Ampelisca pseudobicarinata, Souza-Filho & Souza & Valério-Berardo, 2009

Souza-Filho, J. F., Souza, A. M. T. & Valério-Berardo, M. T., 2009, Description of four new species of the genus Ampelisca (Amphipoda, Ampeliscidae) from the northeastern and southeastern coasts of Brazil and designation of a neotype for Ampelisca soleata Oliveira, 1954, Journal of Natural History 43 (37 - 38), pp. 2391-2423 : 2404-2409

Ampelisca pseudobicarinata sp. nov.

( Figure 8–10 )

Material examined

Holotype, female, 12 mm, Baía de Todos os Santos, Salvador, Bahia (13°00.299′ S, 38°46.699′ W), O. Falcão col., 26 April 1997, MNRJ 21517 . Paratypes, Baía de Todos os Santos, Salvador, Bahia (13°00.299′ S, 38°46.699′ W), 6.9 m, O. Falcão col., 26 April 1997, MNRJ 15808 , 2 females . REVIZEE Score NE, #113, 2°13.8′ S, 39°53.4′ W, 40 m, N. Oc. Antares col., 20 November 2000, MNRJ 21586 , 1 female (dissected and draw) . Off Rio Grande do Norte State , 3°01′ 59.9″ S, 39°02′.6″ W, 31 m, 1 December 2003, MNRJ 21518 , 3 females . Off Rio Grande do Norte State , 3°07′ 53.2″ S, 38°49′ 26.2″ W, 36 m, 02 December 2003, MNRJ 21519 , 5 females .

Etymology

This species name is formed from the Greek prefix pseudo, meaning false, feigned, erroneous, and bicarinata , because this species is very similar to A. bicarinata Goeke and Heard, 1983.

Diagnosis

Head concave and anteroventral margin subparallel to anterodorsal margin. Antenna 1 shorter than antenna 2 peduncle. Antenna 2 about one-third of body length, Pereopod 5 dactylus with five apical cusps. Pereopod 6 dactylus with 12 apical cusps. Pereopod 7 basis posterior margin oblique, reaching to end of merus, dactylus subequal to propodus, with one robust seta on posterior distal margin. Pleonite 3 dorsal margin drawn out into two parallel side lamellae. Epimeron 3 posteroventral corner drawn out into a short spine. Uropod 2 outer ramus with a long apical robust seta. Uropod 3 rami foliaceous and lanceolate, with facial spines and robust setae on outer margins of rami. Telson notched pointed at apex, each notch bearing two robust and two simple seta.

Description

Holotype, female 12 mm. Head ( Figure 8 ) longer than deeper, as long as first three body segments combined, concave and anteroventral margin subparallel to anterodorsal margin. Two pairs of corneal lenses present, strongly developed. Antenna 1 ( Figure 8 ) shorter than antenna 2 peduncle, peduncular article 2 1.5 times longer than article 1 and 2.1 times longer than article 3; flagellum with nine articles, longer than peduncle. Antenna 2 ( Figure 8 ) about one-third of body length, fourth peduncular article 1.5 times longer than fifth peduncular article; flagellum with 19 articles, longer than peduncle.

Mandible ( Figure 8 ) accessory setal row with nine setae; palp article 2 not inflated, both margins with long simple setae, article 3 0.6 times article 2, with setae on inner and apical margins. Maxilla 1 ( Figure 8 ) inner plate with one apical seta; outer plate with 11 serrate robust setae; palp article 2 with 3 distal cusps accompanied by five robust setae and five facial setae and three long simple setae on outer margin. Maxilliped ( Figure 8 ) inner plate rectangular distally with two acuminate robust setae and nine plumose setae on distal margin; outer plate reaching to one-third of the palp article 3, bearing six chisel-shaped robust setae along inner margin and three apical robust setae; palp article 3 with article 4 inserted at distal mid-length, article 4 with nail and with four short simple setae on the inner and distal margin. Upper lip, lower lip and maxilla 2 ( Figure 8 ) with basic characters for the genus.

Coxae 1–4 ( Figure 9 ) longer than broad. Coxae 1 and 2 with a row of plumose setae on ventral margins. Coxa 1 distally widened and with a short notch on posteroventral corner. Gnathopod 1 ( Figure 9 ) basis weakly inflated distally, with long plumose setae on posterior margin and long and short simple setae on anterior margin; ischium with one seta on posterodistal corner; merus with long setae along posterior margin; carpus 1.4 times propodus length, both articles with posterior margins with pinnate setae; propodus with simple setae on anterior margin; dactylus curved, with five robust setae along inferior margin. Gnathopod 2 ( Figure 9 ) basis weakly inflated distally, with four long simple setae on posterior margin and with one long plumose seta and 11 short simple setae on anterior margin; ischium and merus with long setae on distoposterior margins; carpus twice propodus length, both articles with posterior margins with pinnate setae and anterior margin with simple setae; dactylus slightly curved, with four setules pinnate along inferior margin. Pereopod 3 and 4 ( Figure 9 ) similar in shape but the fourth is more massive and setose than third, both with dactyli longer than combined lengths of carpus and propodus (1.2 times). Pereopod 3 ( Figure 9 ) merus with eight short simple setae along posterior margin and two long plumose setae on posterodistal corner and three short simple setae on anterodistal margin, anterodistal corner not drawn out; carpus with long plumose setae on posterior margin and two simple setae on anterodistal corner; propodus with long simple setae on anterior margin. Pereopod 4 ( Figure 9 ) basis with short simple setae on anterodistal margin and long simple and simple setae along posterior margin; merus length 3.2 times breadth, heavily plumose setae on both margins; carpus with plumose setae on posterior margin; propodus with long simple setae on both posterior margin and posterodistal corner, anterior margin with five short simple setae. Pereopod 5 ( Figure 9 ) basis subovoid, anterior margin with 19 plumose setae; carpus 1.1 times longer than propodus and drawn out posterodistally, anterior margin with long simple setae, posterior margin with three combs of robust setae (2–3–3), bearing three long and four short setae on posterodistal corner; propodus anterior margin with two short setae and two plumose setae, anterodistal angle with three long setae, posterior margin with five simple setae; dactylus short, with five apical cusps. Pereopod 6 ( Figure 9 ) basis subovoid, anterior margin with six long plumose and four short simple setae and one long seta in anterodistal corner; carpus slightly longer than propodus (1.1 times), posterior margin with comb of robust setae (2–3–4), posterodistal corner produced, bearing four long setae and three robust setae; anterior margins of carpus and propodus with a row of robust setae; anterodistal corner of the propodus with one long seta, posterior margin with a row of short setae; dactylus short, with 12 apical cusps. Pereopod 7 ( Figure 10 ), basis posterior margin oblique, reaching to end of merus, with plumose setae on ventroposterior margin; ischium shorter than merus; merus posterodistal lobe reaching to one-third of carpus length, lobe margin with one short simple seta; carpus anterior margin with four robust setae, anterodistal corner with one robust seta; posterodistal corner with one long plumose seta and three robust setae; propodus longer than carpus (twice), length 1.7 times breadth, anterodistal corner with six robust setae; dactylus subequal in length to propodus, curved anterodistally with one robust seta on posterior distal margin.

Pleonite 3 ( Figure 10 ) dorsal margin drawn out into two parallel side lamellae. Epimeron 3 ( Figure 10 ) slightly sinuous, posteroventral corner drawn out into a short spine. Urosomite 1 ( Figure 10 ) with dorsal margin drawn out into ovate lamella with two short setae on posterior margin. Uropod 1 ( Figures 8 and 10 ) extending to end of uropod 2 rami, peduncle subequal in length to rami, inner margin with eight robust setae, outer margin with proximal triangular process and three robust setae, outer facial margin with five robust setae; inner ramus subequal in length to outer ramus, with six robust setae on inner margin; outer ramus with three short robust setae on outer facial margin. Uropod 2 ( Figure 10 ) peduncle longer than rami, inner margin with one robust seta and with a comb of three robust setae on apical corner, outer margin with four robust setae; rami subequal in length; inner ramus with a row of nine robust setae; outer ramus with a long apical robust seta more than half the length of ramus and three robust setae on inner margin and eight robust setae on outer margin. Uropod 3 ( Figure 10 ) peduncle shorter than rami, with three robust setae on inner margin; rami foliaceous and lanceolate, inner margins of both rami with long plumose setae, outer ramus with one midway short plumose seta and robust setae on outer margin, outer facial margin with a row of short spines; facial inner subapical margin of inner ramus serrate and with plumose setae; inner margin with two rows of short robust setae, outer margin with one midway short plumose seta. Telson ( Figure 10 ) cleft (0.6 times), each lobe with two dorsal robust setae and notched pointed at apex, each notch bearing two simple setae.

Remarks

Ampelisca pseudobicarinata sp. nov. appears to be closely related to A. bicarinata Goeke and Heard, 1983, from the Gulf of Mexico, in having head concave and anteroventral margin subparallel to anterodorsal margin; epimeron 3 slightly sinuous, posteroventral corner drawn out into a short spine; pleosomite 3 bicarinate; urosomite 1 with dorsal margin drawn out into lamella and uropod 3 rami foliaceous and lanceolate. However, the new species can be distinguished from A. bicarinata , by the number of accessory cusps of dactylus of pereopods 5 and 6 (5 × 4 and 5 × 12, respectively); pereopod 7 basis reaching to the end of merus (longer in A. bicarinata ); higher number of robust setae on peduncles and rami of uropod 1 and 2; uropod 3 with facial spines and robust setae on rami; and telson notched and pointed at apex.

Geographic distribution

Brazil: off of Ceará and Rio Grande do Norte States and Baía de Todos os Santos, Bahia State .

Figures

Figure 8. Habitus: Ampelisca pseudobicarinata sp. nov., holotype, female, 12 mm, Baía de Todos os Santos, Salvador, Bahia (13°00.299′ S, 38°46.699′ W), 26 April 1997, MNRJ 21517. Mouthparts: Paratype, female, 7.0 mm, REVIZEE Score NE, #113 (2°13.8′ S, 39°53.4′ W), N. Oc. Antares, 20 November 2000, MNRJ 21586. Scale bar 0.1 mm.

Figure 9. Ampelisca pseudobicarinata sp. nov., paratype, female, 7.0 mm, REVIZEE Score NE, #113 (2°13.8′ S, 39°53.4′ W), N. Oc. Antares, 20 November 2000, MNRJ 21586. Scale bar 0.2 mm.

Figure 10. Ampelisca pseudobicarinata sp. nov., paratype, female, 7.0 mm, REVIZEE Score NE, #113 (2°13.8′ S, 39°53.4′ W), N. Oc. Antares, 20 November 2000, MNRJ 21586. Scale bar 0.2 mm.