Phylladiorhynchus laureae, Rodríguez-Flores & Macpherson & Machordom, 2021

Rodríguez-Flores, Paula C., Macpherson, Enrique & Machordom, Annie, 2021, Revision of the squat lobsters of the genus Phylladiorhynchus Baba, 1969 (Crustacea, Decapoda, Galatheidae) with the description of 41 new species, Zootaxa 5008 (1), pp. 1-159 : 74-77

Phylladiorhynchus laureae n. sp.

( Figs. 26 , 27 C–D , 33A )

Type material. Holotype. New Caledonia, LIFOU Stn 1457 20.7800°S, 167.0458°E, 5–10 m, 27 November 2000: ov. F 2.4 mm (MNHN-IU-2014-13739).

Paratypes. New Caledonia. Exp. Mont. Komac 12 m, 7 October 1993: 1 F 1.7 mm (IU-2019-2635).—LIFOU Stn 1435, 20.9200°S, 167.0116°E, 5–30 m, 8 November 2000: 1 ov. F 2.0 mm (MNHN-IU-2019-2608).—Stn 1430, Stn 1430, 20.7916°S, 167.1183°E, 20–25 m, 9 November 2000: 2 ov. F 2.2–2.4 mm (MNHN-IU-2019-2632).—Stn 1457, 20.7800°S, 167.0458°E, 5–10 m, 27 November 2000: 1 ov. F 2.4 mm (MNHN-IU-2014-13739).— Koumac 2.3 Stn KB 631, 20.52698°S, 164.02615°E, 3 m, 08 November 2019: 1 F parasitized 1.7 mm (MNHN-IU-2019- 2581).— Stn KL 39, 20.7511°S, 164.23276°E, 26 m, 10 November 2019: 2 F parasitized 1.8–2.0 mm (MNHN-IU- 2019-2582), 1 F 1.8 mm (MNHN-IU-2014-20123).—Stn ARMS 9C: 1 ov. F 1.1 mm (MNHN-IU-2014-20145).— Stn KB 659, 20.66049°S, 164.26852°E, 15 m, 21 November 2019: 1 M 2.3 mm (MNHN-IU-2014-20175) .

Mariana Islands. Guam Island. Stn GUA-645, 13.57847°N, 144.82831°E, 10 m, 25 March 2014: 1 ov. F 2.0 mm ( UF54543 ) .

Other material. Japan. Okinawa. Iriomote Is. Nakano Beach, 24.4323°N, 123.7916°E, 19 m, 9 July 2010: 1 M 2.0 mm ( UF26910 ) .

Papua New Guinea. KAVIENG Stn KS 33, 02.6366°S, 150.6450°E, 8–10 m, 13 June 2014: 1 ov. F 2.8 mm (MNHN-IU-2014-13559), 1 M 2.0 mm (MNHN-IU-2014-13645) .

Vanuatu. SANTO Stn DB 1, 15.5516°S, 167.2966°E, 15–25 m, 10 September 2006: 1 M 2.0 mm, 1 ov. F 1.9 mm (MNHN-IU-2019-2629).— Stn DR 21, 15.6083°S, 167.0233°E, 22–25 m, 15 September 2006: 1 F 1.3 mm (MNHN-IU-2014-13884).— Stn DB 29, 15.6483°S, 167.0850°E, 15 m, 17 September 2006: 1 M 1.5 mm (MNHN- IU-2019-2624).— Stn DS 49, 15.6450°S, 167.0866°E, 10–17 m, 21 September 2006: 1 M 2.4 mm (MNHN-IU- 2019-2631).— Stn DB 63,15.4483°S, 167.2633°E, 21 m, 25 September 2006: 2 ov. F 2.0– 2.1 mm (MNHN-IU- 2014-13872).— Stn DB 65, 15.4300°S, 167.2166°E, 13 m, 26 September 2006: 2 M 2.0– 2.2 mm, 4 ov. F 1.7–2.1 mm, 3 F 1.8–2.3 mm (MNHN-IU-2014-13870).— Stn DB 69, 15.4066°S, 167.2166°E, 38 m, 27 September 2006: 1 M 2.0 mm (MNHN-IU-2029-2625).— Stn DB 75, 15.3816°S, 167.1983°E, 20 m, 28 September 2006: 1 M 2.0 mm (MNHN-IU-2014-13885).— Stn FB 43, 15.4733°S, 167.2483°E, 19 m, 30 September 2006: 1 M 2.0 mm, 2 ov. F 1.7–1.8 mm (MNHN-IU-2019-2590).— Stn FB 64, 15.5900°S, 166.9866°E, intertidal, 10 October 2006: 1 M 3.0 mm (MNHN-IU-2014-13807).—no Stn number: 1 M 1.9 mm (MNHN-IU-2019-2623) .

Mariana Islands. Guam Island. Mid-western coast, at Orote northern tip, dead coral, 25 m, 20 June 2002: 2 M 1.1–1.7 mm, 1 ov. F 1.6 ( UF3122 ) .— Mariana Islands. Guam Island. Stn GUA-597, 13.57847°N, 144.82831°E, 11 m, 25 March 2014: 3 M 1.4–1.7 mm, 6 ov. F 1.5–2.4 mm ( UF54509 ).—Stn GUA-693, 13.57847°N, 144.82831°E, 11 m, 25 March 2014: 1 M 2.0 mm ( UF54510 ).—Stn GUA-698, 13.57847°N, 144.82831°E, 11 m, 25 March 2014: 1 ov. F 1.8 mm ( UF54511 ).—Stn GUA-880, 13.30553°N, 144.65257°E, 12 m, 27 March 2014: 1 ov. F 1.9 mm ( UF54503 ).—Stn GUA-877, 13.30553°N, 144.65257°E, 12 m, 27 March 2014: 1 M 1.4 mm ( UF54504 ).— Stn GUA-756, 13.30553°N, 144.65257°E, 12 m, 27 March 2014: 1 M 1.9 mm, 1 ov. F 2.0 mm, 1 F 2.1 mm ( UF54505 ).—Stn GUA-805, 13.30553°N, 144.65257°E, 12 m, 27 March 2014: 2 ov. F 2.0– 2.1 mm ( UF54506 ).— Stn GUA-810, 13.30553°N, 144.65257°E, 12 m, 27 March 2014: 1 F parasitized, 2.0 mm ( UF54507 ).—Stn GUA- 878, 13.30553°N, 144.65257°E, 12 m, 27 March 2014: 1 M 1.8 mm ( UF54508 ).—Stn GUA-947, 13.48871°N, 144.87796°E, 14 m, 28 March 2014: 1 M 1.8 mm ( UF54512 ).—Stn GUA-1216, 13.44878°N, 144.62596°E, 14 m, 31 March 2014: 2 M 1.6–2.0 mm, 1 ov. F 1.9 mm ( UF54513 ).—Stn GUA-1201, 13.44878°N, 144.62596°E, 14 m, 31 March 2014: 1 ov. F 1.5 mm ( UF54514 ).—Stn GUA-1204, 13.44878°N, 144.62596°E, 14 m, 31 March 2014: 1 M 2.0 mm ( UF54515 ) .

Northern Mariana Islands. Saipan Island. Stn SAI-442, 15.0978°N, 145.7434°E, 17 m, 11 April 2014: 4 M 1.2–2.0 mm, 5 ov. F 1.7–2.1 mm ( UF) .— Stn SAI-543, 15.0978°N, 145.7434°E, 17 m, 11 April 2014: 4 M 1.1–1.9 mm, 2 ov. F 1.7–1.9 mm ( UF54517 ) .— Stn SAI-544, 15.09782849°N, 145.7434357°E, 17 m, 11 April 2014: 1 M 2.0 mm, 2 ov. F 2.1–2.3 mm ( UF54518 ) .— Stn SAI-641, 15.15620°N, 145.6899°E, 11 m, 17 April 2014: 4 M 1.2–2.1 mm, 8 ov. F 1.8–2.5 mm ( UF54519 ) .— Stn SAI-586, 15.0978°N, 145.7434°E, 17 m, 11 April 2014: 2 M 2.1–2.4 mm, 3 ov. F 1.5–2.1 mm ( UF54520 ) .— Stn SAI-437, 15.0978°N, 145.7434°E, 17 m, 11 April 2014: 3 M 1.9–2.3 mm, 1 ov. F 1.8 mm ( UF54521 ) .— Stn SAI-708, 15.1562°N, 145.6899°E, 11 m, 17 April 2014: 2 M 1.8–1.9 mm, 4 ov. F 1.8–2.0 mm, 1 F 1.2 mm ( UF54522 ) .— Stn SAI-756, 15.1562°N, 145.6899°E, 11 m, 17 April 2014: 3 ov. F 1.7–2.1 mm ( UF54523 ) .— Stn SAI-789, 15.1562°N, 145.6899°E, 11 m, 17 April 2014: 3 M 1.9–2.3 mm, 4 ov. F 1.7–2.2 mm, 1 F 1.2 mm ( UF54524 ) .— Stn SAI-878, 15.27406°N, 145.79106°E, 9 m, 18 April 2014: 1 F 1.8 mm ( UF54525 ) .— Stn SAI-889, 15.27406°N, 145.79106°E, 9 m, 18 April 2014: 11 M 1.5–2.3 mm, 8 ov. F 1.4–2.0 mm ( UF54526 ) .— Stn SAI-957, 15.27406°N, 145.79106°E, 9 m, 18 April 2014: 3 M 1.5–2.0 mm, 5 ov. F 1.6–2.2 mm, 1 F 1.8 mm ( UF54527 ) .— Stn SAI-786, 15.15620°N, 145.68996°E, 10 m, 17 April 2014: 1 postlarvae ( UF54528 ) .

American Samoa. Olosega Island. Stn OLO-186, 14.18140174°S, 169.6267462°W, 14 m, 14 March 2015: 1 ov. F 2.0 mm ( UF54529 ) .— Tutuila Island . Stn TUT-117, 14.36046°S, 170.75024°W, 17 m, 26 February 2015: 1 M 1.7 mm, 1 ov. F 1.9 mm ( UF54530 ) .— Stn TUT-374, 14.36613333°S, 170.7628833°W, 12 m, 5 March 2015: 1 M 1.9 mm, 1 ov. F 2.0 mm ( UF54531 ) .— Rose Atoll. Stn ROS-689, 14.55965°S, 168.1601167°W, 14 m, 18 March 2015: 1 M 1.9 mm ( UF54532 ) .

Etymology. Named after our colleague and host Laure Corbari, curator of the Crustacean Collection of the Muséum national d’Histoire naturelle, Paris.

Description. Carapace: Slightly broader than long; transverse ridges with dense short setae and long and thick iridescent setae. Gastric region slightly convex with 4 transverse ridges: epigastric ridge distinct with 2 median spines, often with short scales laterally; anterior protogastric ridge not medially interrupted, extending laterally to carapace margin, sometimes followed by small scales on posterior protogatric ridge; anterior mesogastric ridge not medially interrupted, laterally continuing to first branchial spine, followed by some lateral scales; anterior metagastric ridge medially interrupted or not medially interrupted, followed always by one median scale and often other small scales in posterior metagastric region. Mid-transverse ridge not interrupted, medially depressed, cervical groove indistinct, followed by 2 not interrupted or minutely interrupted ridges, interspersed with 1–2 short lateral ridges and few short scales. Lateral margins slightly convex, with 6–7 distinct spines: first anterolateral spine well-developed, exceeding level of lateral orbital spine, second spine (hepatic) small, slightly dorsomesially from lateral margin, and followed by 5 branchial spines (3 anterior and 1–2 posterior). Rostrum leaf-like, horizontal, dorsally concave, [1.1]–1.4 × as long as broad, length [0.3]–0.4 and breadth 0.3 that of carapace; lateral margins serrated and strongly convex, with well-developed supraocular basal spines and strong subapical spines (tridentiform). Pterygostomian flap ending in sharp tooth, upper margin smooth, with series of elevated striae.

Thoracic sternum: As wide as long. Sternite 3 quadrangular, [1.5]1.0–1.8 × as wide as long, anterior margin serrated, with a median projection, anterolaterally rounded. Sternite 4 widely contiguous to sternite 3; anterolaterally serrated, surface depressed in midline, smooth; greatest width 2.6–[3.0] × that of sternite 3, 3.0 × as wide as long.

Pleon: Elevated ridges with short setae and a few scattered long setae. Tergites 2–3 with anterior and posterior transverse elevated ridges; tergite 4 with anterior transverse ridge only; tergites 5–6 smooth.

Eye: Eyestalk length about [1.1]–1.2 × broader than long, peduncle distally setose, not distinctly expanded proximally; cornea expanded distally, maximum corneal diameter 0.8–[0.9] × rostrum width, narrower than eyestalk (0.8 × maximum peduncle width).

Antennule: Article 1 slightly longer than wide, with 5 distal spines: distomesial spine well-developed; proximal lateral spine small, always present.

Antenna: Article 1 with prominent mesial process, distally falling well short or overreaching lateralmost antennular spine. Article 2 with well-developed distomesial and distolateral spines. Article 3 with distomesial spine. Article 4 unarmed.

Mxp3: Ischium with distinct distal spines on flexor and extensor margins. Merus 0.8 × length of ischium, with well-developed distal spine on extensor and flexor margins.

P1: 2.3–3.1 (males), [1.4]–2.1 (females) × carapace length; subcylindrical, spiny and with long stiff setae and iridescent setae; merus, carpus and palm with spines along mesial, dorsal and lateral surfaces, distal and mesial spines usually stronger than others. Merus [0.5]–0.9 length of carapace, 1.4–[1.6] × as long as carpus. Carpus [1.6]–2.3 × as long as wide. Palm [1.1]1.0–1.2 × carpus length, [1.7]1.6–2.2 × as long as broad. Fingers [0.7]–0.8 × palm length; fixed finger with small basal spine; movable finger unarmed.

P2–4 (P4 lost in the holotype): Stout, setose, with iridiscent setae, rugose and spinose. Meri successively shorter posteriorly: P3 merus [0.9]–1.0 × length of P2 merus, P4 merus 0.8–0.9 × length of P3 merus. P2 merus, 0.5–[0.6] × carapace length, [3.2]–3.7 × as long as broad, [1.3]1.2–1.5 × as long as P2 propodus; P3 merus 2.5–[3.2] × as long as broad, [1.1]–1.4 × as long as P3 propodus; P4 merus 2.3–2.8 × as long as broad, 0.9–1.4 × as long as P4 propodus; extensor margin of P2 and P3 with row of spines, proximally diminishing, with prominent distal spine; P4 extensor margin irregular, unarmed; flexor margin irregular,with distal spine on P2–3, distal spine absent in P4. Carpi with 1–3 spines on extensor margin on P2–3, unarmed on P4; distal spine prominent on P2–3, smaller on P4; granules below extensor margin on lateral surface of P2–4; flexor margin unarmed. Propodi stout, [4.2–4.7]3.3–5.0 × as long as broad; extensor margin irregular, armed with 2–4 spines; flexor margin with 3–6 slender movable spines in addition to distal pair. Dactyli [0.6] –0.8 × length of propodi, ending in incurved, strong, sharp spine; flexor margin with 5–6 movable spines.

Eggs: Ov. F carried approximately 7– 35 eggs of 0.3–0.5 mm diameter.

Live colour. Body brownish or dark green with small dark brown spots. P1–4 whitish, with dark brown spots and stripes.

Genetic data. COI and 16S, Table 1.

Distribution. Japan, Papua New Guinea, Vanuatu, New Caledonia, Guam Island, Northern Mariana Islands and American Samoa. Intertidal to 38 m.

Remarks. Phylladiorhynchus laureae belongs to the group of species having 2 epigastric spines, 1 hepatic spine and 3 spines on anterior branchial margin. Phylladiorhynchus laureae closely resembles to P. gustavi from French Polynesia. Both species are very similar morphologically, although very different genetically. Both species can be distinguished by the following subtle characters:

- The anterior metagastric ridge is often scale-like in P. gustavi , whereas it is continuous (holotype) or medially interrupted in P. laureae .

- The metagastric ridge is followed by a large scale in P. laureae , whereas this scale is very small or absent in P. gustavi .

- The anterior margin of thoracic sternite 3 is medially projected in P. laureae , whereas it is usually convex in P. gustavi .

Specimens of P. laureae range from 1.1 to 2.5 mm postorbital carapace length. The sequences of P. laureae (COI) were 8% divergent from P. gustavi . The five sequences of P. laureae from Guam, Japan, New Caledonia and Papua New Guinea diverged 1.8%% for COI and 0.6% for 16S.

Figures

FIGURE 26. Phylladiorhynchus laureae n. sp., A–D, F–H, holotype ovigerous female 2.4 mm (MNHN-IU-2014-13739); E, paratype male 2.0 mm (MNHN-IU-2014-13645): A, carapace and pleon, dorsal view. B, thoracic sternites 3 and 4. C, left cephalic region, showing antennular and antennal peduncles, ventral view. D, right Mxp3, lateral view. E, right P1, dorsal view. F, left P2, lateral view. G, right P3, lateral view. H, dactylus of left P2, lateral view. Scale bar: A, F–G = 1.0 mm; B–E, H = 0.6 mm.

FIGURE 27. A–C, Carapace, dorsal view; B–D, rostrum, dorsal view. A–B, Phylladiorhynchus gustavi n. sp., paratype male 2.0 mm (UF33968). C-D, Phylladiorhynchus laureae n. sp., paratype ovigerous female 2.0 mm (UF54543). Scale bars: A, C = 1 mm, B, D = 0.5 mm.

FIGURE 33. Rostrum, dorsal view. A, Phylladiorhynchus laureae n. sp., paratype female 1.7 mm (MNHN-IU-2019-2635). B, P. lini n. sp., holotype female 2.2 mm. C, P. lynceus n. sp., holotype ovigerous female 2.0 mm (MNHN-IU-2019-2593). D, P. marina n. sp., male 1.5 mm (MNHN-IU-2019-2653). E, P. medea n. sp., paratype male 2.1 mm (MNHN-IU-2014-13795). F, P. nudus Macpherson, 2008, ovigerous female 2.4 mm (WAM C46587). G, P. nui Schnabel & Ahyong, 2019, male 6.5 mm (MNHN-IU-2019-2595). H, P. orpheus n. sp., paratype male 1.9 mm (UF33962). I, P. paula n. sp., paratype male 2.3 mm (MNHN-IU-2019-2699). J, P. penelos n. sp., paratype male 3.3 mm (UF1224). K, P. pepei n. sp., holotype male 3,2 mm (MNHN-IU-2016-486). L, P. phanus n. sp., paratype male 2.1 mm (MNHN-IU-2019-2687). Scale bars = 1 mm.