Phylladiorhynchus janiqueae, 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 : 59-62

Phylladiorhynchus janiqueae n. sp.

( Figs. 21H , 22 , 54E )

Records requiring verification:

Phylladiorhynchus serrirostris . — Tirmizi & Javed, 1980: 260, fig. 3 ( Mozambique Channel, off South Africa, off Somalia, Andaman Sea).

Phylladiorhynchus integrirostris . — Tirmizi & Javed, 1993: 33, fig. 15 ( Mozambique Channel, off South Africa, off Somalia, Andaman Sea).

Type material. Holotype. Madagascar, ATIMO VATAE Stn TB 01, 24.9966°S, 47.0950°E, 22 m, 30 April 2010: M 2.3 mm (MNHN-IU-2014-13799).

Paratypes. Madagascar. ATIMO VATAE Stn CP 3511, 25.2500°S, 47.2416°E, 97–98 m, 29 April 2010: 1 F 2.0 mm (MNHN-IU-2010-2750).— Stn TB 02, 25.0216°S, 47.0083°E, 18 m, 1 May 2010: 1 M 2.7 mm (MNHN- IU-2016-462).— Stn DW 3530, 24.5983°S, 47.5350°E, 80–86 m, 2 May 2010: 1 M 2.5 mm (MNHN-IU-2016- 485).— Stn CP 3546, 25.3783°S, 46.7083°E, 84–85 m, 4 May 2010: 1 M 2.2 mm (MNHN-IU-2016-483), 1 M 1.7 mm (MNHN-IU-2014-13800).— Stn CP 3579, 25.9083°S, 45.5533°E, 65–66 m, 9 May 2010: 1 M 2.1 mm (MNHN- IU-2016-464).— Stn DW 3605, 25.9083°S, 44.8500°E, 56–57 m, 13 May 2010: 2 M 2.3–2.5 mm (MNHN-IU-2016- 484).— Stn CP 3624, 25.6350°S, 45.9500°E, 63– 63 m, 15 May 2010: 1 M 1.8 mm (MNHN-IU-2016-482) .

Other material. SW Indian Ocean. MD08 Stn DC32, 33.8333°S, 43.1833°E, 40–43 m, 15 March 1976: 1 ov. F 3.0 mm (MNHN-IU-2016-467).—Stn CC31 St 6, 33.1666°S, 43.8666°E, 36–47 m, 15–16 March 1976: 1 M 2.5 mm, 1 ov. F 2.4 mm (MNHN-IU-2016-481).—Stn DC33, 33.8333°S, 43.1833°E, 25–30 m, 16 March 1976: 1 M 2.8 mm (MNHN-IU-2016-466).

Reunion Island. MD32 Stn CP 43, 21.3450°S, 55.4483°E, 73–77 m, 18 August 1982: 5 M 1.5–2.3 mm, 5 ov. F 1.8–2.3 mm, 4 F 1.5–1.8 mm (MNHN-IU-2019-2696) .

SW Indian Ocean. Walters Shoal-MD208 Stn WS03, 33.2033°S, 43.8466°E, 40 m, 30 April 2017: 1 F 1.4 mm (MNHN-IU-2016-455), 7 M 1.4–2.1 mm, 8 F 1.4–2.2 mm, 4 postlarvae 1.0– 1.1 mm (MNHN-IU-2016-459).—Stn WB05, 33.2516°S, 43.9083°E, 26–30 m, 1 May 2017: 4 M 1.5–1.8 mm, 8 F 1.2–2.2 mm, 3 postlarvae 1.0– 1.1 mm (MNHN-IU-2016-456), 6 M 1.7–2.7 mm, 1 ov. F 2.5 mm, 4 F 1.4–1.6 mm (MNHN-IU-2016-458), 1 M 2.2 mm (MNHN-IU-2014-12606), 1 M 1.9 mm (MNHN-IU-2014-13841).—Stn WS06, 33.2516°S, 43.9083°E, 26 m, 1 May 2017: 1 M 1.9 mm, 2 F 1.2–1.3 mm (MNHN-IU-2017-3613).—Stn WS07, 33.2566°S, 43.8700°E, 30–33 m, 2 May 2017: 3 M 1.3–1.7 mm, 3 F 1.3–1.9 mm (MNHN-IU-2016-487).—Stn WS08, 33.2283°S, 43.9316°E, 30–33 m, 3 May 2017: 1 M 1.8 mm (MNHN-IU-2014-13840), 2 M 1.3–2.2 mm, 5 F 1.3–2.3 mm (MNHN-IU-2017-3333),

9 M 1.3–2.1 mm, 7 F 1.2–2.2 mm, 11 postlarvae 1.0– 1.1 mm (MNHN-IU-2016-460).—Stn WB09, 33.2300°S, 43.9300°E, 27–30 m, 4 May 2017: 16 M 1.2–3.1 mm, 15 F 1.4–2.2 mm, 7 postlarvae 1.0– 1.1 mm (MNHN-IU- 2014-13839), 1 postlarvae 1.0 mm (MNHN-IU-2016-457), 1 F 1.3 mm (MNHN-IU-2017-2960), 2 M 2.1–2.4 mm, 4 F 1.5–2.1 mm, 10 postlarvae, 0.9–1.0 mm (MNHN-IU-2017-3316).—Stn WB10, 33.1516°S, 43.8633°E, 30 m, 6 May 2017: 26 M 1.5–2.1 mm, 25 F 1.2–2.5 mm, 14 postlarvae 1.0– 1.2 mm (MNHN-IU-2019-2689), 13 M 1.1–2.4 mm, 15 F 1.1–2.3 mm, 3, postlarvae 1.0– 1.1 mm (MNHN-IU-2017-3812), 1 M 2.4 mm (MNHN-IU-2014-12639), 2, postlarvae, 1 broken (MNHN-IU-2017-2990).

Etymology. The new species is named after Janique Etienne, Senior Officer in charge of High Seas projects with Fonds Français pour l’Environnement Mondial (FFEM), in recognition for her support to the Walters Shoals expedition.

Description. Carapace: [0.9]–1.1 × as long as broad; transverse ridges with dense short setae and few scattered long and thick iridescent setae. Gastric region with 4 transverse ridges: epigastric ridge distinct with 2 median spines; anterior protogastric ridge not medially interrupted, nearly extending laterally to carapace margin; anterior mesogastric ridge not medially interrupted, laterally continuing to first branchial spine; anterior metagastric ridge scale-like (rarely medially interrupted), sometimes followed by a short small scale. Mid-transverse ridge not interrupted, medially slightly 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 4–5 branchial spines (3 anterior and 1–2 posterior). Rostrum leaf-like, horizontal, dorsally convex, [1.4]–1.6 × as long as broad, length 0.4 and breadth 0.3 that of carapace; lateral margins smooth or minutely serrated and convex, with well-developed supraocular basal spines and small subapical spines. Pterygostomian flap ending in anterior spine, upper margin smooth.

Thoracic sternum: As wide as long. Sternite 3 moderately broad, 1.9–[3.0] × as wide as long, anterior margin slightly convex or straight. Sternite 4 widely contiguous to sternite 3; anterolaterally smooth, surface depressed in midline, smooth; greatest width 2.0–[2.5] × that of sternite 3, 2.7–[3.5] × as wide as long.

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

Eye: Eyestalk length about1.1 × broader than long, peduncle distally setose, not distinctly expanded proximally; cornea expanded distally, maximum corneal diameter 0.9 × rostrum width, as wide as eyestalk.

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 of lateralmost antennular spine. Article 2 with well-developed distomesial and distolateral spines. Article 3 with distomesial spine and distolateral spines, otherwise only distomesial spine. Article 4 unarmed.

Mxp3: Ischium with distinct distal spines on flexor and extensor margins. Merus 0.6–[0.8] × length of ischium, with well-developed distal spine on extensor and flexor margins.

P1: 2.0–[3.0] (males), 1.7–1.9 (females) × carapace length; subcylindrical, spiny and with dense long stiff setae; merus, carpus and palm with spines along mesial, dorsal and lateral surfaces, distal and mesial spines usually stronger than others. Merus 0.7–[1.1] length of carapace, 1.7–[1.8] × as long as carpus. Carpus [1.5]–2 × as long as wide. Palm 1.1 × carpus length, [1.4]–1.7 × as long as broad. Fingers [0.9]0.8–1.0 × palm length; fixed finger with 2 small basal spines; movable finger with 1–2 basal spines or unarmed.

P2–4: stout, setose 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–[0.7] × carapace length, 3.8–[4.0].times as long as broad, 1.0–[1.4] × as long as P2 propodus; P3 merus 3.2–[3.9] × as long as broad, 1.1–[1.3] × as long as P3 propodus; P4 merus [3.3]2.9–3.6 × 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, P4 lateral surface with median row of 2 small spines, absent in P2–3. 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, [4.3–4.6]3.7–4.4 × as long as broad; extensor margin irregular, armed with 2–4 spines on proximal half, otherwise unarmed; flexor margin with 3–4 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.

Eggs: Ov. F carried approximately 20– 35 eggs of 0.4–0.5 mm diameter.

Live colour. Body uniformly pale orange with subtle pattern of darker orange patches; transverse orange bar across base of rostrum and ocular peduncle. P1 light orange with scattered reddish spots. P2–4 whitish or translucent, with orange bands.

Genetic data. COI and 16S, Table 1.

Distribution. South West Indian Ocean, Madagascar, Reunion Island and Walter Shoals from 18 to 98 m.

Remarks. Phylladiorhynchus janiqueae belongs to the group of species having 2 epigastric spines, 1 hepatic spine, 3 spines on the anterior branchial margin and the pleonal tergite 3 with the anterior ridge only. This species fits with the illustrations from Tirmizi & Javed (1980, 1993) from the Indian Ocean, however we have not examined this material, therefore the identification of these specimens remains dubious. The new species is closely related with P. medea from French Polynesia and New Caledonia (see the differences under the Remarks of this species).

The specimens of P. janiqueae range from 1.0 to 3.0 mm postorbital carapace length. The four sequences of P. janiqueae from Madagascar and Walter Shoal diverged 0% for COI and 0% for 16S.

Figures

FIGURE 21. Rostrum, dorsal view. A, Phylladiorhynchus euryalus n. sp., paratype male 1.8 mm (UF34732). B, P. gustavi n. sp., paratype male 1.7 mm (UF9756). C, P. heptacanthus n. sp., holotype female 2.1 mm (MNHN-IU-2017-2534). D, P. hylas n. sp., paratype female 1.6 mm (MNHN-IU-2016-495). E, P. integrirostris (Dana, 1852), male 1.6 mm (UF15285). F, P. integrus (Benedict, 1902), ovigerous female 3.2 mm (MNHN-IU-2014-13853). G, P. iphiclus n. sp., holotype ovigerous female 2.3 mm (MNHN-IU-2019-2662). H, P. janiqueae n. sp., paratype male 1.8 mm (MNHN-IU-2016-482). I, P. jeffkinchi n. sp., paratype male 2.7 mm (MNHN-IU-2014-13565). J, P. joannotae n. sp., paratype male 2.1 mm (MNHN-IU-2014-20055). K, P. joannotae n. sp., holotype ovigerous female 2.1 mm (MNHN-IU-2014-13805). L, P. koumac n. sp., paratype male 1.5 mm (MNHN-IU- 2014-20121). Scale bars: 1 mm.

FIGURE 22. Phylladiorhynchus janiqueae n. sp., holotype male 2.3 mm (MNHN-IU-2014-13799): 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, right P2, lateral view. G, right P3, lateral view. H, right P4, lateral view. I, dactylus of right P2, lateral view. Scale bar: A, E–H = 1.0 mm; B–D, I = 0.6 mm.

FIGURE 54. Colour in life, dorsal view. A. Phylladiorhynchus acastus n. sp. Papua New Guinea, male 2.5 mm (MNHN-IU- 2014-10017). B, Phylladiorhynhus barbeae n. sp. Papua New Guinea, paratype male 1.6 mm (MNHN-IU-2014-13810). C, Phylladiorhynhus barbeae n. sp. Papua New Guinea, male 2.5 mm (MNHN-IU-2014-13813). D, Phylladiorhynchus gustavi n. sp. French Polynesia, male 2.3 mm (UF16338). E, Phylladiorhynchus janiqueae n. sp. Walter shoal, male 1.8 mm (MNHN-IU- 2014-13840). F, Phylladiorhynchus jeffkinchi n. sp. Papua New Guinea, ovigerous female 2.2 mm (MNHN-IU-2014-2176). G, Phylladiorhynchus joannotae n. sp. French Polynesia, ovigerous female 2.2 mm (UF15544). H, Phylladiorhynchus joannotae n. sp. New Caledonia, female 1.0 mm (MNHN-IU-2014-20147). I, Phylladiorhynchus koumac n. sp. New Caledonia, male 1.5 mm (MNHN-IU-2014-20121).