Eudorella haradai , Akiyama, Tadashi & Gamô, Sigeo, 2012

Akiyama, Tadashi & Gamô, Sigeo, 2012, The cumacean Genus Eudorella (Crustacea: Peracarida) from Japanese Waters, Northwest Pacific, and E. suluensis sp. nov. from the Sulu Sea, Indo-West Pacific, Zootaxa 3319, pp. 1-56: 34-38

publication ID

http://doi.org/ 10.5281/zenodo.213431

persistent identifier

http://treatment.plazi.org/id/084687A9-CA77-2956-FF3D-FEC3FBC6FED3

treatment provided by

Plazi

scientific name

Eudorella haradai
status

sp. nov.

Eudorella haradai  sp. nov.

( Figs. 23–25View FIGURE 23View FIGURE 24View FIGURE 25)

Material examined. Holotype, ovigerous female carrying 7 spherical embryos, 4.3 mm, dissected (NSMT-Cr 22134), off Chiba, 34 º 43.38 ˏN, 140 ° 46.67 ˏE – 34 ° 41.22 ˏN, 140 ° 44.60 ˏE, 2221–2240 m (KT-01- 8, Station TK- 4), 23 June 2001. Paratypes; subadult male, 5.0 mm, dissected, 1 preparatory female, 4.8 mm, dissected (NSMT-Cr 22135), Kumano Basin, 33 º 42.53 ˏN, 136 ° 43.32 ˏE – 33 ° 43.28 ˏN, 136 ° 44.72 ˏE, 1982–2012 m, 1 May, 2004 (KT- 04- 6, St. KN- 8 - 1); 1 subadult male, 5.4 mm, dissected (NSMT-Cr 22136), off Kushiro, 42 ° 23.83 ˏN 145 ° 31.06 ˏE – 42 °22.00ˏN, 145 ° 27.70 ˏE, 3108–3265 m (KH-01- 2, St. XR- 5), 16 September 2001; 1 preparatory females, damaged during collection, dissected (NSMT-Cr 22137), off Shimokita Peninsula, 41 °04.5ˏN, 143 °52.0ˏE – 41 °04.5ˏN, 143 ° 520 ˏE, 3000 m (KT-08- 27, St. B 16), 25 October 2008.

Description. Females ( Figs. 23View FIGURE 23, 24View FIGURE 24). Body slender; integument moderately calcified, with few setae. Carapace length 0.21 times total body length, 1.3–1.4 times greatest width and 1.2–1.3 times the depth; upper front corner with sparse short setae projecting upward and forward ( Fig. 23View FIGURE 23 C); frontal margin not serrated; antennal notch with 2 teeth each on upper and lower ends; anterolateral angle with tooth projecting forward, succeeded by 12 small teeth on inferior margin. Pereon length 1.1–1.2 times that of carapace. Pleon 0.56 or 0.57 times total body length; dorso-posterior margin of 5 th segment with a pair of long setae exceeding uropods in length.

Antenna 1 ( Fig. 23View FIGURE 23 D) 3 rd article of peduncle and main flagellum subequal in length to 2 nd, with 2–4 plumose and 1–2 simple setae on outer margin, and with 5 plumose setae on inner margin; 1 st article of peduncle with 2–3 setae on inner margin and with no setae on lower margin; main flagellum longer than 2 nd article of peduncle, with 2–3 simple setae on outer margin. Accessory flagellum shorter than 1 st article of main flagellum. Antenna 2 ( Fig. 23View FIGURE 23 E) with no setae on lower margin. Mandibles ( Fig. 23View FIGURE 23 F): left mandible with tridentate lacinia mobilis; right mandible with sharply pointed spiniform seta distally. Maxilla 1 and maxilla 2 normal ( Fig. 23View FIGURE 23 G, H). Maxilliped 1 with 3–4 small branchial lobules ( Fig. 23View FIGURE 23 I). Maxilliped 2 ( Fig. 23View FIGURE 23 J, K) basis shorter than combined length of ischium, merus and carpus, with several setae on inner margin. Maxilliped 3 ( Fig. 23View FIGURE 23 L) basis subequal to length of distal articles together, with 4–9 and 5–7 setae on inner margin and ventral surface, respectively; carpus with 8–9 plumose setae on inner margin.

Pereopod 1 ( Fig. 24View FIGURE 24 A) basis 0.7 times distal articles together, with 4 and 3–4 plumose setae on inner and outer margin respectively; propodus 1.0– 1.1 times carpus and 1.4 or 1.8 times dactylus. Pereopod 2 ( Fig. 24View FIGURE 24 B) basis length 0.8–0.9 times length of remaining distal articles; carpus 1.3–1.5 times merus and 0.8–0.9 times combined length of propodus and dactylus; propodus with a notch on distal corner, reaching middle portion of article; dactylus not swollen distally, with 10 or 11 stiff setae projecting radially. Pereopods 3, 4 and 5 ( Fig. 24View FIGURE 24 C –E) basis lengths 1.6 –2.0, 1.3–1.6 and 1.2–1.3 times distal articles together respectively.

Uropod ( Fig. 24View FIGURE 24 F). Peduncle length 1.4–1.5 times length of pleonite 6, 0.84–0.93 times exopod, 0.86–0.97 times 1 st article of endopod; with 3–4 spiniform setae on its inner margin; exopod 1.0– 1.1 times 1 st article of peduncle, with 6–9 setae on inner margin and distal end, 4–5 setae on dorsal surface and 3–4 setae on ventral surface. Endopod 1 st article 3.6–3.7 times 2 nd article, with 8–10 spiniform setae on inner margin and 3 setae on outer margin; 2 nd article with 4 spiniform setae on inner margin and a long, robust terminal seta.

2 subadult males ( Fig. 25View FIGURE 25). Carapace length 0.20, 0.22 times total body length, 1.44 times the greatest width and 1.29 times depth; upper front corner with a bundle of short setae ( Fig. 25View FIGURE 25 C); lower portion of frontal margin with several teeth directed upward and downward; antennal notch absent; inferior margin with 14–17 teeth, foremost one prominent, directed forward. Pereon length 1.0, 1.2 times carapace length. Pleon 0.56, 0.57 times total body length; 2 long setae on dorso-posterior end of 5 th pleonite lost during collection, only sockets present.

Antenna 1 ( Fig. 25View FIGURE 25 D) 1 st article of peduncle with 0 and 1–4 setae on lower and inner margin respectively; 3 rd article of peduncle shorter than 2 nd, with 2–4 and 5 plumose setae on outer and inner margin, respectively. Main flagellum length subequal to 2 nd article of peduncle; 1 st article with 2 or 3 simple setae on outer margin; accessory flagellum shorter than 1 st article of peduncle. Antenna 2 ( Fig. 25View FIGURE 25 E) with 3 plumose setae on proximal region of peduncle. Maxilliped 3 ( Fig. 25View FIGURE 25 F) basis 1.2 times distal articles together, with 4 or 9 plumose setae on inner margin and 5 or 7 plumose setae on ventral surface.

Pereopod 1 ( Fig. 25View FIGURE 25 G) basis length 0.7, 0.8 times distal articles together; propodus 1.3, 1.4 times carpus and 1.6, 2.0 times dactylus. Pereopod 2 ( Fig. 25View FIGURE 25 H) basis 1.0 or 1.1 times distal articles together; carpus 1.3 times merus and 0.8 times combined length of propodus and dactylus; dactylus with 10 or 11 stiff setae. Pereopods 3–5 ( Fig. 25View FIGURE 25 I –K) basis length 2.1 or 2.7, 1.7 or 2.1, and 1.4 or 1.5 times distal articles combined, respectively. Pleopod 1 normal ( Fig. 25View FIGURE 25 L).

Uropod ( Fig. 25View FIGURE 25 M) peduncle 1.3–1.4 times pleonite 6, 0.87, 0.95 times exopod, and 0.87, 0.91 times 1 st article of endopod, with 3 spiniform setae on inner margin. Exopod length 0.96, 1.00 times length of 1 st article of endopod, with 7, 9 setae on inner margin and apical end, with 4 setae on dorsal surface, and with 2, 5 setae on ventral surface. Endopod 1 st article length 3.3, 3.5 times 2 nd article, with 8, 12 spiniform setae on inner margin and with 4 setae on outer margin; 2 nd article with 4 spiniform setae on inner margin.

Etymology. The specific name is dedicated to Dr. Isokichi Harada in honor of his contribution to cumacean taxonomy.

Remarks. The present new species resembles E. pacifica Hart, 1930  , from the North Pacific. Based on the description by Hart (1930) and the key to species in the genus by Watling (1991), females of the E. haradai  , sp. nov. can be distinguished from E. pacifica  by the following characters. (1) The main flagellum of antenna 1 is longer than the 2 nd article of the peduncle (subequal in E. pacifica  ). (2) The basal article of this flagellum is distinctly longer than the accessory flagellum (subequal or slightly longer in E. pacifica  ), (3) this basal article has 3 simple setae (no seta in E. pacifica  ). (4) The uropod peduncle is shorter than the basal article of the endopod (longer in E. pacifica  ). Eudorella haradai  also resembles E. truncatula ( Bate, 1856)  , but the females are distinguished the following. (1) The side plates of pereonites 2 and 3 are not well developed (well developed in E. truncatula  ). (2) There are 2 long setae on the dorso-posterior end of pleonite 5 (no long setae in E. truncatula  ). (3) The 2 nd and 3 rd articles of the peduncle of antenna 1 are subequal in length (2 nd article longer than 3 rd in E. truncatula  ). (4) The branchial lobules of maxilliped 1 are small (large, well developed in E. truncatula  ). (5) The propodus of pereopod 1 is subequal in length to the carpus (longer than the carpus in E. truncatula  ). (6) The uropod peduncle is shorter than the exopod and endopod 1 st article (longer than endopod 1 st article in E. truncatula  ).

Eudorella haradai  , sp. nov., also resembles to E. divae Mühlenhardt-Siegel, 2005  , in the shape of the uropod, but is distinguishable from the latter by: (1) an antennal notch with two teeth on the lower end (five teeth in E. divae  ); (2) The antenna 1 peduncle 2 nd article is subequal in length to the 3 rd (longer than 3 rd in E. divae  ); (3) The carpus of maxilliped 2 has 10 or more setae on the inner margin (5 setae in E. divae  ); and (4) the ischium of pereopod 2 is absent, and the dactylus does not taper (the ischium is present, and the dactylus tapers in E. divae  ).

Distribution. Pacific coast of northern and southern Honshu, 1982–3265 m.

Kingdom

Animalia

Phylum

Arthropoda

Class

Malacostraca

Order

Cumacea

Family

Leuconidae

Genus

Eudorella

Loc

Eudorella haradai

Akiyama, Tadashi & Gamô, Sigeo 2012
2012
Loc

E. divae Mühlenhardt-Siegel, 2005

Muhlenhardt-Siegel 2005
2005