Remaneicaris siankaan, Corgosinho, Paulo Henrique C., Mercado-Salas, Nancy F., Arbizu, Pedro Martínez, Silva, Edinaldo Nelson Dos Santos & Kihara, Terue C., 2017

Corgosinho, Paulo Henrique C., Mercado-Salas, Nancy F., Arbizu, Pedro Martínez, Silva, Edinaldo Nelson Dos Santos & Kihara, Terue C., 2017, Revision of the Remaneicaris argentina - group (Copepoda, Harpacticoida, Parastenocarididae): supplementary description of species, and description of the first semi-terrestrial Remaneicaris from the tropical forest of Southeast Mexico, Zootaxa 4238 (4), pp. 499-530 : 515-524

Remaneicaris siankaan sp. nov.

( Figures 8–15 )

Holotype: One dissected male mounted on 3 slides (ECO- CH-Z-09331). Paratypes: allotype 1 ♀ on 1 slide; 4 ♂♂ dissected mounted in individual slides. 60♀ ♂ preserved in 96% ethanol and deposited at the Zooplankton Collections of El Colegio de la Frontera Sur in Chetumal, Mexico (No: ECO- CH-Z-09332). Coll. by Nancy F. Mercado-Salas.

Etymology. The species name is noun in apposition that refers to Sian Ka´an Biosphere Reserve in which the specimens were collected; Sian Ka´an in Mayan language means “heaven’s door” or “place where heaven begins”.

Type locality. Aguada Vigía Chico (S1), Sian ka´an Biosphere Reserve, Quintana Roo, Mexico (19°47´00.72´´ N, 87°36´37.1´´W), coll. 20. Sept. 2014 by Nancy F. Mercado-Salas. Samples 96% ethanol preserved. Animals were sorted out from water collected in the leaves of the bromeliad Tillandsia dasyliriifolia Baker. Additional material in Table 1 .

Male. Habitus ( Fig. 8 A, B and Fig 13 B). Length 355µm (measured from tip of rostrum to distal rim of telson). Rostrum not fused to Cph. Cph with 1 integumental window and 1 dorsal pore. One dorsal pore on first and 3rd thoracic somites. Urs-2 with 2 integumental pores and 1 dorsal integumental window (slightly extended laterally). Urs5 with 1 dorso lateral integumental window and ornamented with uneven cuticle over the entire surface, including integumental window. Telson ( Fig. 8 A, B, D and Fig. 14 D, F) with dorsal, continuous row of spinules near to anal operculum; telson ornamented with uneven cuticle over the entire surface. Anal operculum convex, flanked by4 spinules on each side. Furca shorter than telson 2.4 times longer than wide, proximally convex on inner margin, Setae I–III and VII located approximately at ½ of total length, opposite to each other; seta II–IV approximately of same size, seta I about half of length of setae II–IV; seta V the longest, seta VII longer than setae II–IV –approximately 1.7 times longer. Strong spinules on proximal margin of furca. A1 ( Fig. 9 A, Fig. 15 A and D): 8-segmented, haplocer, prehensile, geniculation between segments 3–4 and 6–7;armature formula 0/5/1/1/3+Ae/1/?/7+Ae. A2 ( Fig. 9 B, C): Allobasis with 2 rows of spinules on frontal surface. Exp 1-segmented bearing 1 strong seta, 1-segmented enp with 7 setae and row of small spinules on insertion of apical setae. Mx 1 ( Fig. 9 D): precoxal arthrite with 4 elements (3 claw-like spines and one slender seta), coxa with one seta, basis with 2 endites with 1 and 2 setae (1 seta missing); enp and exp absent. Mx 2 ( Fig. 9 E): precoxa and coxa fused, coxa with 2 endites, proximal endite with 2 setae, distal endite with 2 slender setae, basis with endite drawn into strong chitinized claw, enp 1-segmented, bearing 2 distal setae equal in size. Mxp ( Fig. 9 F): subchelate, composed of syncoxa, basis, 1- segmented enp and 1 claw-like apical seta. Claw-like apical seta ornamented with small spinules on inner margin. P1 ( Fig. 10 A, B): basis with short outer seta, row of spinules on insertion of outer seta; distally with 2 spinules at base of enp. Enp 2-segmented, enp-1 1.3 times longer than enp2 and slightly longer than exp-1 and exp-2 together, outer margin with 2 strong spinules at proximal 1/3 and 2 strong unequal spinules at distal 1/3; diagonal row of spinules at distal 1/3, distal hyaline frill; enp-2 with 2 spinules on medial outer margin, inner margin with group of spinules that extends on caudal surface, apical edge with 1 unipinate outer spine and 1 geniculated seta, about 2.7 times longer than outer spine. Exp 3-segmented, exp-1 with 1 unipinate outer spine, outer margin ornamented with 1 strong spinule at middle margin and two smaller spinules at distal 1/3, distal hyaline frill; exp-2 ornamented on outer edge with 1 strong spinule at distal 1/3, two small spinules located proximally to strong spinule and 4 small distal spinules; exp-3 with 4 unipinated elements: 2 outer spines (1 lateral and 1 apical) and 2 geniculated apical setae, innermost the longest one.P2 ( Fig. 10 C,15E): basis without outer seta, with an anterior pore relatively close to outer margin, row of spinules on outer margin and row of small spinules near to enp insertion. Enp 1 – segmented, about 0.6 times as long as exp-1, armed with one long apical seta, two strong apical spinules and 2 outer spinules on distal half. Exp 3-segmented, exp-2 and exp-3 about same length, exp-1 elongated, approximately FIGURE 12. Remaneicaris siankaan sp. nov. female. A, P1; B,Enp P1; C, P2; D, enp P2; E, P3; F, P4.

1.6 times longer than exp-2 and exp 3. Exp-1 with 1 outer distal spine, outer margin ornamented with three small spinules and two long strong spinules at proximal 1/3 and 2 strong spinules at distal 1/3, distal hyaline frill; exp-2 without outer spine but ornamented with 3 strongly chitinized spinules, 1 at middle margin and 2 apical, distal hyaline frill; exp-3 with 3 not simetrically bipinnate elements on apical edge, 1 short outer, spine; 1 long medial seta, and 1 longer inner, seta, inner seta the longest one. P3 ( Fig. 10 D, E and Fig. 15 B, C): coxa with row of small spinules near insertion of basis on outer margin, basis with long outer seta. Enp 1-segmented, approximately 1/6 of total length of exp, bearing a small apical seta. Exp 1-segmented, elongated with 5 strong chitinized spinules at proximal half and 3 strong chitinized spinules on distal 2/3, 1 modified spinule on distal 1/3, modified spinule with hyaline lamella along anterior half, appearing as a hitherto unique bifid structure; apophysis triangular, ending in a blade-like hyaline lamella, thumb long, twice curved inwards, ending in a rounded tip. P4 ( Fig. 10 F and Fig. 15 F):, basis with 1 outer seta and row of small spinules on its insertion. Enp 1-segmented, about 0.6 times as long as exp- 1, oval-shaped covered with numerous long spinules along inner margin, outer margin bare. Exp 3-segmented, tapering progressively, exp-1 and exp-3 about the same length, exp-2 slightly shorter (0.7 times as long as exp-1 and exp-3); exp-1 with 1 bipinnate outer spine, outer margin with 2 strong spinules at proximal 1/3 and 2 strong spinules near to outer spine insertion, hyaline distal frill, exp-2 bearing 1 strong medial spinule on outer margin and 1 strong spinule at distal 2/3, hyaline distal frill; exp-3 with 1 long bipinate apical seta (about 1.7 times longer than exp-3) and 1 seta, inserted at distal 2/3 of outer margin, outer margin ornamented with two strong spinules located at ½. P5 ( Fig. 8 C and Fig. 14 C): 1-segmented, subcuadrated, 2.5 times longer than wide; without intercoxal plate and with small distal process on inner margin; all setae inserted distally. Innermost seta long, two medial setae about the same length, outermost seta the longest one, (1.7 times longer than innermost seta and 5.7 times longer than medial setae).

Female: Habitus ( Fig. 13 A). Sexually dimorphic in A1, P3, P4, P5 and genital field. Rostrum as in male. Integumental windows in cph,urs-2 and4 ( Fig. 13 A, 14A). Telson and furca as in male ( Fig. 11 B, 14A). A1 ( Fig. 11 C): 7-segmented; number of setae beginning at proximal segment: 0/4/5/2+Ae/0/1/7+Ae. A2 ( Fig. 11 D): as in male but weakly ornamented. P1 (Fig. 12A, B) and P2 (Fig. 12 C, D) as in male. P3 (Fig. 12E): basis with 1 outer seta and row of spinules near to insertion of enp; enp 1-segmented and spiniform, with 1 strong spinule at half outer margin and distal spinules. Exp 2-segmented, exp-1 1.2 times longer than exp-2, exp-1 bearing 1apical spine on outer margin and ornamented with two unequal spinules at proximal 2/3 and three unequal spinules at distal 2/3, hyaline distal frill; exp-2 with 1 long bipinated apical seta and 1 shorter seta displaced medially on outer margin, outer margin ornamented with 2 spinules, 1 at ½ and 1 at distal 2/3; P4 (Fig. 12F): exp as in male, weakly ornamented, with enp not oval-shape and bearing stronger spinules. P5 ( Fig. 11 A and Fig. 14 B): 1-segmented, subcuadrated, 2.5 times longer than wide; without intercoxal plate and with small distal process on inner margin; all setae inserted distally. Innermost seta the longest one, two medial setae about the same length, outermost seta long, outermost seta 0.6 times as long as innermost seta and 2.5 times longer than medial setae). Genital field ( Fig 11 A) is 1 horizontal slit on proximal margin of genital double somite ( Fig. 14 B).

Figures

FIGURE 8. Remaneicaris siankaan sp. nov. male. A, habitus, lateral view; B, habitus, dorsal view; C, P 5; D, telson and furca, dorso-lateral view Scale bars A, B = 100 µm, C, D = 50 µm.

FIGURE 9. Remaneicaris siankaan sp. nov. male. A, A 1; B, A 2, frontal view; C, A 2 allobasis, caudal view; D, Mx 1; E, Mx 2; F, Mxp. Scale bar = 25 µm.

FIGURE 10. Remaneicaris siankaan sp. nov. male. A, enp and exp P 1; B, coxa, basis and coxal sclerite P 1; C, P 2; D, P 3; E, P 3; F, P 4. Scale bar = 50 µm.

FIGURE 11. Remaneicaris siankaan sp. nov. female. A, P 5 and Ur- 1, genital double somite; B, telson and furca, dorsal view; C, A 1; D, A 2. Scale bars = 50 µm.

FIGURE 14 (CLSM _ Plate 2). Remaneicaris siankaan sp. nov. three-dimensional representation (Drishti software) based on confocal laser scanning microscopy images. A, B, female. C – F, male. A, Urs- 4, telson and furca, lateral view; B. P 5 and Urs- 1, genital double somite, lateral view; C, Urs- 1 – 2, P 5 and P 6, lateral view; D, Urs- 5, telson and furca, lateral view; E, Urs- 5, telson and furca, ventral view; F, Urs- 5, telson and furca, dorsal view Scale bars = 50 µm.

FIGURE 15 (CLSM _ Plate 3). Remaneicaris siankaan sp. nov. three-dimensional representation (Drishti software) based on confocal laser scanning microscopy images. Male. A, Prosome, lateral view; B, exp P 3; C, P 3; D, A 1 and A 2; E, P 2; F, P 4. Scale bars = 50 µm. 3