacking in Queensland morph. Microscopic interstitial commarginal lamellae in WA morph, more minute or lacking in Queensland morph. Anterior auricles much larger than posterior, with c. 8–10 fine radial riblets on left valve, c. 5–6 more prominent ones on right valve. Byssal notch deep, byssal fasciole rather broad. Functional ctenolium with c. 8 well-developed teeth.

Dimensions. Illustrated specimens: WA, Broome , Entrance Point ( AM C.057307): rv: 57.4, L 49.9 mm; lv: H 57.2, L 49.6 mm; D 12.9 mm; NT, Darwin Harbour, East Arm, 12°30'S, illustrated by Lamprell & Whitehead (1992: pl. 12, fig. 72) ( AM C.303787): rv: H 45.2, L 40.1 mm; lv: H 45.2, L 38.8 mm; D 11.8 mm. Iredale (1939: 363) stated the dimensions of the holotype as H 29.5, L 25 mm .

Habitat. Living in the intertidal to sublittoral zones, byssally attached to undersides of coral slabs on hard reef at extreme low tide, often in silty conditions. Some adults become detached and lie in the silt under slabs.

Distribution. Tropical Indo-West Pacific from China to the Gulf of Siam and from the Philippines to northern Australia (Raines & Poppe, 2006: 188); Vietnam to Australia, 0–180 m (Huber, 2010: 209); Philippines, 14–90 m (Dijkstra, 2013: 58); South China Sea (as “ Semipallium fulvicosta ”) (Xu & Zhang, 2008: 87); Indonesia, Sulawesi (Dijkstra, 1991: 38); Maximum depth range of live-taken specimens is from the intertidal zone to 180 m. Present specimens from Australia alive in the intertidal zone to 73 m.

Remarks. Specimens from northwestern Australia have coarser sculpture than those from Queensland, but specimens from central northern Australia intergrade slightly. Examined material from the Indo-West Pacific is indistinguishable from the type material from Queensland.