Amphictene favona Hutchings & Peart, 2002

Zhang, Jinghuai & Hutchings, Pat, 2019, A revision of Australian Pectinariidae (Polychaeta), with new species and new records, Zootaxa 4611 (1), pp. 1-70: 7-14

publication ID

https://doi.org/10.11646/zootaxa.4611.1.1

publication LSID

lsid:zoobank.org:pub:178FED38-5FEA-417F-B5DC-807D943B641C

persistent identifier

http://treatment.plazi.org/id/586F0669-FF8F-FF81-FF7B-FCE6BFF62809

treatment provided by

Plazi

scientific name

Amphictene favona Hutchings & Peart, 2002
status

 

Amphictene favona Hutchings & Peart, 2002 

Figs 4–5View FIGURE 4View FIGURE 5, Table 1

Amphictene favona Hutchings & Peart, 2002: 99 – 127  , figs 2 – 5.

Material examined. Australia, Western Australia: AM W.25611 (Holotype), Houtman Abrolhos, Wallabi Group, 28°32’35”S 113°46’32”E, 45 m, white bleached coral algal nodules (rhodoliths), coll. P.A. Hutchings, 28 May 1994GoogleMaps  ; AM W.25403 (Paratypes), 11 specs, Wallabi Group, Houtman Abrolhos, 28°36’31”S 113°44’56”E, 46 m, bleached rubble and sponges, coll. P.A. Hutchings, 28 May 1994GoogleMaps  .

Additional material examined. Australia, Western Australia: AM W.2842, 1 spec., between Broome & Wallal, 18°58’S 121°14’E, 13 m, coll. R. Bourne, Sep 1931GoogleMaps  ; AM W.5493, 1 spec., Point Samson , 20°38’S 117°12’E, low tide, sandy mud, coll. N. Coleman, 26 Sep 1972GoogleMaps  . Queensland: AM W.2317, 2 specs, Michaelmas Cay, off Cairns , 16°30’S 146°02’E, coll. T. Iredale & F.A. McNeill, Jun 1926GoogleMaps  ; AM W.25404, 1 spec., Michaelmas Reef, No. 2 Sandbank , near Cairns , 16°35’S 146°02’E, coll. I. Loch, 07 Aug 1971GoogleMaps  ; AM W.3150, 1 spec., Hayman Island , 20°03’S 148°53’EGoogleMaps  ; AM W.5611, 1 spec., Brampton Island , 20°49’S 149°17’E, 1949GoogleMaps  ; AM W.25405, 1 spec., Capricorn Group, One Tree Island, First lagoon, 23°30’S 152°05’E, 1 m, near piecrust, coll. F. Talbot & Party, 04 Oct 1967GoogleMaps  .

Description. Based on all specimens examined. Preserved specimens pale reddish in colour, conical in shape ( Fig. 4B, CView FIGURE 4). Body length 37.6 – 97.0 mm (holotype 52.0 mm) including paleae and scaphe, width 9.0 – 23.0 mm (holotype 15.0 mm) at cephalic regions.

Cephalic veil oval, free from operculum, with 21 – 33 (holotype 23) smooth cirri on anterior margin and present on about 2/3 of lateral margins ( Fig. 4CView FIGURE 4). Pair of ear-shaped lobes adjacent to both sides of dorsal base of cephalic veil. Buccal tentacles with deep median longitudinal grooves, arising posterior to cephalic veil ( Fig. 4CView FIGURE 4).

Operculum semicircular; dorsal and lateral margin well developed, with 44 – 63 (holotype 62) triangular lappets; ventral margin (opercular ridge) with 10 – 16 (holotype 12) pairs of stout, short and golden paleae, weakly curved dorsally, blunt end without extended tips ( Fig. 4B – DView FIGURE 4).

First pair of tentacular cirri short not extending beyond tips of paleae, with annuli, arising from connection of opercular margin and paleal ridge ( Fig. 4B – CView FIGURE 4). Pair of small ventral lappets present behind tentacular cirri, near cephalic veil, on segment 1. Ventral region of segment 1 covered by buccal tentacles and ventral lobes of segment 2 ( Fig. 4CView FIGURE 4).

Second pair of tentacular cirri extending to opercular margin, with annuli, on latero-median connecting ridge on segment 2, inserted more dorsally than 1 st pair of tentacular cirri ( Fig. 4B – CView FIGURE 4). Segment 2 with ventral lobes as pair of narrow ventro-lateral lobes separated by shallow grooves from base of 2 nd pair of tentacular cirri, and pair of broad mid-ventral lobes about twice as wide as ventro-lateral lobes ( Fig. 4CView FIGURE 4). A dorsal lobe with slightly crenulate margin present on segment 2, separated by grooves from base of 2 nd pair of tentacular cirri ( Fig. 4B, DView FIGURE 4).

Comb-like branchiae on segments 3 – 4, consisting of series of dense, flat lamellae ( Fig. 4B – CView FIGURE 4). Branchiae on segment 3 larger and inserted more ventrally than those of segment 4. Pair of small dorso-lateral glandular pads present adjacent to branchiae on segments 3 and 4 ( Fig. 4B, DView FIGURE 4).

Distinct ventral glandular lobes present on segments 3 – 6, becoming progressively more lateral and broader on segments 3 – 5 ( Fig. 4CView FIGURE 4). Hump present near branchiae on segment 4. Segment 3 only with broad ventral lobe ( Fig. 4CView FIGURE 4). Segment 4 with pair of broad ventro-lateral lobes near branchiae and narrow mid-ventral lobe about 2/3 width of ventro-lateral lobes, separated from those by shallow grooves. Segment 5 with pair of broad ventro-lateral lobes and narrow mid-ventral lobe about 1/3 width of ventro-lateral lobes, separated from those by shallow grooves, usually covered by ventral lobes of segment 6 ( Fig. 4CView FIGURE 4). Segment 6 with pair of ventral lobes with contiguous rounded papillae, separated from each other by broad and deep medial groove ( Fig. 4CView FIGURE 4).

Notopodia other than those of segment 1 which bear paleae, on segments 5 – 21 (17 pairs), each bearing two kinds of chaetae; one winged, bordered with serrations along distal portion, covered progressively with more spines from about middle to front of wing, on anterior surface; other stout and straight, tapering to an acute tip, covered progressively with more spines from mid-anterior portion to tip, on anterior surface ( Figs 4B – CView FIGURE 4; 5A – CView FIGURE 5). Neuropodia, 13 pairs on segments 8 – 20, each with a slightly raised torus with transverse row of uncini; each uncinus with U-shaped anterior peg embedded into torus, several rows of minor teeth, and two longitudinal rows of major teeth, each with about eight teeth ( Figs 4B – CView FIGURE 4; 5D – EView FIGURE 5). Segment 21 with pair of ventro-lateral lobes near notopodia ( Fig. 4B – CView FIGURE 4).

Scaphe wide ovoidal, flattened dorsally, divided anteriorly into four narrow lobes and posteriorly with two rounded lobes on each lateral margin ( Fig. 4B – CView FIGURE 4). Anal flap wide, fused forming tongue-like structure with short anal cirrus, distal margin with contiguous rounded lappets ( Fig. 4FView FIGURE 4). Scaphal hooks 11 – 20 (holotype 11) pairs, amber, with blunt end, straight and slightly bent towards tip ( Fig. 4EView FIGURE 4).

Tube with wide opening, slightly curved, solid wall made of large coral sand grains ( Fig. 4AView FIGURE 4).

Methyl Green stained body distinctly green on cirri on cephalic veil, ventral lobes of segments 2–6, dorsal lobe of segment 2, dorso-lateral pads of segments 3–4, neuropodia, ventro-lateral regions adjacent to neuropodia, dorsolateral and ventro-lateral regions of segment 21, margins of scaphe, and dorsum of anal flap except for anal cirri and margin ( Fig. 4View FIGURE 4 B–C). Additionally, ventro-lateral regions with continuous transverse green dots on segments 20–21 ( Fig. 4BView FIGURE 4).

Distribution. NW Western Australia, Queensland ( Fig. 1View FIGURE 1).

Habitat. Found amongst rhodoliths, sandy mud or rubble from low tide to 46 m depth.

Remarks. We have expanded the original description of Amphictene favona Hutchings & Peart, 2002  , and provided additional images of the holotype and details on some morphological characters which were not included in the original description. These include a pair of lateral ear-shaped lobes adjacent to both sides of dorsal base of cephalic veil, pair of small ventral lappets on segment 1, pair of small dorso-lateral glandular pads on segments 3 and 4, ventral lobes on segments 3–6, U-shaped anterior peg on uncini and a more complete description of the scaphal lateral lobes. The number of paleae significantly increase with increasing body size, but the number of cirri on cephalic veil and scaphal hooks does not significantly vary with body size ( Fig. 6View FIGURE 6). Amphictene favona  can be easily distinguished from all other Australian Amphictene  species by having blunt paleae, a dorsal lobe on segment 2, segment 6 with ventral lobes having contiguous rounded papillae, uncini with two longitudinal rows of teeth and 11 – 20 pairs of blunt straight scaphal hooks (Table 1). The tubes of A. favona  are robust, white and made up of large coral sand grains. Amphictene favona  is similar to Amphictene crassa ( Grube, 1870)  described from New Caledonia, which also has blunt paleae, a dorsal lobe on segment 2, as well as ventral lobes with contiguous rounded papillae, uncini with two longitudinal rows of major teeth and a tube made from coral sand grains, but differs in the number of pairs of scaphal hooks present, less than nine pairs in A. crassa  whereas A. favona  has 11 – 20 pairs.

AM

Australian Museum

Kingdom

Animalia

Phylum

Annelida

Class

Polychaeta

Order

Terebellida

Family

Pectinariidae

Genus

Amphictene

Loc

Amphictene favona Hutchings & Peart, 2002

Zhang, Jinghuai & Hutchings, Pat 2019

2019
Loc

Amphictene favona

Hutchings & Peart 2002: 99

2002