Pectinaria dodeka 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 : 50-54

Pectinaria dodeka Hutchings & Peart, 2002

Figs 26–27 , Table 3

Pectinaria dodeka Hutchings & Peart, 2002: 99 – 127 , figs 11 – 12 & 14 – 15.

Material examined. Australia: Queensland: AM W.25615 (Holotype) Dunwich, Moreton Bay , 27°30’S 153°24’E, coll. F.C. Vohra, 27 Mar 1962 ; AM W.19076 (Paratype), 1 spec., Dunwich, Moreton Bay , Queensland, 27°30’S 153°24’E, coll. F.C. Vohra, 27 Mar 1962 .

Additional material examined. Australia: Queensland: AM W.30912, 1 spec., Cairns, Careening area , 16°52’S 145°49’E, 10 m, coll. CRC Reef Research Centre Ltd, 17 Nov 2001 ; AM W.199312, 3 specs, Calliope River, Gladstone , 23°51’S 151°10’E, coll. P. Saenger, 1974 ; AM W.19104, 2, specs, mouth of Brisbane River , 27°22’S 153°09’E, 2 m, coll. T. Hailstone, 1963 . New South Wales: AM W.17847, 2 specs, Lake Macquarie , 33°03’S 151°38’E, Zostera beds, coll. K. Robinson, Jul 1977 ; AM W.7724, 1 spec., Lake Macquarie, Black Neds Bay , 33°05’44”S 151°38’48”E, coll. L. Collett, Sep 1972 ; AM W.33195, 1 spec. (mounted for SEM), Cottage Point , near the shop, 33°37’S 151°12’E, 0 m, coll. P.A. Hutchings, 10 Feb 2002 ; AM W.35293, 1 spec., Cowan Creek , 33°37’S 151°12’30”E, 0 m, sand mud, coll. P.A. Hutchings, 03 Nov 1996 ; AM W.35831, 2 specs, Cowan Creek , 33°37’S 151°12’30”E, 0 m, coll. P.A. Hutchings, 03 Nov 1996 ; AM W.37739, 2 specs, Cowan Creek, Cottage Point , 33°37’08”S 151°12’21”E, 0 m, coll. P.A. Hutchings & J.Z. Silva, 15 Apr 2011 ; AM W.24053, 2 specs, Cowan Creek, Cottage Point , 33°39’S 151°10’E, coll. P.A. Hutchings, Aug 1997 .

Description. Based on all specimens examined. Preserved specimen pale or reddish in colour, conical in shape ( Fig. 26A – B ). Body length 8.1 – 22.2 mm (holotype 18.5 mm) including paleae and scaphe, width 2.0 – 4.5 mm (holotype 3.2 mm) at cephalic regions.

Cephalic veil oval, free from operculum, with 14 – 21 (holotype 16) smooth cirri on anterior margin and about 1/2 of lateral margins ( Figs 26A, G ; 27A ). Pair of ear-shaped lobes adjacent to both sides of dorsal base of cephalic veil. Buccal tentacles with longitudinal grooves, arising posterior to cephalic veil ( Figs 26A – B, F – G ; 27A – B ).

Operculum semicircular; dorsal and lateral margin well developed, smooth; ventral margin (opercular ridge) with 9 – 14 (holotype 12) pairs of golden paleae, curved dorsally, acute with extended tips ( Figs 26A – B, F – G ; 27A – B ).

First pair of tentacular cirri extending beyond tips of paleae, with annuli, arising from connection of opercular margin and paleal ridge ( Figs 26F – G ; 27A – B ). Pair of small ventral lappets present behind tentacular cirri near cephalic veil on segment 1 ( Figs 26F – G ; 27A – B ). Ventral region of segment 1 covered by buccal tentacles and ventral lobes of segment 2 ( Figs 26G ; 27A ).

Second pair of tentacular cirri extending beyond opercular margin, with annuli, on latero-median connecting ridge on segment 2, inserted more dorsally than 1 st pair of tentacular cirri ( Figs 26B, F ; 27B ). Segment 2 with smooth ventral lobes as pair of narrow ventro-lateral lobes separated by grooves from base of 2 nd pair of tentacular cirri, and pair of broad mid-ventral lobes about 4x as wide as ventro-lateral lobes ( Figs 26F – G ; 27A – B ). Segment 2 without dorsal lobe ( Figs 26G ; 27B ).

Comb-like branchiae on segments 3 – 4, consisting of series of dense, flat lamellae ( Figs 26B, F ; 27A – B ). Branchiae on segment 3 larger and inserted more ventrally than those on segment 4. Pair of small dorso-lateral glandular pads present adjacent to branchiae on segments 3 and 4 ( Figs 26B, F ; 27B ).

Distinct ventral glandular lobes present on segments 3 – 6, becoming progressively more lateral and broader on segments 3 – 5 ( Figs 26G ; 27A – B ). Hump present near branchiae on segment 4. Segment 3 with broad ventral lobe, higher at mid-line. Segment 4 with pair of broad ventro-lateral lobes and mid-ventral lobe about 1/2 width of ventro-lateral lobes, separated from those by shallow grooves. Segment 5 with pair of ventro-lateral lobes and midventral lobe about 1/3 width of ventro-lateral lobes, separated from those by shallow grooves. Segment 6 with pair of broad ventral lobes with continuous papillae, separated from each other by deep notch ( Figs 26A, G ; 27A – B ).

Notopodia other than those of segment 1 which bear paleae, on segments 5 – 21 (17 pairs), each bearing two kinds of notochaetae; one short and winged from anterior row, bordered with serrations along distal portion, covered progressively with more spines from about middle to front of wing, on anterior surface; other long, stout and straight from posterior row, tapering to an acute tip, covered progressively with more spines from mid-anterior portion to end, on anterior surface ( Figs 26A – B ; 27C ). Neuropodia, 13 pairs on segments 8 – 20, each with slightly raised torus with transverse row of uncini; each uncinus with a U-shaped anterior peg embedded into torus, several rows of minor teeth, and 2 – 3 longitudinal rows of major teeth, each with 7 – 8 teeth ( Figs 26A – B ; 27D – E ). Segment 21 with pair of ventro-lateral lobes near notopodia.

Scaphe ovoidal, flattened dorsally, divided into four anterior narrow lobes and two posterior rounded lobes on each lateral margin ( Figs 26D – E ; 27E ). Anal flap triangular tongue with extended fine tip, smooth margin, with short anal cirrus ( Fig. 26D – E ). Scaphal hooks 3 – 6 (holotype 4) pairs, amber, distinctly bent towards pointed tips ( Figs 26D ; 27F ).

Tube with wide opening, slightly curved, fragile wall made of yellow proteinaceous glue and large sand grains ( Fig. 26C ).

Methyl Green stained body distinctly green on cirri of cephalic veil, ventral lobes of segments 2–6, base of 2 nd pair of tentacular cirri, dorso-lateral pads of segments 3–4, regions adjacent to neuropodia on segments 20–21, margins of scaphe, ventro-lateral regions on posterior end of scaphe, and dorsum of anal flap except for anal cirri and margin ( Fig. 26E, F ).

Distribution. SE Queensland and New South Wales ( Fig. 1 ).

Habitat. Found in mud or mud sand from intertidal to shallow waters and in estuarine conditions.

Remarks. We have expanded the original description of Pectinaria dodeka Hutchings & Peart, 2002 , and provided additional images of the holotype and some morphological which were not included in the original descripton; 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 and 2 – 3 longitudinal rows of major teeth on uncini, and an expanded description of the scaphal lateral lobes. Pectinaria dodeka has more scaphal hooks in larger individuals; the number of cirri of cephalic veil and paleae does not significantly increase with body size ( Fig. 28 ). Pectinaria dodeka can be distinguished from other Australian Pectinaria species by the following characters: paleae with extended pointed tips, 3 – 6 pairs of scaphal hooks with distinctly curved end, 2 – 3 longitudinal rows of major teeth on uncini, ventral lobes with continuous papillae on segment 6 and the dorso-lateral lobes absent on segment 2 ( Table 3 ). Pectinaria dodeka is very similar to P. kanabinos and P. antipoda for they all have continuous papillae on the ventral lobes of segment 6. But Pectinaria dodeka may be distinguished from P. kanabinos which has cirri on lateral and posterior margins of the anal flap and 3 – 4 longitudinal rows of major teeth on uncini, whereas P. dodeka has smooth lateral and posterior margin of the anal flap and 2 – 3 longitudinal rows of major teeth on uncini. Pectinaria dodeka differs from P. antipoda which has blunt paleae, dorso-lateral lobes on segment 2, relatively more (usually 6 – 8 pairs) scaphal hooks, and two longitudinal rows of major uncinial teeth.

Figures

FIGURE 1. Distribution of the species of Amphictene, Lagis and Pectinaria in Australia.

FIGURE 26. Pectinaria dodeka Hutchings & Peart, 2002 Methyl Green stained body of Holotype (AM W.25615): A. Ventral view of entire body; B. Lateral view of entire body; D. Dorsal view of posterior end; E. Dorso-lateral view of posterior end; F. Lateral view of anterior end; G. Ventral view of anterior end. AM W.35831;: C. Tube. Abbreviations: ac, anal cirrus; af, anal flap; br, branchiae; bt, buccal tentacles; cv, cephalic veil; dlp, dorso-lateral pads; op, operculum; or, opercular rim; p, paleae; s, segment; sc, scaphe; sh, scaphal hooks; tc, tentacular cirri; vl, ventral lappet.

FIGURE 27. Pectinaria dodeka Hutchings & Peart, 2002 SEM (AM W.33195): A. Laterior-ventral view of anterior end; B. Lateral view of anterior end; C. Notochaetae, segment 9; D. Uncini, segment 9; E. Lateral view of posterior end; F. Scaphal hooks. Abbreviations: af, anal flap; br, branchiae; bt, buccal tentacles; cv, cephalic veil; dlp, dorso-lateral pads; nec, neurochaetae; noc, notochaetae; op, operculum; or, opercular rim; p, paleae; s, segment; sc, scaphe; sh, scaphal hooks; tc, tentacular cirri.

FIGURE 28. Relationship between body width and body length, number of cirri on cephalic veil, number of paleae, number of scaphal hooks for Pectinaria dodeka Hutchings & Peart, 2002.