Pionosyllis, Malmgren, 1867

San Martin, G & Hutchings, PA, 2006, Eusyllinae (Polychaeta: Syllidae) from Australia with the Description of a New Genus and Fifteen New Species, Records of the Australian Museum 58, pp. 257-370 : 323-324

Key to Australian species of Pionosyllis

1 Blades of compound chaetae with tendon connecting proximal tooth with margin ( Fig. 74D). Pharyngeal tooth located near anterior rim, on middle of pharynx or posteriorly in mid line ...................................................... 2

—— Blades of compound chaetae without such tendon ....................................................................... 3

2 Pharyngeal tooth located just in front of middle of pharynx. Compound chaetae including short, strongly bidentate falcigers ( Fig. 74C,D) .............................................................................................................. P. rousei n.sp.

—— Pharyngeal tooth located close to anterior margin of pharynx. Compound chaetae all elongated, with proximal tooth distinctly larger than distal tooth ............................................................................................. Pionosyllis sp.

3 Pharyngeal tooth located far from anterior rim (Fig. 65A). Some dorsal cirri inflated ......................................................................................................................... 4

—— Pharyngeal tooth located on anterior rim or close to ( Fig. 56A) .................................................. 5

4 Body dark. Inflated dorsal cirri with distal button ( Fig. 60D). Dorsoventral gradation in length of blades of compound chaetae ................................... P. fusigera

—— Body with small red spots. Inflated dorsal cirri without distal button (Fig. 65B). Inverse dorsoventral gradation in length of blades of compound chaetae ........................................................................................................... P. kalimna

5 Ventral cirri inserted medially or distally on parapodial lobes. Dorsal cirri of 2 lengths, long and filiform and extremely short, exogonid-like dorsal cirri that alternate along body ( Fig. 59A) ............................... P. corallicola

—— Ventral cirri inserted at bases of parapodia. Dorsal cirri similar throughout or else differences between short and long cirri not so pronounced ( Fig. 78A) ................................................................................................................... 6

6 Segments posterior to proventricle fused in units of 2–3 segments. Palps completely free ........................................................................................... P. yolandae n.sp.

—— Segments not fused. Palps fused at bases ...................................................................................... 7

7 Dorsal cirri (except some anteriormost) exogonid-like, short, slightly longer than parapodial lobes ............................................................................................. 8

—— Dorsal cirri long ........................................................................................................................... 10

8 Dorsal cirri more or less truncate, with some internal glands ( Fig. 70C) .......................................................................................................................... P. mariae n.sp.

—— Dorsal cirri otherwise, without internal glands ( Fig. 56D) ........................................................... 9

9 Compound chaetae including spiniger-like, with elongated blades. Dorsal simple chaetae truncate ( Fig. 56I) ................................................................ P. ancori n.sp.

—— Compound chaetae only falcigers. Dorsal simple chaetae pointed, unidentate ( Fig. 73G) ............................................................................................ P. mayteae n.sp.

10 Distinct prechaetal lobe present. Acicula straight, extending beyond parapodial lobes ( Fig. 67L). Blades of compound chaetae without long, fine spines; without spiniger-like chaetae. Large size, (> 10 mm in length) .................................................................................................. P. kerguelensis

—— Prechaetal lobe absent. Acicula distally knobbed, with 2 unequal lobes. Blades of compound chaetae with long, fine, distally ornamented spines; sometimes with spiniger-like chaetae. 5–10 mm in length ................................................................................................................................ 11

11 Without long, spiniger-like compound chaetae ........................................................................... 12

—— With long, thin, spiniger-like compound chaetae (Fig. 63D) ...................................................... 13

12 Anteriormost parapodia distinctly enlarged, with compound chaetae provided with large, thick shafts, and short blades ( Fig. 75B) .................................................................................................................................. P. serrata

—— Parapodia and compound chaetae similar throughout ......................................... P. koolalya n.sp.

13 Anterior parapodia without elongated, spiniger like compound chaetae ........................................................................................................ P. heterochaetosa n.sp.

—— Spiniger-like chaetae from anterior chaetigers ............................................................................ 14

14 Compound chaetae of anterior segments with coarse serration and distal tooth more or less broad, rounded. Falcigers without double curvature ........................................................................................................................ P. augeneri

—— Compound chaetae similar throughout. Some falcigers provided with double curvature ( Fig. 61C) ............................................... P. hartmannschroederae n.comb.