Phylladiorhynchus gustavi Rodríguez-Flores &amp; Macpherson &amp; Machordom 2021, n. sp.
Creators: name: Rodríguez-Flores, Paula C.
name: Macpherson, Enrique
name: Machordom, Annie
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Galatheidae
Phylladiorhynchus
Phylladiorhynchus gustavi

description: <i>Phylladiorhynchus gustavi</i> n. sp. (Figs. 14, 21B, 27A–B, 54D) <b>Type material.</b> <i>Holotype.</i> French Polynesia. Society Islands, Moorea Island, NE of Tareu Pass, 17.4836°S, 149.8581°W, 22 m, 24 July 2006: ov. F 2.2 (UF9766). <i>Paratypes.</i> Cook Islands. Rarotonga Island, Matavera, 21.226°S, 159.7293°W, 9–24 m, 26 June 2006: 1 ov. F 2.0 mm (UF9232). French Polynesia. Society Islands. Moorea Is. 17.506°S, 149.759°W, 15–22 m, 27 May 2006: 1 ov. F 1.8 mm (UF9471), 1 ov. F 2.0 (UF9603).— 17.4836°S, 149.8581°W, 22 m, 24 July 2006: 1 M 1.7 (UF9756).— 17.4768°S, 149.8327°W, 5 August 2006: 2 M 1.0– 2.2 mm, 1 ov. F 2.1 mm (UF14832).— 17.4764°S, 149.8327°W, 4–7 m, 10 November 2008: 1 M 2.3 mm (UF16338), 1 ov. F 2.3 mm (UF16370), 1 M 2.4 mm, 1 ov. F 2.1 mm, 1 F 1.7 mm (UF18384), 1 M 2.4 mm (UF16399).— French Polynesia. BENTHAUS Stn DW1926, 24.6360°S, 146.0136°W, 50–90 m, 13 November 2002: 1 M 2.2 mm, 1 ov. F 2.6 mm (MNHN- IU-2019-2592). <b>Other material</b>. French Polynesia. Society Islands. Moorea Is. Maharepa, 2 m, 11 October 2008: 1 ov. F 2.3 mm (UF15431).— on <i>Pocillopora</i>, June 2009: 1 M 2.0 mm (UF37850).— 17.484°S, 149.9264°W, 19–20 m, 3 November 2009: 1 M 1.8 mm (UF23879).— 17.4756°S, 149.8425°E, 13–17 m, 5 December 2009: 1 ov. F 2.2 mm (UF24183).— 17.4764°S, 149.8316°W, 13 m, 31 January 2012: 4 M 1.4–2.1 mm, 9 ov. F 1.7–2.1 mm, 2 F 1.2–1.9 mm (UF33774).— 17.4759°S, 149.8419°W, 13 m, 4 February 2012: 10 M 1.4–2.3 mm, 9 ov. F 1.6–2.3 mm, 1 F 1.9 mm (UF33968), 1 F 2.2 mm (UF33966), 1 M 2.0 mm (UF33967). Gambier Islands. Totegegie Airport, 23.0776°S, 134.8884°W, 22.5 m, 6 February 2013: 1 ov. F 2.3 mm (UF35486), 1 M 2.2 mm (UF35473), 1 F 1.8 mm (UF35479), 1 ov. F 2.5 mm (UF35481), 1 M 2.3 mm (UF35485). <b>Etymology.</b> The new species is named after our colleague Gustav Paulay from the Florida Museum of Natural History for his valuable contribution to marine research. <b>Description.</b> <i>Carapace</i>: Slightly broader than long; transverse ridges with dense short setae and long and thick iridescent setae. Gastric region slightly convex with some transverse ridges: epigastric ridge distinct with 2 spines, short scales laterally; anterior protogastric ridge not medially interrupted, nearly extending laterally to carapace margin, sometimes followed by small scales; anterior mesogastric ridge not medially interrupted, laterally continuing to first branchial spine, sometimes followed by some short lateral scales; anterior metagastric ridge scalelike, often followed by some short small median scale posteriorly. Mid-transverse ridge not interrupted, medially depressed, cervical groove indistinct, followed by 2 not interrupted or minutely interrupted ridges, interspersed with 1 short lateral ridge and few short scales. Lateral margins slightly convex, with 6–7 distinct spines: first anterolateral spine well-developed, reaching anteriorly to 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 0.2–[0.3] that of carapace; lateral margins serrated and strongly convex, with well-developed supraocular basal spines and small subapical spines (tridentiform). Pterygostomian flap ending in blunt tooth, upper margin smooth. <i>Thoracic sternum</i>: As wide as long. Sternite 3 moderately broad, 1.8–[1.9] × as wide as long, anterior margin serrated and convex, anterolaterally rounded. Sternite 4 widely contiguous to sternite 3; anterolaterally serrated, surface depressed in midline, smooth; greatest width [3.3] × that of sternite 3, [2.5] × as wide as long. <i>Pleon</i>: 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. <i>Eye:</i> Eyestalk length about 1.0–[1.1] × broader than long, peduncle distally setose, not distinctly expanded proximally; cornea expanded distally, maximum corneal diameter [0.6]–0.7 × rostrum width, narrower than eyestalk (0.8–0.9 maximum peduncle width). <i>Antennule</i>: Article 1 slightly longer than wide, with 4 distal spines: distomesial spine well-developed; proximal lateral spine always absent. <i>Antenna:</i> 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. <i>Mxp3:</i> Ischium with distinct distal spines on flexor and extensor margins. Merus 0.7–[0.8] × length of ischium, with well-developed distal spine on extensor and flexor margins. <i>P1</i>: [2.8]–3.0 (males), 1.9–2.0 (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 0.7–[1.0] length of carapace, [1.6]–1.9 × as long as carpus. Carpus [1.5]–1.7 × as long as wide. Palm [1.1]–1.2 × carpus length, [1.5]–1.6 × as long as broad. Fingers 0.8 × palm length fixed finger with 2 small basal spines, movable finger with basal spine or unarmed. <i>P2–4</i>: Stout, setose, with iridiscent setae, and spinose. Meri successively shorter posteriorly: P3 merus 0.9 × length of P2 merus, P4 merus [0.8]–0.9 × length of P3 merus. P2 merus, [0.7]–0.9 × carapace length, 3.1–[3.4] × as long as broad, 1.1–[1.2] × as long as P2 propodus; P3 merus 3.4–[3.8] × as long as broad, 1.1–[1.2] × as long as P3 propodus; P4 merus 3.2 × as long as broad, 1.0–1.1 × 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, [4.0]3.6–4.3 × 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]–0.7 × length of propodi, ending in incurved, strong, sharp spine; flexor margin with 5–6 movable spines. <i>Eggs</i>: Ov. F carried approximately 8– 20 eggs of 0.4–0.6 mm diameter. <b>Live colour.</b> Base colour of carapace and pleon whitish or beige, with small brownish patches. P1 whitish or beige with scattered brownish spots. P2–4 whitish, with brown bandings. <b>Genetic data.</b> COI, Table 1. <b>Distribution.</b> French Polynesia, Society Islands and Cook Islands, between 2 and 90 m. <b>Remarks.</b> <i>Phylladiorhynchus gustavi</i> belongs to the group of species having 2 epigastric spines, 1 hepatic spine and 3 spines on anterior branchial margin. The specimens range from 1.2 to 2.6 mm postorbital carapace length. The closest species is <i>P. laureae</i>, from from Japan, Mariana Islands, American Samoa, Papua New Guinea, Vanuatu and New Caledonia (see the differences under the Remarks of that species). The two sequences of <i>P. gustavi</i> from French Polynesia diverged 0.4% for COI.
description: Published as part of <i>Rodríguez-Flores, Paula C., Macpherson, Enrique &amp; Machordom, Annie, 2021, Revision of the squat lobsters of the genus Phylladiorhynchus Baba, 1969 (Crustacea, Decapoda, Galatheidae) with the description of 41 new species, pp. 1-159 in Zootaxa 5008 (1)</i> on pages 41-42, DOI: 10.11646/zootaxa.5008.1.1, http://zenodo.org/record/5157455