Janetogalathea californiensis ( Benedict, 1902 )

Rodríguez-Flores, Paula C., Seid, Charlotte A., Rouse, Greg W. & Giribet, Gonzalo, 2023, Cosmopolitan abyssal lineages? A systematic study of East Pacific deep-sea squat lobsters (Decapoda: Galatheoidea: Munidopsidae), Invertebrate Systematics 37 (1), pp. 14-60 : 21-24

Janetogalathea californiensis ( Benedict, 1902)

family Munidopsidae stat. nov.

( Fig. 5 a, b .)

Galathea californiensis Benedict, 1902

Material examined

Non-type specimens. USA: off San Diego, California, leg. Harim Cha, Kent Trego, R/V New Horizon student cruise; 28.x.2007, 32.67500°N, 117.36330°W, 175–300 m: 1 M 24.1 mm, 1 F 14.9 mm (SIO-BIC C11027). — USA: Crespi Knoll, off California, leg. Emily McLaughlin, Jessica Pruitt, R/V Falkor, ROV SuBastian dive S0169 Slurp 2, 13.x.2018, 33.09770°N, 117.86790°W, 484.2 m: 1 F 5.5 mm (SIO-BIC C14023). — USA: California, leg. E/V Nautilus, ROV Hercules dive H1534, Stn NA074-027-01, 14.vii.2018, 33.95930°N, 119.47540°W, 172.4 m: 1 F 9.5 mm (MCZ IZ-139642).

Diagnosis

Modified from Macpherson and Baba (2011). Carapace with transverse striae usually granulated with numerous short

setae and scattered stiff long setae, laterally with 4–6 spines, cervical grooves distinct. Rostral spine flattish, subtriangular, lateral margin usually with 3–4 lateral spines, proximal small. With a pair of epigastric spines. Frontal margins slightly oblique. Orbit not distinctly excavated, without outer orbital angle. Anterolateral spine of carapace strong. Branchial margin with 4 spines. Abdominal somites 2–4 with 2 transverse ridges, unarmed. Telson incompletely subdivided. Sternite 3 narrow, expanded laterally, sternite 4 subtriangular. Eyes large, movable, cornea strongly dilated. Article 1 of antennule

with 3 well-developed spines. Article 1 of antenna with distomesial spines short, fused with orbit. Short and thick flagellum on Mxp1. Mxp3 merus as long as ischium, subrhomboidal in lateral view. P1 slender, elongate. P2–4 long and slender; dactyli slender, curving, flexor margin with spine-like setae. Epipods absent from all pereopods.

Colouration

Carapace and abdomen reddish or light orange. P1–4 light orange.

Distribution

Baja California, Gulf of California, Mexico Channel Islands, California, USA. From 89- to 3993-m depth (see comments in Hendrickx 2021 and Hendrickx et al. 2011, regarding J. californiensis geographic distribution).

Genetic data

COI, 16S rRNA and 28S rRNA.

Remarks

Janetogalathea californiensis is now included in the family Munidopsidae due to evidence from molecular phylogenetics placing this as sister group of Leiogalathea , according to nuclear and mitochondrial data. We investigated the presence of the chief synapomorphy of Munidopsidae , the absence of a short or reduced flagellum on the exopod of the Mxp1. The Mxp 1 exopod presents a short, thick pseudoflagellum, as in Leiogalathea ( Ahyong et al. 2010) . However, the validity of this character as a synapomorphy for Munidopsidae is questionable. Both Leiogalathea and Janetogalahea also share the presence of a broad triangular or subtriangular rostrum, a well-developed cornea and a carapace with few to several transverse setose striae. Janetogalathea and Leiogalathea could arguably form a clade that could be assigned family rank, showing morphological convergence with squat lobsters in the family Galatheidae but this will be addressed in future studies.

The wide bathymetric distribution and dubious morphological identification of specimens from the Galapagos Islands ( Arnés-Urgellés et al. 2020; Hendrickx 2021) suggest that Janetogalathea californiensis could constitute a species complex. A deeper study including genetic data across the species range should be conducted to test this hypothesis.

Figures

Fig. 5. Janetogalathea californiensis (Benedict, 1902). (a) Mxp1, lateral view, California (MCZ IZ-139642). (b) General habitus, dorsal view, 1 M (SIC BIO C11027) San Diego, CA, USA.