Pectinaria carnosus Wong & Hutchings, 2015

Zhang, Jinghuai & Hutchings, Pat, 2019, A revision of Australian Pectinariidae (Polychaeta), with new species and new records, Zootaxa 4611 (1), pp. 1-70 : 48-50

publication ID	https://doi.org/ 10.11646/zootaxa.4611.1.1
publication LSID	lsid:zoobank.org:pub:178FED38-5FEA-417F-B5DC-807D943B641C
persistent identifier	https://treatment.plazi.org/id/586F0669-FFA6-FFBD-FF7B-FE0BBC312FD3
treatment provided by	Plazi
scientific name	Pectinaria carnosus Wong & Hutchings, 2015
status

Treatment

Pectinaria carnosus Wong & Hutchings, 2015 View in CoL

Fig. 25 View FIGURE 25 , Table 3 View TABLE 3

Pectinaria carnosus Wong & Hutchings, 2015: 733 – 744 View in CoL , Figs 5 – 7 View FIGURE 5 View FIGURE 6 View FIGURE 7

Material examined. Australia: Queensland: AM W.47431 (Holotype) Lizard Island , Coconut Beach reef walk, 14°41’03”S 145°28’E, 0 m, under boulders and Halimeda , coll. P.A. Hutchings & M. Capa, 25 Aug 2010 GoogleMaps .

Additional material examined. Australia: Queensland: AM W.50700, 1 spec., Lizard Island, Watsons Bay , 14°39’31”S 145°27’11”E, 9 m, coarse sand under rubble, Coll. M. Porter, M. Bok & M. Capa, 21 Sep 2016 GoogleMaps .

Description. Based on the two specimens from Lizard Island. Preserved specimen pale cream in colour ( Fig. 25A – B View FIGURE 25 ). Body with white coral sand grains in gut, curved dorsally, wide, robust and conical in shape ( Fig. 25A – B View FIGURE 25 ); approximately 22.0 – 38.2 mm (holotype 22 mm) in length including paleae and scaphe, width 8.0 – 12.8 mm (holotype 8.0 mm) at cephalic regions.

Cephalic veil widely oval, free from operculum, with 20 – 27 (holotype 20) smooth cirri on anterior margin and 2/3 of lateral margins, six pairs of long cirri on lateral margins ( Fig. 25 View FIGURE 25 A– B). Pair of ear-shaped lobes adjacent to both sides of dorsal base of cephalic veil. Buccal tentacles with deep medial longitudinal grooves, arising posterior to cephalic veil ( Fig. 25A View FIGURE 25 ).

Operculum semicircular; dorsal and lateral margins well developed, smooth; ventral margin (opercular ridge) with 9 – 12 (holotype 9) pairs of stout and golden paleae, slightly curved dorsally, with blunt tips ( Fig. 25A – B, D View FIGURE 25 ).

First pair of tentacular cirri short with annuli, not extending beyond tips of paleae, arising from connection of opercular margin and paleal ridge ( Fig. 25B, D View FIGURE 25 ). 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. 25A View FIGURE 25 ).

Second pair of tentacular cirri short not extending beyond opercular margin, with annuli, on latero-median connecting ridge on segment 2, inserted more dorsally than 1 st pair of tentacular cirri ( Fig. 25A, D View FIGURE 25 ). Segment 2 with 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 three times as wide as ventro-lateral lobes. Segment 2 with pair of dorsolateral lobes, about 1/3 width of segment 2 dorsally, connected to base of 2 nd pair of tentacular cirri ( Fig. 25D View FIGURE 25 ).

Comb-like branchiae on segments 3 – 4, consisting of series of dense, flat lamellae ( Fig. 25A – B View FIGURE 25 ). Branchiae on segment 3 larger and inserted more ventrally than those of segment 4 ( Fig. 25A – B View FIGURE 25 ). Pair of dorso-lateral glandular pads present adjacent to branchiae on segments 3 and 4, about 1/4 dorsal width of segment 3 ( Fig. 25B, D View FIGURE 25 ).

Distinct ventral glandular lobes present on segments 3 – 6, becoming progressively more lateral and broader on segments 3 – 5 ( Fig. 25A – B View FIGURE 25 ). Hump present near branchiae on segment 4. Segment 3 with pair of broad ventral lobes separated by shallow groove. Segment 4 with pair of 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 mid-ventral lobe about 1/3 width of ventro-lateral lobes, separated from those by shallow grooves. Ventral lobes of segment 6 distinctly swollen, as pair of wide ventro-lateral lobes and pair of mid-ventral swellings, separated from each other by shallow grooves ( Fig. 25 View FIGURE 25 A–B).

Notopodia other than those of segment 1 which bear paleae, on segments 5 – 21 (17 pairs), each bearing two kinds of notochaetae, most broken ( Fig. 25A – B View FIGURE 25 ). Neuropodia, 13 pairs on segments 8 – 20, each with 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 7 – 8 teeth ( Fig. 25B, I View FIGURE 25 ). Segment 21 with ventrolateral lobes near notopodia ( Fig. 25E – F View FIGURE 25 ).

Scaphe long ovoidal, flattened dorsally, divided into four anterior narrow lobes and two posterior long and rounded lobes on each lateral margin. ( Fig. 25E – F View FIGURE 25 ). Anal flap broad tongue, with smooth margin, anal cirrus absent ( Fig. 25G View FIGURE 25 ). Scaphal hooks 6 – 9 (holotype 6) pairs, yellow or amber, with blunt tip, curved distinctly, located anterior to dorsal margin of scaphe ( Fig. 25F, H View FIGURE 25 ).

Tube with wide opening, slightly curved, solid wall made of fine sand, corallite and shells ( Fig. 25C View FIGURE 25 ).

Methyl Green stained body distinctly green on cirri of cephalic veil, ventral lobes of segments 2–6, dorsolateral pads of segments 3–4, neuropodia on segments 20–21, margins of scaphe, and ventro-lateral regions on scaphe ( Fig. 25 View FIGURE 25 ).

Distribution. Lizard Island, Queensland ( Fig. 1 View FIGURE 1 ), known only from type locality.

Habitat. Found in shallow waters in coarse sediment.

Remarks. We have expanded the original description of Pectinaria carnosus Wong & Hutchings, 2015 and the diagnostic features of this species to include having pair of ear-shaped lobes adjacent to both sides of dorsal base of cephalic veil, pair of ventral lappets on segment 1, 2 nd pair of tentacular cirri and pair of dorso-lateral lobes present on segment 2, pair of dorso-lateral pads on segment 3 and 4, uncinus with U-shaped anterior peg and two longitudinal rows of major teeth, 6 – 9 pairs of scaphal hooks, ventral lobes of segments 6 distinctly swollen ( Wong & Hutchings, 2015: figs 5 – 6). This species P. carnosus can be easily distinguished from all species of Pectinari a as it has distinctly swollen ventral lobes with smooth margins on segment 6 ( Table 3 View TABLE 3 ), and an anal cirrus absent on the anal flap. Pectinaria carnosus is similar to P. antipoda and Pectinaria sp. from Australia, as all have blunt paleae, dorso-lateral lobes and two longitudinal rows of major teeth.