Amphicteis dalmatica Hutchings & Rainier, 1979

Wang, Weina, Sui, Jixing, Li, Xinzheng, Hutchings, Pat & Nogueira, Joao Miguel de Matos, 2020, A new species of the genus Amphicteis Grube, 1850 (Annelida, Ampharetidae) from the Yellow Sea, China, together with a redescription of A. dalmatica Hutchings & Rainer, 1979, ZooKeys 988, pp. 1-15 : 1

publication ID	https://dx.doi.org/10.3897/zookeys.988.49934
publication LSID	lsid:zoobank.org:pub:EF36701A-F13A-44E6-A29C-45BE084DCA3A
persistent identifier	https://treatment.plazi.org/id/EE2CA4DF-4617-52B4-BA3E-A0954A891380
treatment provided by	ZooKeys by Pensoft
scientific name	Amphicteis dalmatica Hutchings & Rainier, 1979
status

Treatment

Amphicteis dalmatica Hutchings & Rainier, 1979 Figs 5 View Figure 5 , 6 View Figure 6 , 7 View Figure 7

Amphicteis dalmatica Hutchings and Rainer 1979: 783-786, fig. 9 A-E.

Material examined.

Type material. Australia, New South Wales, Pittwater, found in Zostera or Posidonia beds, 1-4 m deep. Holotype: AM W.8672, incomplete, 7 mm long, 2 mm wide anteriorly. Paratypes: AM W.8230, W.8242, W.8243, W.8249, W.8251, W.8252, W.8253, W.11667, W.11668, all incomplete; complete paratypes W.8243, W.8252, W.11667; W.8230 (only specimen with upper lip and buccal tentacles exposed) mounted for SEM examination.

Redescription.

Types with dorsum of anterior segments speckled with pigmented spots, pigmentation decreasing posteriorly. Pigmentation still visible after decades of storage in alcohol, although paler than when originally described (compare our Fig. 5 View Figure 5 with fig. 9 in the original description, especially the branchial pigmentation, most of which has been lost over time). Mucous tube with embedded sand and shell particles (Fig. 5A View Figure 5 ). Prostomium well developed, with a mid-dorsal trilobed process (Figs 5B, G, H View Figure 5 , 6A-C View Figure 6 ), middle lobe as paired longitudinal glandular ridges, wider distally, T-shaped, gap between glandular ridges absent (Figs 5B, G, H View Figure 5 , 6A-C View Figure 6 ); lateral lobes each with a cluster of eyespots basally. Nuchal organs as paired nuchal ridges, touching each other basally, V-shaped, lacking median gap; buccal tentacles smooth (Figs 5B-E, G-I, K View Figure 5 , 6A-C, E, F View Figure 6 ). Segment I inconspicuous, barely visible laterally, in superior view (Fig. 6B, E View Figure 6 ); segment II developed ventrally and laterally, bearing paleae, covered by branchiae dorsally (Figs 5B-D, G-I, K View Figure 5 , 6A-C, E, F View Figure 6 ). Four pairs of long and tapering branchiae, arising free from body wall in 2 transverse rows, on segments III and IV, each with 1 long and thick filament on each side, separated in left and right groups by a mid-dorsal triangular hump (Figs 5B-K View Figure 5 , 6A-C View Figure 6 ). All branchial filaments about same size, originating from segments II-V, arising as free filaments from segments III and IV, 2 pairs on each segment, in transverse rows, as follows: on segment III, outer pair originating from segment II, inner pair originating from segment III; on segment IV, outer pair originating from segment IV, inner pair from segment V (Figs 5B-K View Figure 5 , 6A-C, F View Figure 6 ). Segment II with ~10 short stout notopodial paleae on each side, arranged in shallow arcs, paleae distally pointed, with short filiform tip, frequently broken off; paleae remarkably small, about same size as notochaetae, but stouter (Figs 5B, C, G-I, K View Figure 5 , 6B, E, F View Figure 6 , 7A, B View Figure 7 ). Notopodia with capillary chaetae starting from segment III and extending through 17 chaetigers; notopodia each with a tuberculate ventral cirrus (Figs 5L View Figure 5 , 6D, F, G View Figure 6 , 7C-E View Figure 7 ); first 3 pairs aligned laterally to following pairs and increasing progressively in size, all 3 much shorter than those from segment VI onwards (Figs 5B, C, E-G, I, J View Figure 5 , 6A-C, F View Figure 6 ). Neuropodial tori with uncini from segment VI, present in 14 thoracic uncinigers; tori as raised trapezoidal structures throughout, larger on thorax (Figs 5C, D, I, L View Figure 5 , 6B, F View Figure 6 ). Continuous ventral shields present to approximately thoracic unciniger 12 (Fig. 5C, D, I, K View Figure 5 ). Elevated or modiﬁed notopodia absent. Intermediate uncinigers absent. Fifteen abdominal uncinigers with tuberculate rudimentary notopodia (Fig. 6H, J View Figure 6 ). Pinnules with tiny tuberculate dorsal neuropodial process (Fig. 6H, I View Figure 6 ). Thoracic and abdominal uncini arranged in single vertical rows with barely conspicuous subrostral process and five or six teeth in a single row over basal rounded prow; thoracic uncini with teeth progressively increasing in size until fourth, fifth (distal) tooth shorter (Figs 6K View Figure 6 , 7F View Figure 7 ); abdominal uncini with sixth tooth, when present, much shorter than other teeth (Figs 6L View Figure 6 , 7G, H View Figure 7 ). Pygidium with one pair of long, gently tapering anal cirri.

Distribution.

New South Wales, Australia.

Remarks.

Members of A. dalmatica are clearly distinct and differ from our new species in the following features. In A. dalmatica , the paleae are poorly developed, prostomial lateral lobes each have a cluster of eyespots basally, uncini have barely conspicuous subrostral process, and a distinct spotted pigmentation pattern is present on the dorsum of thoracic segments and branchiae. Members of Amphicteis hwanghaiensis sp. nov. have well-developed paleae that are twice as long as the prostomium. Uncini of A. hwanghaiensis sp. nov. have a much larger subrostral process. Furthermore, the type locality of A. dalmatica is New South Wales, Australia, in seagrass beds.