Hamopontonia fungicola, Marin, Ivan, 2012

Marin, Ivan, 2012, The “ Hamopontonia corallicola ” Bruce, 1970 species complex (Crustacea, Decapoda, Palaemonidae): new records and new species from the Great Barrier Reef, Australia, Zootaxa 3272, pp. 35-56 : 39-45

Hamopontonia fungicola sp. nov.

( Figs. 3–7 , 14 E, F, 15F)

Material examined. Australia, GBR, Lizard Island area — Holotype, ovigerous female (pcl. 5.2 mm, tl. 19 mm) (QM W33504), allotype male (pcl. 5.2 mm, tl. 21 mm) (QM W33520) — Lagoon between Palfrey Island and south, near Channel, patch reef, LI10-051, 14°41.927’S 145°27.007’E, 8 m, on Heliofungia actiniformis , coll. I. Marin, 0 1 Sept. 2010; 1 ovigerous female, dissected (pcl. 5.8 mm), 4 males (pcl. 4.0, 4.0, 3.0, 2.7 mm) (QM W33505) — Lagoon, Channel, patch reef, LI10-039, 14°41.229’S 145°27.296’E, 10 m, on Heliofungia actiniformis , coll. I. Marin, 31 Aug. 2010; 1 ovigerous female (pcl. 6.2 mm, tl. 24mm) (QM W33503) — Mermaid Cove, North Point, back reef, LI10-047, 14°38.883’S 145°27.003’E, 6–8 meters, on Heliofungia actiniformis , coll. I. Marin, 0 1 Sept. 2010; 1 ovigerous female (pcl. 5.1 mm), 1 male (pcl. 2.5 mm) (QM W33507) — Lagoon, patch reef, LI10-059, 14°41.973’S 145°26.919’E, 6 m, on Heliofungia actiniformis , coll. I. Marin, 0 2 Sept. 2010; 1 ovigerous female (pcl. 3.5 mm), 1 male (pcl. 4.0 mm) (QM W33508) — High Rock, back reef, LI10-085, 14°49.435’S 145°33.161’E, 10–12 m, on Heliofungia actiniformis , coll. I. Marin, 0 6 Sept. 2010.

Description. Large-sized pontoniine shrimp with cylindrical slightly depressed body. Carapace swollen in central part, smooth, with large antennal tooth, without hepatic or supraorbital teeth ( Figs. 4 ). Rostrum slender, compressed, pointing distally, turned forward, reaching to distal margin of the second antennular segment; rostral formula 1–2+4–5/0 ( Fig. 4 ); dorsal rostral carina well developed reaching to distal third of carapace length, with small dorsal teeth; ventral rostral carina poorly developed, unarmed; proximal lateral rostral lamina feebly developed ( Fig. 4 b). Orbit well developed, deep, unarmed; inferior orbital angle bluntly produced distally. Pterygostomial angle produced, bluntly rounded distally.

Abdominal somites smooth; pleura of abdominal somites I–V rounded ( Fig. 1 ). Telson ( Fig. 5 d, e) relatively stout, about 2.5 times as long as proximal width, narrow medially and distally, with 3 pairs of medium submarginal dorsal spines at 0.6, 0.8 and 0.95 of telson length; distal margin of telson armed with two hook-like projections (teeth) turned downward, with distinct notch medially, notch covered with numerous simple setae ( Fig. 5 d, e).

Eyes well developed, large; eyestalk smooth, cylindrical, about 1.5 times as long as wide; cornea well developed, medium, subovate ( Fig. 4 b).

Antennula ( Fig. 5 a) well developed; basal segment stout, about 1.5 times longer than wide, with well developed slender acute stylocerite, distolateral angle with large acute triangular tooth and small rounded lobe medially ( Fig. 5 b); ventromedial tooth small; intermediate segment stout, about as long as wide; distal segment stout, as long as wide, equal to previous segment length; proximal part of upper antennular flagellum with 7 or 8 segments, shorter ramus with more than 15 segments; about 7 or 8 groups of aesthetascs present.

Antenna ( Fig. 5 c) well developed, basicerite about 1.5 times longer than wide, smooth, without distoventral tooth; scaphocerite wide, about twice longer than maximal width, reaching distal margin of antennular peduncle ( Fig. 4 b), distolateral tooth well developed, acute, small, not reaching to distal margin of blade.

Mouthparts characteristic for the genus and previously described species. Maxilliped III ( Fig. 5 f) with slender unarmed segments; ischiomeral sement about 6 times longer than wide; antepenultimate segment about 3.5 times longer than wide; penultimate segment tapering distally, about 2.5 times longer than wide.

Pereiopod I with relatively slender segments, without specific features; coxal segment as long as wide, with distoventral lobe; basis as long as wide; ischium about 3 times longer than wide; merus slender, about 3 times as long as wide; carpus about 5 times as long as wide, slightly shorter than carpus; propodus about 5 times longer than wide, about twice longer than chela, slightly flaring distally; palm cylindrical, about 2.5 times longer than wide; fingers slender, about 4 times as long as wide, with straight, smooth cutting margins and simple tips.

Pereiopods II similar in shape and size ( Figs. 3 , 6 a); with robust and smooth segments; coxal segment as long as wide, with small distoventral lobe; basis as long as wide; ischium about 3 times longer than wide; merus robust, about 3 times longer than wide, with straight lateral margins; carpus triangular, stout, flaring distally, overlapping carpo-propodal articulation, with smooth distal margin ( Fig. 6 a); palm ( Fig. 6 a) cylindrical, smooth, about 4 times as long as wide, with straight margins; fingers relatively slender, about twice shorter than palm, about 4 times as long as wide; fixed finger (pollex) compressed, about 3 times longer than wide, with two medial teeth situated on proximal third of length, with simple sharp curved tip, with small medial depression opposite to tooth on movable finger; movable finger (dactylus) slender, compressed, with large tooth situated on proximal third of the cutting margin, with simple curved tip ( Fig. 6 b).

Pereiopod III with smooth slender unarmed segments ( Fig. 6 c); coxal segment as long as wide, unarmed; basis as long as wide; ischium robust, about twice longer than wide; merus slender, about 5 times as long as wide; carpus about twice longer than wide, about third of the length of propodus and merus; propodus relatively slender, about 6.5 times as long as proximal its width, with smooth unarmed margins, without ventral or distoventral teeth; dactylus simple, with basal part about 1.5 times as long as wide, with simple slender and curved unguis ( Fig. 6 d). Pereiopods III–V similar.

Pleopods normal, without specific features. Uropods slender, slightly exceeding telson; distolateral margin of uropodal exopod rectangular with small movable distolateral spine, fixed tooth absent.

Males are morphologically similar to females, but smaller in size, with more developed equal pereiopods II ( Fig. 3 b).

Differential diagnosis. The species clearly differs from its congeners in having larger size, equal large and stout pereiopods II both in females and males, slender and large fingers of pereiopods II, different proportions of distal segments of pereiopod III. The distinctive coloration and association with different host coral also clearly separate the species from the congeners.

Coloration. Body, appendages, telson and uropods generally transparent covered with numerous tiny red dots; two irregular large uniform whitish-green patches covering dorsal and lateral surfaces of carapace and abdominal somites II–IV, respectively ( Fig. 7 A–E). Males possess smaller and less marked dorsal patches; young individuals completely transparent ( Fig. 7 F). The new species is clearly distinguished from H. corallicola by mainly transparent appendages covered with tiny red dots and the presence on only two large uniformly white or creamy white patches on carapace and abdomen. For other color differences of the species from the congeners see below.

Measurements. The largest collected ovigerous female has pcl. 6.2 mm, tl. 24 mm; the largest male — pcl. 5.2 mm, tl. 21 mm.

Host. Mature individuals (ovigerous females and large-sized males) were found exclusively in association with anemone-like fungiid coral Heliofungia actiniformis (Quoy & Gaimard, 1833) (Hexacorallia, Scleractinia , Fungiidae ) ( Fig. 15 E); numerous probably non-mature transparent individuals or, possibly young males, were usually observed on the surface of large mushroom corals like Fungia spp, Herpolitha sp. or Ctenaspis echinata (Pallas, 1766) (Fungiidae) . Other macrosymbionts found on Heliofungia at the Lizard Island are pontoniine shrimp Cuapetes kororensis ( Bruce, 1977) ( Marin & Caley 2011) and an unidentified species of the pontoniine shrimp genus Ancylomenes Okuno & Bruce, 2010 .

Etymology. The species is named after its association with mushroom corals of the family Fungiidae (Hexacorallia, Scleractinia ), mainly Heliofungia actiniformis (Quoy & Gaimard, 1833) .

Distribution. Probably widespread Indo-West Pacific species; numerous photos of the species are published on the WWW from different localities through the Indo-West Pacific region. In this paper the species reported from the Great Barrier Reef of Australia (type locality) only.

Figures

FIGURE 1. Hamopontonia corallicola Bruce, 1970, ovigerous female, pcl. 3.0 mm, QM W 33500 (a, b, e – g), ovigerous female, pcl. 3.2 mm, QM W 33502 (c), male, pcl. 2.7 mm, QM W 33501 (d): a— general view; b, c— carapace, mesial view; d— carapace and two first pairs of pereiopods; e— telson; f— major pereiopod II; g— minor pereiopod II.

FIGURE 3. Hamopontonia fungicola sp. nov., ovigerous female, pcl. 5.8 mm, QM W 33505, general lateral view (a) and male, pcl. 4.0 mm, QM W 33505, carapace and first two pairs of pereiopods (b).

FIGURE 4. Hamopontonia fungicola sp. nov., front of carapace: a, b— ovigerous female, pcl. 5.8 mm, QM W 33505; c— holotype female, pcl. 5.2 mm, QM W 33520; d— male, pcl. 4.0 mm, QM W 33505; e— male, pcl. 3.0 mm, QM W 33505.

FIGURE 5. Hamopontonia fungicola sp. nov., ovigerous female, pcl. 5.8 mm, QM W 33505: a— antennula; b— distal margin of basal antennular segment and intermediate segment of antennula; c— antenna; d— telson and uropods, dorsal view; e— proximal part of abdominal somite VI and telson, mesial view; f— maxilliped III.

FIGURE 6. Hamopontonia fungicola sp. nov., ovigerous female, pcl. 5.8 mm, QM W 33505: a— chela of pereiopod II; bsame, fingers; c— pereiopod III; d— dactylus and distal part of propodus of pereiopod III.

FIGURE 7. Coloration of Hamopontonia fungicola sp. nov.: A, B — ovigerous female, pcl. 5.8 mm, QM W 33505; C, E — ovigerous female, pcl. 6.2 mm, QM W 33503; D — holotype female, pcl. 5.2 mm, QM W 33520; F — male, pcl. 4.0 mm, QM W 33505.

FIGURE 14. Pontoniine shrimps of the genus Hamopontonia Bruce, 1970 on their hosts: A, B — Hamopontonia corallicola Bruce, 1970, ovigerous females, on Goniopora sp. (Poritidae); C, D — Hamopontonia physogyra sp. nov., ovigerous female (C) and male (D), on Physogyra lichtensteini Milne-Edwards & Haime, 1851, (Caryophyllidae); E, F — Hamopontonia fungicola sp. nov., ovigerous female (E) and male (F), on Heliofungia actiniformis (Quoy & Gaimard, 1833) (Fungiidae).

FIGURE 15. Pontoniine shrimps of the genus Hamopontonia Bruce, 1970 and their hosts. Ovigerous female of Hamopontonia corallicola Bruce, 1970 (B) and stone coral Goniopora sp. (A). Ovigerous female and male of Hamopontonia physogyra sp. nov. (D) and bubble coral Physogyra lichtensteini (C). Ovigerous female of Hamopontonia fungicola sp. nov. (F) and fungiid coral Heliofungia actiniformis (E).