Uroptychus nicoleae Wicksten & Conway 2023, new species
Creators: name: Wicksten, Mary K.
name: Conway, Kevin W.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Chirostylidae
Uroptychus
Uroptychus nicoleae

description: Uroptychus nicoleae, new species
(Figs. 1–4)
Material examined.— Holotype female, carapace length 9.3 mm, width 9.5 mm. San Clemente Escarpment, 32.679°N, 118.123°W, 1177.661 m, on antipatharian Lillipathes sp. (sample NA 124–194), 4 Nov. 2020, ROV Hercules, E.V. Nautilus; Scripps Institution of Oceanography SIO-BIC C14476, NA20-155. Paratype male, carapace length 6.1mm, width 5.9 mm, with female at same collection site, SIO-BIC C14914.
Description. Carapace (Fig. 2 A) 1.1 times as long as wide, widest at posterior branchial region. Row of 15 spinules of different sizes across gastric region of carapace. Antennal spine short.
Anterolateral tooth prominent, acute, directed forward, overreaching antennal spine. Two sharp isolated teeth posterolateral to anterolateral tooth, series of 3 smaller teeth and spinules extending posteriorly to widest margin of carapace. Rostrum elongate triangular, smooth, 2 times as long as wide, female with tooth at 0.2 length from apex on right side and at 0.3 length from apex on left side, 2 small teeth posterior to it on right side, apex broken. Male with rostrum acute, 2 lateral spines on each side, spines on right side arranged slightly proximal to those on left side.
Pterygostomian flap (Fig. 2 D) anteriorly angular, with 6 small spines: 1 single anterior spine, middle row of 3 and posterior row of 2 spines.
Sternum (Fig. 2 B) anteriorly concave, plastron 0.5 times as long as width at sternite 4. Sternite 3 with deep notch in anterior margin, 2 blunt teeth on either side of notch, anterolateral angle produced. Sternite 4 length of anterolateral margin 0.9 times length of posterolateral margin, the latter forming a strong triangular process. Sternites 5–6 considerably smaller than sternite 4. Sternite 6 with 2 blunt marginal teeth. Sternite 7 reduced. Posterior margin of sternum almost straight. Somites of abdomen smooth, without dorsal spines. Lateral margins pointed. Pleopods setose. Telson (Fig. 2 C) 2.7 times wider than long, with median groove. Exopod of uropods with longitudinal ridge. Female carried 5 eggs. Eye reaching 0.3 times length of rostrum, pigmented, cornea 0.6 times length of eyestalk. Antennule (Fig. 2 E) with peduncle unarmed. Flagella unequal, densely setose. Antenna (Fig. 2 F) with acute stylocerite overreaching antennal peduncle, the latter shorter than rostrum. Flagellum broken.
Third maxillipeds (Fig. 2 G) with bases separated by triangular anterior end of excavated sternum. Ischium with 3 blunt teeth on crista dentata, flexor margin rounded distally. Merus 1.2 times as long as ischium, without teeth, with a tuft of setae; distal segments heavily setose.
First pereopod (Figs. 3 A, B) ischium with sharp laterodistal spine, interior margin with large subterminal tooth flanked by 2 smaller teeth, 5 teeth decreasing in size proximally. Merus 4.2 times as long as wide, with large teeth at distal margin, large anterior tooth followed by smaller but acute tooth, single tooth spaced separately from anterior and posterior teeth, followed by 3 spinules and row of 5 widely spaced teeth on lateral margin, 5 teeth of similar size on mesial margin.
Carpus 4.6 times as long as wide with 2 large marginal teeth at junction with propodus, 2 smaller teeth between them, row of 6 small, blunt lateral teeth. Propodus 9 times as long as wide, with row of 5 coarse setae on dorsal margin. Fingers of chela 2.7 times length of palm. Dactyl curved, with row of small spinules, immovable finger of chela with setae.
Second to fourth pereopods (Fig. 3 C) similar in shape but decreasing in length from anterior to posterior. Second pereopod merus without teeth on dorsal surface, large mesodistal tooth on carpus, propodus with 4 spines at margin with dactyl, dactyl curved, with acute apex and 8 large spines. Third pereopod with 2 faint dorsal teeth, one sharp tooth each on dorsal and ventral margins of merus, carpus without teeth, propodus with 5 spines at distomesial border, dactyl curved and bearing 6 heavy teeth blunt spines.
Fourth pereopod with one distal tooth on merus, no teeth on carpus, propodus with 4 anterior movable spines. Dactyl (Fig. 3 D) curved, with large apical spine followed by 8 movable spines, decreasing in size from apex proximally, at oblique angle to axis of dactyl.
Color in life. Anterior carapace red, pink to cream posteriorly; chelipeds and walking legs pink (Fig. 4).
Habitat. Clinging to branch of antipatharian Lillipathes sp. (SIO-BIC Co3558) on steep vertical cliff.
Genetic Distances. DNA extraction, amplification, and sequencing methods for mitochondrial cytochrome c oxidase subunit I (CO1) were exactly as in Hatch et al. (2020). We examined a 680bp sequence of the cytochrome C oxidase I (COI) gene obtained from the holotype of U. nicoleae sp.nov. (Genbank number GB# ON357596). The uncorrected p -distance between this sequence and those obtained from the putative close relatives U. macquariae Schnabel, Burghart & Ahyong, 2017 (n = 3, GB# MG029533-35) and U. insignis (n = 1, GB# MG029532), are 2.2% and 8.1%, respectively. The uncorrected p -distance between the COI sequence of U. nicoleae sp.nov. and that of the geographically close congener, U. bellus (n = 1, GB# ON715941), is 15.9%.
Etymology. Named in honor of Nicole Reinault of the Ocean Exploration Trust, lead biologist on cruises of the Nautilus and an enthusiast of deep-sea biology. A noun in the genitive.
description: Published as part of Wicksten, Mary K. & Conway, Kevin W., 2023, The Chirostyloidea of the Northeastern Pacific: Host Associations, Range Extensions and a New Species (Decapoda: Anomura, pp. 167-176 in Zootaxa 5284 (1) on pages 168-172, DOI: 10.11646/zootaxa.5284.1.7, http://zenodo.org/record/7919091