Uroptychus nanophyes McArdle 1901
Creators: name: Baba, Keiji
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Chirostylidae
Uroptychus
Uroptychus nanophyes

description: Uroptychus nanophyes McArdle, 1901
Figures 158, 159, 305H
Uroptychus nanophyes McArdle, 1901: 525. — Alcock & McArdle 1902: pl. 57, figs 1, 1a. — Van Dam 1940: 96, fig. 1. — Baba 2005: 48, 228, fig. 16.
— Poore et al. 2011: 329, pl. 7, fig. A.
Not Uroptychus nanophyes — Baba 1981: 117, fig. 5 (nr. U. sexspinosus Balss,1913a).
TYPE MATERIAL — Syntypes: India, NE coast of Sri Lanka, 926 m (ZSIC). [not examined].
MATERIAL EXAMINED — Vanuatu. MUSORSTOM 8 Stn CP982, 19°21.80’S, 169°26.47’ E, 408-410 m, 23.IX.1994, 1 ov. ♀ 5.7 mm (MNHN- IU-2014-16744). – Stn CP1026, 17°50.35’S, 168°39.33’E,437-504 m, 28.IX.1994, 1 ♂ 4.2 mm (MNHN-IU-2014-16745). New Caledonia, Loyalty Ridge. MUSORSTOM 6 Stn DW420, 20°29.27’S, 166°43.35’ E, 600 m, on a species of Primoidae (Alcyonacea), 16.II.1989, 3 ♂ 6.9-7.9 mm, 2 ♀ 5.5, 7.2 mm, 3 spec. (sex indet.) 2.7-3.1 mm (MNHN-IU-2014-16746). New Caledonia, Hunter and Matthew Islands. VOLSMAR Stn DW05, 22°26’ S, 171°46’E, 620- 700 m, 01.VI.1989, 2 ♂ 8.8, 9.1 mm, 2 ♀ 5.1 mm, carapace broken (MNHN-IU-2014-16747). New Caledonia, Norfolk Ridge. CHALCAL 2 Stn CC01, 24°55’S,168°22’E,500-580 m,28.X.1986,2 ov.♀ 4.3,6.5 mm (MNHN-IU-2014-16748). – Stn CP25,23°38.6’S,167°43.12’E,418 m, 30.X.1986,1 ♂ 5.3 mm (MNHN-IU-2014-16749). – Stn CP26, 23°18.15’S, 168°03.58’E, 296 m, 3.X.1986, 2 ♂ 8.7, 11.7 mm (MNHN-IU-2014-16750). – Stn DW76, 23°40.5’ S, 167°45.2’E, 470 m, on Primoidae gen. sp. (Alcyonacea), 30.X.1986, 1 ♂ 11.3 mm (MNHN-IU-2014-16751), 1 ov. ♀ 10.3 mm (MNHN-IU-2014-16752). AZTÈQUE Stn CH 06, 23°37.9’S, 167°42.5’E, 425-470 m, 14.II.1990, 5 ♂ 9.2-11.8 mm, 4 ov. ♀ 10.3-11.1 mm (MNHN-IU-2014-16753). SMIB 2 Stn DW13, 22°52’S, 167°13’E, 427-454 m, 18.IX.1986, 1 ♂ 7.7 mm (MNHN-IU-2014-16754). SMIB 4 Stn DW58, 22°59’S, 167°23’E, 480-560 m, 10.III.1989, 1 ♀ 6.7 mm (MNHN-IU-2014-16755). – Stn DW61, 23°01’S, 167°22’E, 520-550 m, 10.III.1989, 1 ♂ 8.9 mm, 1 ov. ♀ 8.0 mm (MNHN-IU-2014-16756), 1 ♂ 10.7 mm (MNHN-IU-2014-16757). SMIB 8 Stn 167, 23°38’S, 168°43’E, 430-452 m, 29.I.1993, 1 ♂ 10.1 mm (MNHN-IU-2014-16758). – Stn DW201, 22°58.6’S,167°20.3’E, 500-504 m,2.II.1993,2 ov. ♀ 9.4,9.8 mm (MNHN-IU-2014-16759). BERYX 11 Stn CH 30,23°37’S,167°42’E,420-470 m, 18.X.1992, 2 ♂ 7.1, 12.2 mm (MNHN-IU-2014-16760). – Stn CP31, 23°39.12’S, 167°43.65’ E, 430-440 m, 18.X.1992, 4 ♂ 8.0-11.1 mm, 4 ov. ♀ 8.5-10.1 mm, 3 ♀ 5.3-8.8 mm (MNHN-IU-2014-16761). – Stn CP32, 23°37.70’S, 167°43.45’ E, 420-460 m, 18.X.1992, 3 ♂ 7.7-9.7 mm, 1 ov. ♀ 11.2 mm (MNHN- IU-2014-16762), 1 ♀ 9.4 mm (MNHN-IU-2014-16763). – Stn DW38, 23°37.53’ S, 167°59.42’E, 550-690 m, 19.X.1992, 1 ov. ♀ 7.2 mm, 1 ♀ 3.0 mm (MNHN-IU-2014-16764); 6 ♂ 5.3-11.8 mm, 2 ov.♀ 6.8,8.0 mm (MNHN-IU-2014-16765). – Stn CP49,23°45.22’ S,168°17.06’ E, 400-460 m, 21.X.1992, 3 ♂ 5.3-6.0 mm (MNHN-IU-2014-16766). BATHUS 3 Stn CP814, 23°47.60’E, 168°17.10’E, 444-530 m, 28.XI.1993, 1 ♂ 5.6 mm (MNHN-IU-2014-16767); 1 ♂ 5.9 mm, 1 ov. ♀ 3.3 mm (MNHN-IU-2014-16768). – Stn DW818, 23°44’S, 168°16’E, 394-401 m, 28.XI.1993, 1 ♂ 6.6 mm (MNHN-IU-2014-16769). – Stn CH 820,23°43’S, 168°16’E, 405-411 m, 28.XI.1993, 1 ov. ♀ 5.4 mm (MNHN-IU-2014-16770). LITHIST Stn CC06, 23°37.5’S,167°42.1’E, 440-579 m, 10.VIII.1999, 2 ov. ♀ 9.8, 10.6 mm (MNHN-IU-2014-16771). – Stn DW05, 23°38.2’S, 167°42.9’E, 433-500 m, 10.VIII.1999, 2 ♂ 5.9, 9.0 mm, 1 ov. ♀ 10.0 mm (MNHN-IU-2014-16772). – Stn CP02, 23°37.1’S, 167°41.1’E, 442 m, 10.VIII.1999, 1 ov. ♀ 9.6 mm (MNHN-IU-2014-16773). HALIPRO 2 Stn BT 94, 23°33’S, 167°42’E, 448-880 m, 24.XI.1996, 1 ov. ♀ 9.9 mm (MNHN-IU-2014-16774). – Stn BT 95, 24°00’S, 162°08’E, 1224-1233 m, 25.XI.1996, 1 ♀ 8.6 mm (MNHN-IU-2014-16775). NORFOLK 1, Stn DW1666,23°42’S,167°44’E, 469-860 m, 20.VI.2001, 2 ♂ 4.9,9.7 mm (MNHN-IU-2014-16776). – Stn DW1707, 23°43’S, 168°16’E, 381-493 m, 25.VI.2001, 2 ♂ 5.1, 5.7 mm (MNHN-IU-2014-16777). NORFOLK 2 Stn CP2029, 23°38.88’S, 167°44.05’ E, 438- 445 m, 22.X.2003, 17 ♂ 3.7-11.4 mm, 5 ov. ♀ 7.8-10.4 mm, 12 ♀ 3.2-7.2 mm, 2 sp. (sex indet.) 3.3, 3.7 mm (MNHN-IU-2014-16778). – Stn CP2030, 23°39.01’S, 167°44.04’E, 440-440 m, 22.X.2003, 1 ov. ♀ 10.9 mm, 1 ♀ 6.7 mm (MNHN-IU-2014-16779). – Stn DW2031, 23°38.83’S, 167°44.01’E, 440- 440 m, 22.X.2003, 1 sp. (sex indet.) 5.0 mm (MNHN-IU-2014-16780). – Stn DW2032, 23°39.14’ S, 167°43.39’E, 420-450 m, 22.X.2003, 1 ♂ 3.0 mm, 2 ♀ 5.3, 5.5 mm (MNHN-IU-2014-16781), 2 ♂ 11.3, 12.4 mm, 3 ov. ♀ 9.2-11.0 mm (MNHN-IU-2014-16782). – Stn DW2036, 23°37.81’S, 167°38.78’E, 571-610 m, 22.X.2003,8 ♂ 4.8-11.1 mm,13 ov.♀ 7.8-9.8 mm (MNHN-IU-2014-16783). – Stn DW2041,23°40.93’S,168°01.29’E,400-400 m, 23.X.2003, 1 ov. ♀ 5.3 mm (MNHN-IU-2014-16784). – Stn DW2049, 23°42.88’S, 168°15.43’E, 470-621 m, 23.X.2003, 1 ♂ 2.9 mm (MNHN-IU-2014-16785). – Stn DW2052, 23°42.29’S, 168°15.27’E, 473-525 m, 24.X.2003, 3 ♂ 4.7-5.9 mm (MNHN-IU-2014-16786). – Stn DW2056, 24°40.32’S, 168°39,17’E, 573- 600 m, 25.X.2003, 2 ♂ 5.1, 9.6 mm, 1 sp. (sex indet.) 4.5 mm (MNHN-IU-2014-16787). – Stn CP2083, 24°53.23’ S, 168°21.86’E, 530-540 m, sponge, 28.X.2003, 1 ♂ 5.5 mm, 1 ov. ♀ 5.4 mm, 1 ♀ 6.0 mm (MNHN-IU-2014-16788). – Stn DW2109, 23°47.46’S, 168°17.04’E, 422-495 m, 31.X.2003, 1 ♂ 3.2 mm (MNHN-IU-2014-16789). Solomon Islands. SALOMON 1 Stn DW1788, 9°19.4’ S, 160°15.4’E, 341-343 m, 30.IX.2001, 1 ♂ 3.8 mm (MNHN- IU-2014-16790). – Stn CP1790, 9°19.2’S, 160°10.8’E, 357 m, 30.IX.2001, 1 ♀ 5.2 mm (MNHN-IU-2014-16791). – Stn CP1831, 10°12.1’S, 161°19.2’E, 135-325 m, 5.X.2001, 1 ov. ♀ 6.4 mm (MNHN-IU-2014-16792).
SIZE„ Males, 2.9-12.4 mm; females, 3.6-11.2 mm; ovigerous females from 3.3 mm.
DISTRIBUTION„ Northeast coast of Sri Lanka, Java Sea and the Kai Islands, in 66-926 m; now Solomon Islands, Vanuatu, Loyalty Ridge, Hunter-Matthew Islands, and Norfolk Ridge, in 296-1233 m.
DESCRIPTION„ Carapace: slightly broader than long; greatest breadth 1.5-1.6 × distance between anterolateral spines. Dorsal surface feebly convex, anteriorly descended to depressed rostrum, feebly depressed between gastric and cardiac-anterior branchial regions, nearly smooth or slightly granulose in small specimens, distinctly granulose in large specimens; epigastric region smooth but a few small spines laterally, occasionally with a few tiny or obsolescent spines medially; small spine mesial to third lateral spine. Lateral margins convexly divergent (less convexly in small specimens), with 6 spines; first anterolateral, distinctly overreaching small lateral orbital spine; second small, situated on hepatic median margin and ventral to level of first and third spines, occasionally followed by 1 (rarely 2) very small spine; 4 strong spines (third to sixth) along entire length of branchial margin (last one situated near posterior end), widely spaced, occasionally intervened by small or moderate-sized spine between third and fourth, rarely small spine between fourth and fifth, and fifth and sixth, last spine rarely followed by very small spine; ridged along posterior third. Rostrum elongate triangular, with interior angle of 24-27°, length 0.4-0.6 × that of remaining carapace (greater in small specimens), breadth less than half carapace breadth at posterior carapace margin; lateral margin with at most 6 lateral spinules in distal twothirds. Pterygostomian flap granulose (in large specimens) or with tiny spines (in small specimens) on surface, anteriorly sharp angular, produced to strong spine.
Sternum: Excavated sternum with anterior margin sharply or bluntly subtriangular, surface with ridge in midline. Sternal plastron about as long as or slightly longer than broad; lateral extremities gently divergent posteriorly (in small specimens) or sternites 6 and 7 subequal in breadth and broader than sternites 4 and 5. Sternite 3 well depressed, anterolaterally sharply angular, anterior margin shallowly excavated, medially bearing U- or V-shaped or oval sinus, flanked by small incurved spine. Sternite 4 narrow relative to length, anterolateral margin nearly straight, anteriorly produced to very strong processes directed straight forward, reaching anterior end of sternite 3; posterolateral margin 0.7-0.8 × as long as anterolateral margin. Anterolateral margin of sternite 5 two-thirds length of posterior margin of sternite 4.
Abdomen: Tergites smooth and glabrous. Somite 1 with sharp transverse ridge. Somites 2 and 3 transversely ridged anteriorly; somite 2 tergite 2.3-2.6 × broader than long; pleural lateral margin concavely divergent posteriorly, sharply edged, anterolaterally and posterolaterally sharp angular. Pleura of somites 3 and 4 tapering to sharp tip. Telson 0.4-0.5 × as long as broad; posterior plate 1.1-1.4 × longer than anterior plate, posterior margin distinctly or moderately emarginate or somewhat concave.
Eye: 1.6-1.8 × longer than broad, slightly overreaching midlength of rostrum; lateral and mesial margins subparallel. Cornea slightly inflated, slightly more than half as long as remaining eyestalk.
Antennule and antenna: Ultimate article of antennular peduncle slender, 3.0-3.7 × longer than high. Antennal peduncle slender, extending far beyond cornea. Article 2 with strong distolateral spine. Antennal scale varying from barely reaching to slightly overreaching article 5, breadth 1.4-1.7 × that of antennal article 5, lateral margin rarely bearing a few small proximal spines. Distal 2 articles each with well-developed distomesial spine; article 5 2.1-2.4 × longer than article 4, breadth 0.5-0.7 × height of ultimate antennular article. Flagellum consisting of 14-22 segments (numerous in large specimens), not reaching distal end of P1 merus.
Mxp: Mxp1 with bases close to each other. Mxp3 basis with 3-5 denticles on mesial ridge, distalmost larger. Ischium with 16-25 (in small specimens), 25-30 (in large specimens) denticles on crista dentata; with 1 or 2 small spines (rarely hardly visible in small specimens) lateral to somewhat rounded distal end of flexor margin. Merus 1.8-2.2 × (greater in large specimens) longer than ischium, flattish on mesial face, flexor margin somewhat cristate with small spines on distal third; distolateral spine well developed, occasionally with a few small accompanying spines in large specimens. Carpus with distolateral spine proximally followed by a few small spines along extensor margin.
Pereopods: Scarcely setose except for distal articles.
P1: Relatively slender, 4.2-6.0 × longer than carapace, granulose on surface in large specimens, tuberculose except for palm and fingers in small specimens. Ischium dorsally bearing strong spine with small accompanying spine proximally, ventromesially with prominent subterminal spine proximally followed by successively diminishing spines. Merus with 5 rows of spines (2 dorsal, 2 mesial, 1 ventral) in small specimens; dorsal and ventral spines reduced in large specimens; length 1.1-1.3 × that of carapace. Carpus with 1 mesial and 1 dorsal row of small spines often reduced to small size or obsolete; length 1.0-1.5 × that of merus. Palm nearly smooth, 3.0-4.4 × longer than broad, with no sexual difference in proportion, subequal to or slightly longer than carpus. Fingers feebly incurved distally, not distinctly crossing, somewhat gaping in males and large females, occasionally not gaping in males; movable finger 0.4-0.5 × as long as palm, opposable margin with subtriangular proximal process fitting to longitudinal groove on opposite fixed finger when closed.
P2-4: Meri successively shorter posteriorly (P3 merus 0.8-0.9 × length of P2 merus, P4 merus 0.9 × length of P3 merus), equally broad on P2-4; length-breadth ratio 3.5-4.1 on P2, 3.1-3.7 on P3, 2.9-3.2 on P4; dorsal margin with 13-17 spines on P2, 12-16 spines on P3, 9-14 spines on P4; ventrolateral margin with a few to several spines on P2, distalmost well developed, larger than distalmost dorsal spine, other spines occasionally obsolescent on P3 and P4; another row of ventromesial spines usually on P2, occasionally absent on P3 and P4 but distal spine consistent. P2 merus 0.8-0.9 × length of carapace, 1.2 × length of P2 propodus; P3 merus 0.9-1.0 × length of P3 propodus; P4 merus 0.8-0.9 × length of P4 propodus. Carpi subequal in length or successively very slightly shorter posteriorly, relatively short; carpus-propodus length ratio,‰.36-0.44,‰.34-0.43,‰.33-0.38 on P2, P3, P4 respectively; extensor margin with row of spines distinct on P2 and P3, occasionally obsolescent on P4. Propodi successively longer posteriorly or shorter on P2 than on P3 and P4; extensor margin with or without proximal spines; flexor margin ending in pair of spines preceded by 2 or 3 (occasionally
1 or 4) in small specimens, 3-6 spines in large specimens. Dactyli longer than carpi (dactylus-carpus length ratio, 1.1-1.4 on P2, 1.2-1.4 on P3, 1.2-1.6 on P4; larger in small specimens), 0.5-0.6 × length of propodi on P2-4; flexor margin nearly straight, with row of spines strongly inclined and contiguous to one another, ultimate slender, penultimate pronouncedly broad, fully twice as broad as antepenultimate, remaining spines 9-10 in number, slender and uniform in breadth; antepenultimate subequal to ultimate in size.
Eggs. Up to 40 eggs carried; size, 0.95 × 1.01 mm - 1.07 × 1.17 mm.
Color. Male from Smib 4 Stn DW61 (MNHN-IU-2014-16757): Body and appendages pale red, abdomen translucent.
The photograph of the specimen from Vanuatu [SANTO Stn AT28] in Poore et al. (2011: pl. 7, fig. A) shows a different color pattern: body and P2-4 paler; P1 pale red with deep red bands, P2-4 with reddish bands, 2 on merus and propodus, 1 on carpus and dactylus.
REMARKS — At first glance, there seem to be two different forms: one is granulose on the carapace and P1 (Figure 158), and the other is non-granulose (Figure 159). However, the non-granulose form is small, with the maximum carapace length of 6.0 mm in males, 6.5 mm in females, whereas the granulose form measures 4.9-12.4 mm in males, 5.1-11.2 mm in females. These two forms share a row of spines along the ventromesial margin of P2 merus. In the granulose form the P1 carpus are less spinose than in the non-ovigerous form. No clear differences are found in the other characters. In addition, these forms are collected together in some stations (MNHN-IU-2014-16778; MNHN- IU-2014-16781; MNHN-IU-2014-16782). The female illustrated in Alcock & McArdle (1902: pl. 57: fig. 1a) appears to represent the non-granulose form, but the male carapace dorsum (pl. 57: fig. 1) is covered with small spines, with a distinct row of epigastric spines. Such a male is not included in the present collection. P3 and P 4 in the female (pl. 57, fig. 1a) are illustrated to bear extra spines in addition to the terminal one on the ventrolateral margin (P2 is viewed from dorsolateral side so this spination is not visible), the feature constant on P2 merus in the present material. The presence of a row of spines along the ventromesial margin of the P2 merus that is also consistent in the present material is not mentioned. Examination of the type now in the collection of the Zoological Survey of India would elaborate on its specific status.
The specimens reported under U. nanophyes from Japan by Baba (1981) are now removed from the synonymy of the species because of the following characters that are not in agreement with the present material: the carapace sizes (poc 5.1- 9.0 mm) are about the same as those of the granulose specimens but the carapace dorsal surface is smooth, not granulose, bearing scattered tiny spines on the posterior half; the epigastric region bears an uninterrupted transverse row of spines; the P2-4 meri bear only a distal spine, lacking a row of spines, on each of the ventrolateral and ventromesial margins; and the ultimate of the flexor marginal spines of P2-4 dactyli is larger than instead of subequal to the antepenultimate. This material resembles U. sexspinosus Balss, 1913a in having scattered small spines on the carapace (Balss described that the carapace dorsum is smooth and devoid of hairs and spines, but the illustration (Balss 1913b: fig. 21) shows scattered spines). According to the description by Balss (1913b), the P2-4 propodi in U. sexspinosus are entire along the flexor margin. To the best of my knowledge, a pair of terminal spines are consistent in those including U. nanophyes that have the P2-4 dactyli with a prominent penultimate spine proximally preceded by obliquely directed, closely arranged spines. It is not unlikely that the spines may have been overlooked. Unfortunately, the type could not be located (Baba et al. 2008). Uroptychus nanophyes differs from U. sexspinosus in having the carapace dorsum with spines restricted to the anterior portion mostly lateral to the epigastric region rather than scattered over the surface including posterior half. In addition, the P2-4 propodi in U. sexspinosus are entire along the flexor margin, whereas U. nanophyes has a pair of terminal spines preceded by 2 or 3 (occasionally 1 or 4) spines.
Uroptychus nanophyes also resembles U. alophus n. sp. and U. vegrandis n. sp., sharing the rostral lateral margin with a few small lateral spines, the spinose carapace lateral margin, and the P2-4 meri with a row of dorsal spines and the dactylar flexor margin with obliquely directed, closely arranged spines proximal to the pronounced penultimate spine. Characters distinguishing U. nanophyes from U. alophus and U. vegrandis are discussed under the accounts of those species.
description: Published as part of Baba, Keiji, 2018, Chirostylidae of the Western and Central Pacific: Uroptychus and a new genus (Crustacea: Decapoda: Anomura), pp. 1-612 in Mémoires du Muséum national d'Histoire naturelle 212 on pages 329-334, DOI: 10.5281/zenodo.3760976