Papua New Guinea and Solomon Islands morph

Figs 2 (as PNG and Sol), 4H–L

Material examined

Sequenced material

16 sequenced specimens (Table 1).

Not sequenced material

SOLOMON SEA • 1 lv; SE Engeneer group Island; 10°45′ S, 151°06′ E; 470–526 m deep; MADEEP; stn DW4300; MNHN IM-2013-45679 • 1 lv; SE of d’Entrecasteaux Islands; 9°48′ S, 151°33′ E; 278– 420 m deep; MADEEP; stn DW4314; MNHN IM-2013-45800 .

PAPUA NEW GUINEA • 1 lv; N Cape King William; 6°3′ S, 147°36′ E; 450–480 m deep; PAPUA NIUGINI; stn DW3992; MNHN IM-2013-19808 • 1 lv; 6°00′ S, 147°38′ E; 785 m deep; PAPUA NIUGINI; stn DW3992; MNHN IM-2013-19856 .

Remarks

The population from the Solomon Islands and Papua New Guinea is molecularly heterogeneous; although most of them forming a highly supported clade (Fig. 2), some specimens are scattered along the tree. One specimen (MNHN IM-2009-23330, Fig. 4L) groups with the morph from south of New Caledonia; while another (MNHN IM-2009-22244, Fig. 4K) groups with the specimens from north of New Caledonia sharing the same haplotype (Fig. 3). In total, seven haplotypes were identified (two from the Solomon Islands and five from Papua New Guinea).

Shell large (SL up to 81.2 mm (MNHN IM-2013-45800), although most specimens are below 55 mm), resembling the population from north of New Caledonia, although generally of darker orange-brown colour and lacking the purplish colouration of the callus that is often present in the northern New Caledonia morph. Upper teleoconch whorls sometimes with obtuse calloused carina. Upper anterior band either evenly strongly convex or with poorly defined submedian carina, lower anterior band always yellow-brown, although sometimes very light. Columellar ridges differently pronounced, 3–7 in number.

This form was described as Amalda vernedei herlaari van Pel, 1989 (Arafura Sea, no exact locality), and later considered a subspecies of A. hilgendorfi (Cossignani 2015) . The shell can attain 98 mm (holotype of Amalda vernedei herlaari). Depth range 335– 785 m.