Victoriopisa multiartus Hou

Zhao, Shuangyan, Liu, Cunqi & Hou, Zhonge, 2016, Description of a new species of Victoriopisa Karaman & Barnard, 1979 (Crustacea: Amphipoda: Eriopisidae) from China, with a key to the genus Victoriopisa, Zootaxa 4097 (2), pp. 231-243: 232-242

publication ID

http://dx.doi.org/10.11646/zootaxa.4097.2.5

publication LSID

lsid:zoobank.org:pub:F6008676-CA6B-491B-8848-2AD634DBF01A

persistent identifier

http://treatment.plazi.org/id/0396027C-473E-7D14-FF45-F8ECFE59F4E2

treatment provided by

Plazi

scientific name

Victoriopisa multiartus Hou
status

sp. nov.

Victoriopisa multiartus Hou  sp. nov.

Figs 2–7View FIGURE 2View FIGURE 3View FIGURE 4View FIGURE 5View FIGURE 6View FIGURE 7

Material examined. Holotype: IZCAS-I-A 1113, female (8.5 mm, oostegites developed and setose), Qi’ao Island, in the west side of the Pearl River Estuary, Guangdong Province, China, March, 2011, collected by Shuping Zhang. Paratype: IZCAS-I-A 1118, male (5.5 mm), same data with holotype.

Diagnosis. Body long and slender, with a smooth surface. Accessory flagellum of antenna I shorter than the article 1 of primary flagellum. Gnathopod I sexually dimorphic, carpus longer than propodus in female, but opposite in male. Propodus of gnathopod II with two excavations in female. Pereopod VII stout, with expanded basis and a shallow coxal plate. The posteroventral corner of epimeral plate III rounded. Peduncle of pleopods nearly quadrate, with paired retinacula on inner margins and plumose setae on outer margins; inner and outer rami with many articles. Uropod III much longer than uropods I and II, inner ramus scale-like, article 2 of outer ramus long and expanded, oval-shaped. Telson  with a spine on each lobe distally.

Etymology. The species name ‘ multiartus  ’ alludes to its rami of pleopods with more than 16 articles, adjective.

Description of female. (holotype, IZCAS-I-A 1113)

Body ( Fig. 2View FIGURE 2 A): length 8.5 mm, with a few setae on dorsal parts of pereonites and urosomites.

Head ( Fig. 2View FIGURE 2 A): wider than the first pereonite, eyes absent, anteroventral sinus indistinct.

Antenna I ( Fig. 2View FIGURE 2 B): about half times body length; the length ratio of peduncle articles 1–3 close to 1.0: 0.9: 0.3, with setae on posterior and anterior corners; primary flagellum with 29 articles, each with distal setae, aesthetasc present on articles 6–28; accessory flagellum ( Fig. 2View FIGURE 2 C) with two articles, about 0.5 times as long as first article of primary flagellum.

Antenna II ( Fig. 2View FIGURE 2 D): shorter, about a third length of antenna I; peduncular article 3 with five setae on posterior corner, peduncular articles 4 and 5 nearly the same length (11: 12), with two or three groups of setae on lateral margins; flagellum with two fused long articles and three short articles, reaching 0.64 times as long as peduncular article 5, with setae along the margins.

Upper lip ( Fig. 2View FIGURE 2 F): oval, bearing fine setae.

Mandible ( Fig. 3View FIGURE 3 A): left incisor with five teeth; lacinia mobilis with four teeth; accessory setal row consisting of six serrated setae, five simple setae and several fine setae; molar columnar; palp with three articles in length ratio of 1.0: 3.7: 2.8, article 3 shorter than middle article, armed with two D-setae and seven E-setae, middle article with three setae on medial margin and some tiny setae. Right mandible ( Fig. 3View FIGURE 3 B): incisor and lacinia mobilis with three teeth; accessory setal row composed of seven serrated setae; molar with a longer seta.

Lower lip ( Fig. 2View FIGURE 2 G): inner lobes well-developed, with fine setae; outer lobes with apical setae.

Maxilla I ( Fig. 3View FIGURE 3 C): inner plate with nine plumose setae and a simple seta; outer plate with nine serrated apical spines; palp with two articles, article 2 with three stout spines distinctly, seven stiff setae and a few fine setae on distal margin.

Maxilla II ( Fig. 3View FIGURE 3 D, E): inner plate with 17 plumose setae in an oblique row and simple setae on apical margin; outer plate with 14 slender simple setae and a few fine setae on apical margin.

Maxilliped ( Fig. 3View FIGURE 3 F, G): inner plate with three stout apical spines, nine plumose setae, four stiff setae on apical margin; outer plate with a number of simple setae on apical and lateral margin; palp consisting of four articles, article 2 with setae on lateral margin, article 3 with four groups of facial setae, article 4 claw-like with a seta on outer margin and a seta at the joint of nail.

Coxal gills: present on gnathopod II and pereopods III –VI ( Fig. 2View FIGURE 2 A); gills of gnathopod II ( Fig. 4View FIGURE 4 D) and pereopods III –V ( Fig. 5View FIGURE 5 A, C, E) longer than basis of corresponding pereopods, gill VI ( Fig. 5View FIGURE 5 G) much shorter than basis. All the coxal gills ovoid.

Oostegite ( Figs. 4View FIGURE 4 D; 5 A, C, E): present on gnathopod II and pereopods III –V, slender, longer than width, with numerous setae on margins.

Gnathopod I ( Fig. 4View FIGURE 4 A –C): coxal plate subrectangular; basis with four setae on posterior margin, four long setae and two short setae on posterodistal corner; carpus with five groups of setae along posterior margin; propodus palm dilated, with eight spines on posterodistal corner and two simple setae along medial side, and 11 short spines along palmar margin; dactylus robust, with a simple seta on posterior margin.

Gnathopod II ( Fig. 4View FIGURE 4 D, E): coxal plate slightly wider than length, with three setae on anterodistal corner; basis longer than ischium, merus and carpus; propodus elongate, about 2.4 times as long as the width, anterodistal corner setose; palm margin produced, with two excavations and composed of three lobes; first lobe with seven spines and three setae, second lobe with five spines, third lobe with one stout spine, three small spines and numerous setae; dactylus reaching the end of excavation, with some small spines along inner margin.

Pereopod III ( Fig. 5View FIGURE 5 A, B): slender, coxal plate much wider than length; basis elongate, with short setae on anterior margin and long setae on posterior margin; merus with three setae on posterior margin, three and six setae on anterodistal and posterodistal corners, respectively; carpus with two setae on anterior margin and six groups of long setae on posterior margin; propodus with four spines accompanied by seven setae along posterior margin and two spines on posterodistal corner; dactylus ( Fig. 5View FIGURE 5 B) long and slender, about five times as long as the width, with a penicillate seta on anteroproximal margin and a fine seta subdistally.

Pereopod IV ( Fig. 5View FIGURE 5 C, D): coxal plate wider than length; merus with setae along anterior and posterior margins; carpus with four setae along posterior margin and two setae on anterodistal corner; propodus with two setae on anterior margin, two spines accompanied by setae on posterior margin, and two spines on posterodistal corner; dactylus ( Fig. 5View FIGURE 5 D) slender, with a penicillate seta on anteroproximal margin and a fine seta subdistally.

Pereopod V ( Fig. 5View FIGURE 5 E, F): stout, basis linear oblong, with four small setae on anterior margin; merus with numerous long setae on anterior margin and two spines accompanied by six simple setae on posterior margin; anterior margin of carpus bearing six groups of setae, each group consisting of one spine and two or three simple setae, and posterodistal corner with six spines; propodus with four spines accompanied by five setae on anterior margin, three setae on posterior margin, two spines on anterodistal corner, and two spines accompanied by some setae on posterodistal corner; dactylus ( Fig. 5View FIGURE 5 F) shorter than the longest spine on propodus posterodistal corner, with two fine setae subdistally and a penicillate seta on posteroproximal margin.

Pereopod VI ( Fig. 5View FIGURE 5 G, H): longer than pereopod V, coxal plate shallow, bearing a seta on posterodistal corner and eight setae on ventral margin; basis dilated, with setae on anterior and posterior margins, respectively; merus with five groups of setae along anterior margin, two spines accompanied by setae on posterior margin, two setae on anterodistal corner, and six setae on posterodistal corner; carpus with four spines accompanied by setae on anterior margin, four setae on posterior margin, four spines accompanied by setae on anterodistal corner, and six spines accompanied by setae on posterodistal corner; propodus with three spines accompanied by four setae on anterior margin, a long seta and a short seta on posterior margin, two spines on anterodistal corner, and one spine accompanied by setae on posterodistal corner; dactylus with two fine setae subdistally and a penicillate seta on posteroproximal margin.

Pereopod VII ( Fig. 6View FIGURE 6 A): coxal plate bearing two setae on anterior margin and posterodistal corner, respectively; basis expanded, progressively wider towards posterodistal corner; merus with four groups of setae along anterior margin, four spines along posterior margin, with four setae on anterodistal corner, and a spine accompanied by two setae on posterodistal corner; carpus with three spines accompanied by setae on anterior margin, three setae on posterior margin, and three spines accompanied by one or two setae on anterodistal and posterodistal corners, respectively; propodus with two spines and two setae on anterior margin, three setae on posterior margin, two spines on anterodistal corner, and two spines accompanied by two setae on posterodistal corner; dactylus similar to that of pereopod VI, with two fine setae subdistally and a penicillate seta on posteroproximal margin.

Epimeral plates ( Fig. 2View FIGURE 2 A): plate I bare; plate II with six setae on ventral margin; plate III posteroventral corner rounded, with three setae.

Pleopods I –III ( Fig. 6View FIGURE 6 C –E): peduncles nearly quadrate, with paired retinacula on inner margins, outer margins with nine plumose setae in pleopod I, six plumose setae in pleopod II, and three plumose setae in pleopod III; inner and outer rami with 16 and 24 articles in pleopod I, 19 and 22 articles in pleopod II, and 18 and 22 articles in pleopod III; both rami fringed with plumose setae.

Uropod I ( Fig. 6View FIGURE 6 F): peduncle distinctly longer than rami, with eight spines on outer margin, one and two spines on outer and inner distal corners, respectively; outer ramus as long as inner ramus, with three spines on outer margin and three spines on inner margin; inner ramus with two and one spines on outer and inner margins; both rami with five terminal spines.

Uropod II ( Fig. 6View FIGURE 6 G) about 0.6 times as long as uropod I; peduncle with two spines on outer margin, one spine and three setae on outer distal corner, and one spine on inner distal corner; outer ramus 0.7 times as long as peduncle, with two spines on outer margin and one spine on inner margin; inner ramus 1.4 times as long as outer ramus, with two spines on outer margin and one spine on inner margin; both rami with five terminal spines.

Uropod III ( Fig. 6View FIGURE 6 H) much enlarged, peduncle shorter than outer ramus, about 0.8 times as long as proximal article of outer ramus, with three small spines on outer margin, five spines on inner margin, one spine accompanied by four setae on outer distal corner, and one spine on inner distal corner; proximal article of outer ramus with six groups of setae on outer margin, five spines on inner margin, four setae on outer distal corner, and five spines on inner distal corner, terminal article of outer ramus oval, slightly longer than proximal article, with three groups of small setae on outer margin, seven spines on inner margin, and numerous slender setae on apical margin; inner ramus scale-like, about 0.10 times as long as outer ramus, with three spines distally.

Telson  ( Fig. 3View FIGURE 3 H) longer than width, cleft for two-thirds of the length; each lobe with two spines on lateral margin, one spine accompanied by two or three simple setae on distal margin and a pair of long penicillate setae on dorsal surface.

Description of male. (paratype, IZCAS-I-A 1118)

The only male specimen in poor condition, dactylus of gnathopod I missing. Generally similar to female except for gnathopods and pereopod VII.

Gnathopod I ( Fig. 7View FIGURE 7 A): similar to that of female; coxal plate oval, with two setae on anterior margin and one seta on posterior margin; basis with three setae on posterior margin, two long setae and two short setae on posterodistal corner; merus longer than carpus, with many small setae on posterior margin; carpus 0.48 times as long as merus, with simple setae on posterior margin; propodus with many simple setae on surface and palmar margin, about 2.5 times as long as carpus.

Gnathopod II ( Fig. 7View FIGURE 7 B): much larger than gnathopod I; coxal gill elongate, much longer than the width, about 1.45 times as long as basis; basis with three setae on posterior margin and five setae on posterodistal corner; propodus elongate with setose on surface; palm with an excavation in the half place and composed of two lobes, first lobe with six spines and fine setae, second lobe with one stout spine, three small spines and numerous setae; dactylus robust, with a seta on outer margin and some small spines along inner margin.

Pereopod VII ( Fig. 7View FIGURE 7 C): similar to that of female; basis extremely expanded, with setae on anterior and posterior margins; merus moderately dilated, with some setae along anterior margin and three spines on posterior margin; carpus as long as propodus, with two pairs of spines on anterior margin, two spines accompanied by a simple seta on anterodistal corner, and two spines accompanied by three simple setae on posterodistal corner; propodus with a pair of spines on anterior margin, two spines on anterodistal corner, one seta on posterior margin, and two spines accompanied by two small setae on posterodistal corner, one of the two spines on posterodistal corner of the propodus as long as dactylus; dactylus slender, with two fine setae subdistally.

Remarks. The new species is assigned to Victoriopisa  after fused flagellum in antenna II, the expanded basis of pereopod VII, and extremely elongated Uropod III. Lim et al. (2010) presented a detailed comparison for eight species of the genus Victoriopisa  . Subsequently Ariyama (2015) described the ninth species of Victoriopisa  ( V. wadai  ) from Japan. Victoriopisa multiartus  sp. nov. is the tenth.

The current species is characterized by gnathopod I sexual dimorphism, female with longer carpus than propodus, while male with longer propodus than carpus; gnathopod II with excavated palm; and terminal article of outer ramus in uropod III dilated, oval-shaped.

Victoriopisa multiartus  sp. nov. is most similar to V. wadai  from Japan in sharing (1) gnathopod II with excavated palm; (2) peduncles of pleopods with plumose setae; and (3) expanded basis and merus in pereopod VII. However, the new species is distinguished from the latter in the following respects (features of V. wadai  in parentheses): (1) incisor of mandible with five teeth in left (six in V. wadai  ) and three teeth in right (five in V. wadai  ); (2) lacinia mobilis of left mandible with four teeth (five in V. w a da i); (3) article 2 of maxilla I palp with three stout spines (four in V. wadai  ); (4) gnathopod I of the male with oval coxal plate (trapezoidal in V. wadai  ); (5) gnathopod II basis with three setae on posterior margin (four in V. w a da i) and palm with an excavation in male (two in V. wadai  ); (6) rami of pleopods with up to 24 articles (18 in V. wadai  ); and (7) the terminal article of outer ramus in uropod III dilated, oval-shaped (slender in V. wadai  ).

The new species differs from V. ryukyuensis  in the body with a few setae on dorsal parts (smooth in V. ryukyuensis  ); incisor of left mandible with five teeth (six in V. ryukyuensis  ) and three teeth in right mandible (five in V. ryukyuensis  ); lacinia mobilis of right mandible with three teeth (four in V. ryukyuensis  ); gnathopod I (female) palm with eight spines (ten in V. ryukyuensis  ); gnathopod II (female) palm with 16 spines (seven in V. ryukyuensis  ); and rami of pleopods with up to 24 articles (20 in V. ryukyuensis  ).

The new species differs from V. papiae  in the article 2 of maxilla I palp with three short robust spines and some setae on apical margin (only setae in V. papiae  ); gnathopod II of the male with seven spines on palmar margin (one in V. papiae  ); and the ventral margin of epimeral plate II with six setae (ten longer plumose setae in V. papiae  ).

The new species differs from V. tinggiensis  in flagellum of the antenna II with five articles (three or four articles in V. tinggiensis  ); article 3 of mandible palp with two D-setae and seven E-setae (three D-setae and six Esetae in V. tinggiensis  ); palm of gnathopod II with an excavation (palm slightly convex in V. tinggiensis  ); and the ventral margin of epimeral plate II with simple setae (long plumose setae in V. tinggiensis  ).

Victoriopisa marina  and V. australiensis  have been reported from Australia, which are very similar to each other. The new species differs from them in the gnathopod I of male with oval coxal plate (anteroventral corner produced in V. m a r i n a and V. australiensis  ). Victoriopisa multiartus  sp. nov. can be distinguished from V. epistomata  , reported from south coast of South Africa to South West Africa ( Griffiths, 1974), in the excavated palm of gnathopod II and oval-shaped article 2 of outer ramus in uropod III. Distinguishing features among species of the genus Victoriopisa  are summarized in Table 1 and a key to the genus Victoriopisa  is presented as follows.

species Character state Character list:

I eyes [0: absent; 1: weak]

II lateral cephalic lobe

III antenna I peduncle, (article 1: article 2) length ratio IV antenna I, primary flagellum, no. of articles V mandible palp, (article 2: article 3) length ratio VI maxilla I, inner plate armature (no. of setae) VII maxilla I, outer plate armature (no. of stout spines) VIII maxilla II, inner plate, no. of setae on oblique row IX maxilliped, inner plate armature (no. of stout spines) X gnathopod I, sexual dimorphism (?: lack of paired specimens) XI uropod I, peduncle, no. of basofacial robust spines XII uropod III, outer ramus (proximal article: terminal article) length ratio XIII uropod III, (peduncle: proximal article of outer article) length ratio XIV telson  , no. of lateral spines

XV telson  , no. of distal spines

TABLE 1. Main distinctive features of the species of Victoriopisa.

          VI   VIII IX X XI XII   XIV XV
    rounded>1                      
    not>1 produced                      
V. ryukyuensis Morino, 1991