Brasilibathynellocaris panamericana, (NOODT, 1962)

Corgosinho, Paulo H. C., Arbizu, Pedro Martínez & Dos Santos-Silva, Edinaldo N., 2010, Revision of Brasilibathynellocaris Jakobi, 1972 (Copepoda: Harpacticoida: Parastenocarididae) with redefinition of the genus, Zoological Journal of the Linnean Society 159 (3), pp. 527-566 : 539-544

BRASILIBATHYNELLOCARIS PANAMERICANA ( NOODT, 1962) ( FIGS 11–13 )

Parastenocaris panamericana Noodt – Noodt (1962: 228); Löffler (1981).

Brasilibathynellocaris panamericana (Noodt) – Jakobi (1972a).

Parastenocaris panamericana panamericana Noodt – Rouch (1986), Dussart & Defaye (1990).

Material examined: Syntypes from sample S 176 ( Noodt, 1962); from this sample, Noodt prepared four slides now stored at DZMB (Noodt collection, box 6, slide nos. 37–40), all of them carrying more than one individual and both sexes; we were unable to discern unequivocally which animal was actually drawn by Noodt. Redescription is based on dissected males on slides 38–40 and on females on slides 37, 39, and 40 .

Collecting locality: El Salvador, groundwater in bank of Rio Guasala (next to Jiboa river) on road between San Salvador and Zacatecoluca. Note that Noodt (1962: 228) called this locality (of sample S 176) the ‘locus typicus’, but that this did not explicitly exclude the many additional specimens he listed from other samples from his type series of Parastenocaris panamericana ( ICZN, 1999: Art. 72.4.6). Consequently, all those specimens are syntypes of equal nomenclatural standing, and all corresponding localities together form the type locality ( ICZN, 1999: Art. 76.1). Description

Male: Habitus in dorsal view and length as in Noodt (1962: 229, fig. 12). Rostrum not fused to cephalothorax, with a wide base and two sensilla on tip. Cephalothorax with dorsal integumental window, second to fifth urosomites with one dorsal integumental window each ( Noodt, 1962, loc. cit.). Telson smooth ( Fig. 11A ); anal operculum smooth and slightly concave ( Noodt, 1962: 229, fig. 2). Furca ( Fig. 11A ) with six visible setae and a distal pore on outer margin; setae I and III inserted proximally to the middle of furca, anterior to seta VII; seta II reduced or absent, not visible; seta IV subdistal, inserting dorsally, on outer margin of furca; setae V long ( Noodt, 1962: 229, fig. 1), inserting on distal margin of furca; seta VI shorter than seta V inserting beneath it; seta VII of about same size as seta VI, socketed at basis and inserting dorsally, on inner margin of furca. A1, A2, and mouthparts as in B. brasilibathynellae . Praecoxa of legs 1–4 is a distinct and relatively large triangular section adjacent to the outer proximal corner of coxa ( Fig. 12A–D ). Leg 1 ( Fig. 12A ) coxa unarmed; basis with outer seta and one pore on anterior outer margin, three spinules on outer margin, and a row of eight small spinules distally, between endopod and exopod. Endopod twosegmented; enp-1 as long as the combined length of first two exopod segments, with two outer rows of spinules and a distal row of spinules on inner margin; enp-2 with one outer spine, one geniculate seta, and a posterior hyaline frill. Exopod three-segmented, exp-1 with outer spine, exp-2 unarmed, exp-3 with two outer spines and two geniculate setae of different lengths. Leg 2 ( Fig. 12B ) coxa unarmed, with row of small spinules on posterior margin and row of spinules on anterior margin; basis without outer seta, with outer pore and one row of spinules on outer margin; exopod three-segmented, exp-1 with a long outer spine and a hyaline frill on distal inner corner; exp-2 without armature and with two divergent rows of long spinules arranged distally; exp-3 with three setae of different lengths, distal hyaline frill at inner corner and row of long spinules on outer distal margin; endopod one-segmented, shorter than exp-1, with a row of spinules along inner margin, one long and subdistal spinule on each side of segment, two long spinules proximally inserted on outer margin and a distal seta. Leg 3 ( Fig. 12C ) coxa unarmed; basis with an outer seta (broken in the illustration), an inner strong (hook-shaped) spinule on proximal portion and two rows of spinules of different sizes near insertion of endopod; endopod represented by a slender seta; exopod inwardly curved, strong, ending in a long forceps formed by long apophysis and thumb (both with a hyaline margin); proximally with a hyaline ‘cushion’ on inner margin. Leg 4 ( Fig. 12D ) coxa with two long and strong spinules on anterior margin; basis quadratic, with an outer seta and an outer pore; exp-1 reduced in length and with an invagination on proximal inner corner; anteriorly with a row of four long spinules; outer margin strongly ornamented and with an outer spine; exp-2 unarmed, with a transversal row of long spinules distally inserted on outer corner and a distal row of small spinules on inner corner; exp-3 with two distal setae of different lengths and two big spinules distally inserted on outer margin; endopod falciform, with a serrated lamella on outer margin and a subdistal hyaline ‘tongue’ on inner margin. Leg 5 trapezoid, with an inner process, an intercoxal plate, an outer basal seta, and two distal setae inserted on outer margin ( Figs 11D , 12E ); in different shape on Figure 11C because of lateral displacement of the limbs. Leg 6 is an unarmed, rounded, and asymmetrical operculum covering the genital aperture ( Fig. 11C ), appearing as a triangular plate in lateral view ( Fig. 11D ).

Female: Sexually dimorphic in A1, legs 2–5, genital somite and furca. Length as in Noodt (1962). Integumental windows as in B. brasilibathynellae . Telson smooth, anal operculum smooth and slightly concave ( Noodt, 1962: 229, fig. 1). Furca as in male, but with seven visible setae; setae I– III inserted proximally to the middle of furca, anterior to seta VII; seta II very reduced. A1 seven-segmented ( Fig. 13D ), not geniculate; armature beginning with proximal segment as follows: 0/4/5/2 + Ae/1/1/9 + Ae. A2 and mouthparts as in male. Praecoxa of legs 2–4 is a distinct and relatively large triangular section adjacent to the outer proximal corner of coxa ( Fig. 13A–C ). Leg 1 as in male. Leg 2 ( Fig. 13A ) coxa unarmed, with one row of small spinules on anterior margin; basis without outer seta, with outer pore and ornamented with one row of spinules on outer margin; exopod three-segmented, exp-1 with long outer spine and with a hyaline frill on the distal inner corner, exp-2 and exp-3 as in male; endopod one-segmented, less ornamented than in male. Leg 3 ( Fig. 13B ) coxa unarmed, with a posterior and an anterior row of spinules; basis with a long outer seta, an outer pore, a row of spinules between outer seta and exopod, and a row of spinules before insertion of endopod; endopod represented by a short segment with a subdistal spinule; exopod twosegmented; exp-1 with an outer spine and two transversal inner rows of spinules, inserted one distally and subdistal; exp-2 with two apical setae, an hyaline frill on distal inner corner and an outer subdistal spinule. Leg 4 ( Fig. 13C ) coxa unarmed; basis with an outer seta, an outer pore, and a row of spinules near insertion of endopod; endopod one-segmented, longer than exp-1, with a row of transverse spinules medially inserted, probably delineating original separation between endopod and pinnate distal seta, now incorporated into segment, and two basal spinules; exopod three-segmented, exp-1 normally developed, with an outer spine and a hyaline frill on distal inner corner; exp-2 and exp-3 as in males. Leg 5 rectangular, with an inner process, an intercoxal plate, an outer basal seta and three distal exopodal setae ( Noodt, 1962: 229, fig. 10). Genital field as illustrated in Figure 13E . Genital operculum formed by two lateral and unarmed plates covering the gonopores. Single medially located copulatory pore.

Figures

Figure 11. Brasilibathynellocaris panamericana. A, male telson, lateral. B, ‘forma truncata’, female telson, lateral. C, ventral view of the first and second urosomites of male. D, lateral view of the first and second urosomite of male. Scale bar 1 (for A–B) = 50 Mm. Scale bar 2 (for C) = 20 Mm. Scale bar 3 (for D) = 20 Mm.

Figure 12. Brasilibathynellocaris panamericana, male. A, leg 1. B, leg 2. C, leg 3. D, leg 4. E, leg 5. Scale bar = 20 Mm.

Figure 13. Brasilibathynellocaris panamericana, female. A, coxa, basis, endopod, and exopod 1 of leg 2. B, leg 3. C, coxa, basis, endopod, and exopod 1 of leg 4. D, antennule. E, female genital field. Scale bars 1 (for A–C), 2 (for D), 3 (for E) = 20 Mm.