Bonnierella campensis, Souza-Filho & Serejo, 2014

Souza-Filho, Jesser F. & Serejo, Cristiana S., 2014, On the phylogeny of Ischyroceridae (Amphipoda, Senticaudata, Corophiida), with the description of a new genus and eight new species from deep-sea Brazilian waters, Zoological Journal of the Linnean Society 170 (1), pp. 34-85 : 49-53

BONNIERELLA CAMPENSIS SP. NOV. ( FIGS 8–10 )

Bonnierella sp. Souza-Filho & Serejo, 2010a: 180.

Material examined

Holotype: male (3.7 mm), OCEANPROF I, BC-SUL, #79, Campos Basin , Rio de Janeiro, Brazil, 22°20′44.82″S, 40°01′24.72″W, 775 m, 21 November 2002, MNRJ 21218 .

Paratypes: One female (3.3 mm) (dissected and drawn), OCEANPROF I, BC-SUL, # 79, Campos Basin , Rio de Janeiro, Brazil, 22°20′44.82″S, 40°01′24.72″W, 775 m, 26 November 2002, MNRJ 21484 . One female, OCEANPROF I, BC-SUL, # 74, Campos Basin , Rio de Janeiro, Brazil, 22°28′3.24″S, 40°09′23.22″W, 750 m, 12 December 2002, MNRJ 21215 . One female, OCEANPROF I, BC-NORTE, # 59, Campos Basin , Rio de Janeiro, Brazil, 21°53′59.22″S, 39°55′30,66″W, 750 m, 1 July 2003, MNRJ 21216 . One female, OCEANPROF II, BC #44 , BC-NORTE , Campos Basin , Rio de Janeiro, Brazil, 22°11′27″S, 39°54′45″W, 749 m, 26 November 2002, MNRJ 21217 . One male, OCEANPROF I, BC-NORTE, # 59, Campos Basin , Rio de Janeiro, Brazil, 21°53′59.22″S, 39°55′30.66″W, 750 m, 12 December 2002, MNRJ 21219 . One male, OCEANPROF II, BC-NORTE , # 54, Campos Basin , Rio de Janeiro, Brazil, 21°57′23.58″S, 39°56′0.42″W, 750 m, 29 July 2003, MNRJ 21220 . One male and one female, OCEANPROF II, BC- SUL, #79, Campos Basin , Rio de Janeiro, Brazil, 22°20′44.82″S, 40°01′24.72″W, 750 m, 21 June 2003, MNRJ 21221 . One female, OCEANPROF I, BC-NORTE, # 60, Campos Basin , Rio de Janeiro, Brazil, 21°53′40.92″S, 39°51′42.60″W, 1050 m, 12 December 2002, MNRJ 21228 . One female, OCEANPROF II, BC-SUL , # 59, Campos Basin , Rio de Janeiro, Brazil, 21°52′59.2″S, 39°55′32.2″W, 750 m, 29 June 2003, MNRJ 19049 . One male and one female, OCEANPROF II, BC-SUL , # 74, Campos Basin , Rio de Janeiro, Brazil, 22°28′02.22″S 40°09′23.52″W, 750 m, 18 June 2003, MNRJ 21230 . One male, OCEANPROF I, BC-SUL, # 84, Campos Basin , Rio de Janeiro, Brazil, 22°26′41.4″ S 39°58′53.28″ W, 1050 m, 20 June 2003, MNRJ 21232 .

Etymology

The name campensis refers to the type locality, Campos Basin , Rio de Janeiro, Brazil .

Type locality

Campos Basin, Rio de Janeiro, Brazil.

Diagnosis

Maxilliped outer plate ovate, extending to two-thirds of palp article 2; palp 4-articulate, article 4 longer than article 3, with apical nail. Gnathopod 2 carpus triangular and short; propodus massive, 2.6 × carpus length, palm shorter than posterior margin with two processes, first process proximal and tridentate and second process truncate, separated by a U-shaped excavation followed by a concave crenulated portion, palmar corner defined by a short acute spine, facial margin with two pairs of robust setae; dactylus stout with a spine on inner margin. Uropod 1 peduncle interamal process about one-fifth of peduncle length; rami with one apical seta. Uropod 2 interamal process rudimentary; rami with one apical seta. Uropod 3 peduncle 1.4 × outer ramus length, outer ramus with four subapical tiny spines. Telson triangular with two short subapical setae.

Description

Based on holotype male (3.7 mm), MNRJ 21218. Head as long as pereonites 1 and 2 together; lateral cephalic lobe acute; eyes absent; anteroventral margin strongly recessed. Antennae 1 and 2 missing. Epistome acute and turned upwards. Mandible lacinia mobilis asymmetrical; palp article 2 longer than article 3, with 11 slender setae; article 3

Information from the literature and from observed material.

spatulate, with long facial and long setae. Maxilla 1 inner plate with one long seta; outer plate with ten robust setae; palp longer than outer plate, with four robust apical setae and one slender facial seta. Maxilliped inner plate rectangular, with three apical short robust setae; outer plate ovate, extending to two-thirds of palp article 2; palp 4-articulate, article 4 longer than article 3 with apical nail. Upper lip, lower lip, and maxilla 2 with basic characters for the genus.

Coxae 1–7 wider than long. Coxa 2 wider than other coxae, with seven short setae on distal margin. Coxae 5 and 6 excavate distally. Gnathopod 1 basis slender, without setae; propodus subovoid, slightly longer than carpus, palm evenly rounded and crenulated; dactylus fitting propodus. Gnathopod 2 basis, anterior margin with some sparse setae, anterodistal angle with a short process, posterior margin weakly convex; carpus triangular and short; propodus massive, 2.6 × carpus length, palm shorter than posterior margin, with two processes, first process proximal and tridentate and second process truncate, both separated by a U-shaped excavation followed by a concave crenulated portion, palmar corner defined by a short acute spine, facial margin with two pairs of robust setae; dactylus stout, with a spine on inner margin. Pereopods 3 and 4 similar in shape and length; basis long and slender, as long as merus and carpus together, both anterior and posterior margins without setae; merus with anterior margin produced; propodus longer than carpus; dactylus slightly shorter than propodus. Pereopods 5–7 missing.

Epimera 1–3 rounded. Uropods 1 and 2 reaching equally apex of uropod 3. Uropod 1 peduncle inner margin with four short robust marginal setae and one distal seta, outer margin with only one marginal seta; interamal process about one-fifth peduncle length; rami with one apical seta; inner ramus longer than outer ramus, with one short robust seta about midlength of ramus; outer ramus naked. Uropod 2, inner margin with one short robust marginal seta and one robust apical seta; interamal process rudimentary; rami with one apical seta; inner ramus longer than outer ramus, with one single short robust

seta about midlength of ramus. Uropod 3 peduncle

1.4 × length of outer ramus, with three robust marginal setae; inner ramus longer than outer ramus, naked; outer ramus with four tiny subapical spines. Telson triangular, with two short subapical setae.

Sexually dimorphic characters

Females differ from males by the more-inflated body, and in the shape of gnathopod 2, in which the propodus is 1.9 × length of the carpus, and the palm is evenly rounded, with two crenulated portions separated by a shallow oblique excavation with a small spine.

Additional description

Based on female paratype (3.3 mm), MNRJ 21484. Pereopod 5, basis subrectangular; merus longer than carpus, with posterior margin produced; carpus 0.37 × propodus length; propodus long; dactylus about one-quarter of propodus length. Pereopod 6, basis rectangular; merus shorter than basis, with posterior

margin produced; carpus 0.57 × propodus length;

propodus long; dactylus more than one-thrid propodus length. Pereopod 7, basis rectangular, posterior margin with three slender setae; merus longer than basis; propodus long; dactylus more than onethird propodus length.

Remarks

Bonnierella campensis sp. nov. shows some similarities with B. lapisi , such as the shape of gnathopods 1 and 2 in the male, and the basis of pereopods 5 and 6 rectangular; however, B. campensis sp. nov. has the palm of gnathopod 2 with two blunt processes, and the palmar corner is defined by a short process in the male, whereas B. lapisi has two acute processes and the palmar corner is defined by a large acute process. Also, B. campensis sp. nov. has less setose rami of uropods 1 and 2, and the outer rami of uropod 3 measures 0.7 × the peduncle length. Moreover, the female gnathopod 2 of B. campensis sp. nov. lacks an excavation on the palm.

Bonnierella campensis sp. nov. is also closely related to B. californica , in the shape of gnathopods 1 and 2, basis of pereopods 5 and 6, and uropods 1 and 3. Nevertheless, B. campensis sp. nov. has gnathopod 1 sparsely setose, with the dactylus short, both margins of the basis of pereopod 3 sparsely setose, the tip of the telson acute, and the rami of uropod 3 elongate. Additionally, B. campensis sp. nov. differs from all other species of the genus in having an elongate and ovate outer plate of the maxilliped ( Table 5).

Geographic distribution

South-western Atlantic: Campos Basin, Rio de Janeiro, Brazil.

Figures

Figure 8. Bonnierella campensis sp. nov. Holotype: male (3.7 mm), OCEANPROF I, BC-SUL, #79, 775 m, 21 November 2002, MNRJ 21218. Scale bars: 0.1 mm.

Figure 9. Bonnierella campensis sp. nov. Holotype: male (3.7 mm), OCEANPROF I, BC-SUL, #79, 775 m, 21 November 2002, MNRJ 21218. Paratype: female (3.3 mm) OCEANPROF I, BC-SUL, #79, 775 m, 26 November 2002, MNRJ 21484. Scale bars: 0.1 mm.

Figure 10. Bonnierella campensis sp. nov. Holotype: male (3.7 mm), OCEANPROF I, BC-SUL, #79, 775 m, 21 November 2002, MNRJ 21218. Paratype: female (3.3 mm) OCEANPROF I, BC-SUL, #79, 775 m, 26 November 2002, MNRJ 21484. Scale bars: 0.1 mm.