Agononida incerta

Poore, Gary C. B. & Andreakis, Nikos, 2014, More species of the Agononida incerta complex revealed by molecules and morphology (Crustacea: Decapoda: Anomura: Munididae), Zootaxa 3860 (3), pp. 201-225 : 204

Key to species of the Agononida incerta complex

This key relies mainly on two features, the shape of the anterolateral margin of the telson and the numbers of dactylar robust setae on pereopods 2–4, with colour added when known. These characters vary between individuals, on the basis of sex, size and randomly. Geography can be helpful but species do co-occur.

1. Anterolateral margin of telson of male with a solid thickened tongue-like lobe protruding posterolaterally and dorsally, ornamented with parallel ridges; of female oblique, sinuous, overlapping transverse suture as a thin short projection..................................................................................................... A. rubrizonata

– Anterolateral margin of telson never protruding in this way................................................... 2

2. Pereopod 4 merus with 1 or more facial spines beside marginal spines ( Figs 5 b, 8g; rarely on one side only or absent on both sides)............................................................................................... 3

– Pereopod 4 merus without facial spines, with marginal spines only.............................................. 6

3. Pereopods 2–4 dactyli with respectively 25–50 (median about 35), 6–31 (median about 17) and 2–19 (median about 10) robust setae along flexor margins; anterolateral margin of telson concave and smooth over anterior 70%, remainder prominent, widest well anterior to transverse suture and narrower adjacent to transverse suture ( Figs 5 a, c); transverse broad orange bands subdistally on meri of pereopods 1–4, proximally on carpi of pereopods 1–4, subdistally on carpus of pereopod 1, proximally on propodus of pereopod 1, at propodus-dactylus articulation of pereopod 1, and subdistally on propodi of pereopods 2–4................................................................................................. A. indocerta

– Pereopods 2–4 dactyli with respectively at most 28, 12, 6 robust setae along flexor margins (rarely more); anterolateral margin of telson not as above; evenly coloured or with bands distal (not subdistal) on pereopodal meri........................ 4

4. Telson anterolateral margin oblique, 3-lobed, straight over anterior 40%, convex and thickened over middle 30%, and most posterior section convex but more sharply curved anteriorly ( Fig. 8 a, 9a, e); pereopodal meri with several smaller spines between major spines along margins ( Figs 8 g, h) ( French Polynesia)............................... A. polycerta n. sp.

– Anterolateral margin of telson sinusoidal, concave and smooth over anterior 60%, remainder strongly and evenly convex, margin crenellate, rarely with obvious notch; pereopodal meri with few smaller spines between major spines along margins.... 5

5. Pereopods 2–4 meri each with 15–18 spines on extensor margin; Western Indian Ocean..................... A. africerta

– Pereopods 2–4 meri each with 10–14 spines on extensor margin; Vanuatu........................ A. vanuacerta n. sp.

6. Pereopod 2 dactylus with around 4–7 (rarely 2–11) robust setae along flexor margin............................... 7

– Pereopod 2 dactylus with at least 10 (as many as 22) robust setae along flexor margin.............................. 8

7. Telson anterolateral margin almost straight over anterior three-quarters, posterior quarter separated by shallow hiatus (Western Australia)................................................................................... A. auscerta

– Telson anterolateral margin with a strong triangular notch at 70% of length, anterior section with a thin upturned concave margin, smooth over the anterior third and denticulate of the posterior two-thirds; posterior section thickened, denticulate, oblique anteriorly and squarish posteriorly ( Figs 6 a, f) (Western Indian Ocean)......................... A. madagascerta n. sp.

8. Telson anterolateral margin sinusoidal, with small notch or step at most separating anterior concave two-thirds from more lateral third ( Figs 10 a, f, h) (central eastern Australian coast) A. tasmancerta n. sp.

– Telson anterolateral margin with deep notch or step about two-thirds along, anterior section with upturned lobe over distal half................................................................................................... 9

9. Pereopod 2 dactylus with 12 (rarely 10–18) and pereopod 3 dactylus with 1–4 robust setae along flexor margins; anterolateral margin of telson with smooth proximal concavity over anterior 70% that ends at sharp step, remainder truncate-convex, margin oblique anterior to transverse suture, with crenellate margin ( Figs 7 a, c–e; 2K, L)......................... A. norfocerta

– Pereopod 2 dactylus with 17 (rarely 4–30) and pereopod 3 dactylus with usually 6 (rarely 1–17) robust setae along flexor margins; anterolateral margin of telson with 2 notches ( Figs 4 b, c).......................................... A. incerta

Figures

FIGURE 4. Agononida auscerta. Pereopods 1, upper and lateral views: a, ovigerous female, 24 mm, NMV J 55995. Agononida incerta. Anterolateral margin of telson: b, ovigerous female, 24 mm, NMV J 5521; c, male, 28 mm, NMV J 55025.

FIGURE 5. Agononida indocerta. Male, 25 mm, PNG, MNHN IU- 2011 - 1137: a (top row, telson and detail of anterolateral margin); b, merus of pereopod 4 (showing 5 facial spines in proximal third and subdistal colour band). Ovigerous female, 24 mm, paratype, Western Australia, NMV J 57295: c, anterolateral margin of telson: d, pereopod 1, upper and lateral views.

FIGURE 6. Agononida madagascerta n. sp. Holotype, male, 20 mm, MNHN IU- 2013 - 7976: a (top row, telson and detail of anterolateral margin); b, pereopod 1, dorsal and lateral views; c – e, dactyli of pereopods 2 – 4 (with robust setae magnified). Paratype, ovigerous female, 18 mm, MNHN IU- 2010 - 1159: f, anterolateral margin of telson (line drawings to same scale).

FIGURE 8. Agononida polycerta n. sp. Holotype, supermale, 32 mm, MNHN IU- 2010 - 6095: a (top row), telson and detail of anterolateral margin; b, pereopod 1, upper and lateral views; c, abdominal somites (showing 1 ancillary spine on somite 4); d – f, dactyli of pereopods 2 – 4 (with robust setae magnified); g, merus of left pereopod 4 (showing 4 facial spines in proximal half); h, right pereopodal meri (pereopod 4 merus with 1 facial spine).

FIGURE 10. Agononida tasmancerta n. sp. Supermale, 25 mm, holotype, AM P. 90862: a (first row, telson and detail of anterolateral margin); b – d, dactyli of pereopods 2 – 4 with robust setae at greater scale; e, pereopod 1, upper and lateral view. Paratype, ovigerous female, 21 mm, AM. P. 90863: f (row), anterolateral margin of telson; g, pereopod 1, upper and lateral views. Female paratype, 28 mm, AM P. 90863: h, anterolateral margin of telson. Paratype, ovigerous female, 25 mm, AM P. 42262: i, ischium and base of merus of pereopod 4 (with 2 facial spines). Line drawings to same scales. Chelipeds to same scale.