Ampelisca anae, Valério-Berardo, Maria Teresa, 2008

Valério-Berardo, Maria Teresa, 2008, Six new species of deep water Ampeliscidae (Crustacea: Amphipoda) from Brazilian Coast, Zootaxa 1844, pp. 1-24 : 10-13

Ampelisca anae sp. nov.

( Fig. 5–6 )

Material Examined: Holotype: 1 female, 5 mm, 22°27’31,62”S – 40°09’23,19”W, 750 m., R/V Astro Garoupa, 21/XI/2002; MNRJ 20525; Paratypes: 1 male, 6 mm, 21°52’59,6”S – 39°55’30,635”W, 750 m., R/V Astro Garoupa, 12/XII/2002; MNRJ 20531; 2 females, 22°04’32,8”S – 39°54’11,4”W, 750 m., R/V Astro Garoupa, 30/VI/2003; MNRJ 20527; 22°27’31,1”S – 40°09’23,5”W, 750 m., R/V Astro Garoupa, 18/VI/2003; MNRJ 20533; 21°52’59,2”S – 39°55’32,2”W, 750 m., R/V Astro Garoupa, 29/VI/2003; MNRJ 20532; 1 female 22°31’12,47”W – 40°15’11,08”W, 750 m., R/V Astro Garoupa, 22/XI/2002; MNRJ 20522; 1 female 21°57’17,490”S – 39°56’01,08”W, 750 m., R/V Astro Garoupa, 12/XII/2002; MNRJ 20537; 1 female, 21°57’11,8”S – 39°56’04,2”W, 750 m., R/V Astro Garoupa, 29/VI/2003; MNRJ 20531.

Etymology: The species is dedicated to the author’s daughter.

Diagnosis: Head with small projection on anterodorsal corner of head. Antenna 1 subequal in length to antenna 2 peduncle. Antenna 2 shorter than body length. Coxa 1 and 2 with notch on posteroventral corners. Pereopods 5 and 6 dactyli without apical cusp. Pereopod 7 basis posterior margin obliquely rounded, propodus subequal in length to carpus, not stout, length 1.3 X breadth, dactylus shorter than propodus, bearing 1 subdistal seta. Epimeron 3 posteroventral corner with 1 spine. Uropod 3 rami lanceolate, inner ramus with 2 robust setae along outer margin. Telson lobes pointed at apex, with 1 pair of robust distal setae.

Description: Holotype, female, 5 mm. Head ( Fig. 5 ) longer than first three body segments combined, with small projection on anterodorsal corner of head, anteroventral margin oblique to half of the medium anterior margin of the head. Two pairs of corneal lenses present. Antenna 1 ( Fig. 5 ) subequal in length to antenna 2 peduncle, peduncular article 2 1.8 X article 1, without setae on ventral margin; flagellum with 4 articles, shorter than peduncle. Antenna 2 ( Fig. 5 ) shorter than body length, peduncular article 4 subequal in length to article 5; flagellum with 9 articles. Mandible ( Fig. 5 ) with 8 accessory setal row; mandibular palp article 2 elongate, not inflated, with long plumose and simple setae on inner margin, article 3 0.4 X article 2, with apical plumose and simple setae. Maxilla 1 ( Fig. 5 ) inner plate with two apical simple setae, lobe plate with 9 setal-teeth; palp article 2 provided with 2 distal cusps accompanied by 4 robust setae, 1 plumose seta and 2 simple setae. Maxilliped ( Fig. 5 ) inner plate rectangular distally with 1 apical robust seta and 4 apical simple setae, outer plate reaching to end of the palp article 2, bearing 4 chisel-shaped robust setae along medial margin, and 2 apical robust setae; palp normal for the genus, article 3 clavate. Upper lip, lower lip and maxilla 2 with basic characters for the genus.

Coxae 1–4 ( Fig. 5 ) longer than broader. Coxa 1 and 2 with notch on posteroventral corners, with a row of plumose setae on ventral margins. Gnathopod 1 ( Fig. 5 ) basis inflated middledistally with one row of simple setae on posterior margin, anterior margin with a medial simple seta; isquium and merus with plumose and pinnate setae on posterior margin; carpus longer than propodus (1.2 X), both articles with pinnate setae on posterior margins; dactylus slightly curved, longer than half of palm length, inferior margin smooth. Gnathopod 2 ( Fig. 5 ) slender than gnathopod 1, basis with long setae on both margins; merus with plumose setae on posterior margin; carpus longer than propodus (1.4 X), with long pectinate setae on posterior margin; propodus with simple setae along posterior margin, anterior margin with distal simple setae; dactylus longer than half of palm length, inferior margin nacked. Pereopod 3 and 4 ( Fig. 5 ) similar in shape but the fourth is more massive and setose than third, both with dactyli subequal in length to carpus and propodus combined. Pereopod 3 merus with plumose setae on distal corner of both margins, anterodistal corner not produced; carpus with plumose setae on posterior margin. Pereopod 4 basis posterior margin with a row of plumose setae; merus length 3.2 X breadth, both margins with plumose setae; carpus with plumose setae on both margins. Pereopod 5 ( Fig. 6 ) basis subovoid, anterior margin with 3 plumose and 8 robust setae; carpus longer than propodus (1.2 X), sligthly produced posterodistally, bearing 2 setae, posterodistal margin with 3 setae; dactylus very short, without apical cusp. Pereopod 6 ( Fig. 6 ) basis subrectangular, anterior margin with 6 short simple setae; carpus longer than propodus (1.3 X), posterodistal corner slightly produced, bearing 2 long setae, anterior margin with 4 setae; propodus anterodistal margin with setae; dactylus very short, without apical cusp. Pereopod 7 ( Fig. 6 ) basis posterior margin rounded and reaching to end of distal margin of carpus, with plumose setae; merus longer than isquium (1.1 X), with 2 long plumose setae on posterodistal corner; carpus anterodistal corner with 2 robust setae posterodistal margin with 2 long simple setae; propodus subequal in length to carpus, not stout, length1.3X breadth, anterodistal corner with 2 robust setae, posterodistal corner with 3 long setae; dactylus shorter than propodus (0.8 X), bearing 1 subdistal seta.

Epimeron 3 ( Fig. 6 ) posteroventral corner with a spine. Urosomite 1 ( Fig. 6 ) not produced dorsally into a carina. Uropod 1 ( Fig. 6 ) extending to end of uropod 2 peduncle, peduncle subequal in length to the rami, inner margin with 2 robust setae; rami equal in length, nacked. Uropod 2 ( Fig. 6 ) peduncle length subequal to inner ramus and with 2 apical robust setae on inner corner; inner margins of both rami with 1–2 robust setae; outer ramus shorter than inner ramus with a long apical robust seta. Uropod 3 ( Fig. 6 ) rami lanceolate longer than peduncle, outer ramus longer than inner ramus (1.1 X) with setae along outer and distal margin; inner ramus with 2 robust setae along outer margin. Telson ( Fig. 6 ) cleft (0.8 X), each lobe pointed at apex, with 1 pair of robust setae distal.

Male, 6 mm. Differing from the female by antennal peduncles with brush setae; urosomite 1 ( Fig. 6 ) dorsal margin produced into a saddle-shaped carina deeper than the equivalent in female; uropod 3 ( Fig. 6 ) rami long and with plumose setae in both margins.

Remarks. Ampelisca anae sp. nov. is closely related to A. anversensis Karaman, 1975 in having pereopods 3 and 4 weakly setose; pereopods 5 and 6 dactylus short and without cusp; pereopod 7 propodus slender and dactylus with a simple setae distal; uropod 2 outer ramus with a long apical robust setae; uropod 3 largely exceeding the end of uropod 2, rami lanceolate, inner ramus with short robust setae. However Ampelisca anae sp. nov. can be distinguished from A. anversensis by: (1) small projection on anterodorsal corner of head; (2) antenna 1 subequal in length to antenna 2 peduncle instead of antenna 1 longer than antenna 2 peduncle; (3) mandible article 2 of palp more stout; (4) pereopod 7 merus not produced anterodistally; (5) uropod 1 rami nacked, without robust setae.

Another species closer to Ampelisca anae sp. nov. is A. aequicornis Bruzelius,1859 that have too a short rostrum in anterodorsal corner of the head; slender pereopod 7 with isquium, merus and carpus unlobed; uropod 3 lanceolate and telson apically acute. However, Ampelisca anae sp. nov. differs from the last species by antenna 1 subequal in length of antenna 2 peduncle, instead antenna 1 subequal in length to antenna 2; long apical robust seta on outer ramus of uopod 2; urosomite 1 without carina instead sinuous dorsal carina and epimeron 3 with a spine in posteroventral corner.

Figures

FIGURE 5. Ampelisca anae sp. nov., holotype female, 5 mm (MNRJ 20525). Scale bars = 0.1 mm, unless indicated otherwise.

FIGURE 6. Ampelisca anae sp. nov., holotype female, 5 mm (MNRJ 20525); paratype male, 6 mm (MNRJ 20531). Scale bars = 0.1 mm.