Phylladiorhynchus bahamut Rodríguez-Flores & Macpherson & 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 bahamut

description: Phylladiorhynchus bahamut n. sp.   
(Figs. 6, 11G)  
 Phylladiorhynchus integrirostris.— Lewinsohn, 1982: 295, fig. 1 (Gulf of Aqaba, N Red Sea).   
 Type material. Holotype. Saudi Arabia, Yanbu, Ras Majiz, highly dissected reef, 38.2761°N, 23.7725°E, 4–8 m, 3 March 2014: M 2.5 mm (UF40205).   
 Etymology. From Bahamut, a Persian sea monster supporting the structure that holds up the earth. The name is a substantive in apposition.   
 Description. Carapace: As long as or slightly longer than broad; transverse ridges with dense short setae and some scattered iridescent thick long setae. Gastric region slightly convex with 4 transverse ridges: epigastric ridge distinct with 2 median spines, short scales laterally; 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 not medially interrupted, followed by median scale. 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 convex, with 5 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 3 branchial spines (2 anterior and 1 posterior). Rostrum leaf-like, horizontal, dorsally slightly concave, [1.4] × as long as broad, length [0.4] and breadth [0.2] that of carapace; lateral margins minutely serrated and convex, with well-developed supraocular basal spines, subapical spines absent. Pterygostomian flap ending in sharp tooth, upper margin smooth.   
 Thoracic sternum: As wide as long. Sternite 3 moderately broad, [1.7] × as wide as long, anterior margin serrated and convex, with a median projection. Sternite 4 widely contiguous to sternite 3; anterolaterally serrated, surface flattish, smooth; greatest width [3.2] × that of sternite 3, [2.9] × as wide as long.   
 Pleon: Elevated ridges with short setae and a few scattered long setae. Tergite 2 with anterior and posterior transverse elevated ridges; tergites 3–4 with anterior transverse ridge only; tergites 5–6 smooth.   
 Eye: Eyestalk length about [1.1] × broader than long, peduncle distally setose, not distinctly expanded proximally; cornea expanded distally, posterior margin irregular, maximum corneal diameter [1.1] × rostrum width, as wide as or wider than eyestalk.   
 Antennule: Article 1 slightly longer than wide, with 5 distal spines: distomesial spine well-developed; proximal lateral spine small, obsolescent.   
 Antenna: Article 1 with prominent mesial process, nearly reaching end of lateralmost antennular spine. Article 2 with well-developed distomesial and distolateral spines. Articles 3 and 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: [3.3] (male) × carapace length; subcylindrical, spiny and with long stiff setae, without plumose setae; merus, carpus and palm with spines along mesial, dorsal and lateral surfaces, distal and mesial spines usually stronger than others. Merus [1.1] length of carapace, [1.6] × as long as carpus. Carpus [1.8] × as long as wide. Palm [1.3] × carpus length, [2.1] × as long as broad. Fingers [0.7] × palm length; fixed finger unarmed; movable finger with small basal spine.   
 P2–4: Slender, densely setose and spinose. Meri successively shorter posteriorly: P3 merus [0.9] × length of P2 merus; P4 merus [0.9] × length of P3 merus. P2 merus [4.7] × as long as broad, [1.3] × as long as P3 propodus; P3 merus [3.4] × as long as broad, [1.2] × as long as P3 propodus; P4 merus [3.6] × as long as broad, [1.1] × as long as P4 propodus; extensor margin of P3 with row of spines, proximally diminishing, with prominent distal spine; P4 extensor margin irregular, unarmed; flexor margin irregular, with distal spine on P3, distal spine absent in P4. Carpi with 1–3 spines on extensor margin on P3, unarmed on P4; distal spine prominent on P3, smaller on P4; granules below extensor margin on lateral surface of P3–4; flexor margin unarmed. Propodi stout, [4.5–4.6] × as long as broad; extensor margin irregular, armed with 2–4 spines; flexor margin with 3–4 slender movable spines in addition to distal pair. Dactyli [0.6] × length of propodi, ending in incurved, strong, sharp spine; flexor margin with 4 movable spines.   
 Eggs: No data.   
 Live colour. Unknown.   
 Genetic data. COI and 16S, Table 1.   
 Distribution. Red Sea, from 4 to 8 m.   
 Remarks. Phylladiorhynchus bahamut agrees with the species recorded and illustrated by Lewinsohn (1982) from the Gulf of Aqaba, who also pointed out that it might be a different species than P. integrirostris. Phylladiorhynchus bahamut belongs to the group of species having 2 median epigastric spines, the hepatic margin with a small spine and 2 spines on the anterior branchial margin. The closest species is P. peneleos (see the differences under the Remarks of this species).
description: Published as part of 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, pp. 1-159 in Zootaxa 5008 (1) on pages 23-24, DOI: 10.11646/zootaxa.5008.1.1, http://zenodo.org/record/5157455