Pontella surrecta Wilson, 1950

Margarethasidabalok, Conni & Mulyadi, Hanung Agus, 2024, A New Species of Pontella Dana, 1846 and New Record of Pontella surrecta Wilson (1950) (Copepoda, Calanoida, Pontellidae) from Indonesian Waters, with Notes on Their Species-Groups, Zootaxa 5512 (4), pp. 553-566 : 562-565

Pontella surrecta Wilson, 1950

( Figs. 5–6 )

Pontella surrecta Wilson, 1950: 299–300 , Figs. 426–427 and 429 (female)

Type locality: northwestern Mindanao , Philippines; Ohtsuka et al., 1987: 568, Figs. 6A–H .

Material examined. Same locality as above. Non type material: ( MZB. Cr.Cop. 209) 10 females (3.20–3.25 mm), 4 males (2.95 mm) .

Female. Body ( Fig. 5a ) robust, relative length of prosome to urosome 4.5:1. Cephalosome separated from Pdg1; Pdg4 and Pdg5 fully separated; posterior corners of prosome produced into asymmetrical, long acuminate processes with globular base in dorsal view, left process longer than right, reaching about distal end of genital compound somite. Cephalosome bluntly triangular and with a pair of lateral hooks and a pair of small lenses located anteriorly. Rostrum bifurcate, symmetrical, thickened basally and tapering distally, directed ventrally, without lens, basal portion lengthened ventrally, reaching level of ventral eye and branched distally into two short spiniform processes.

Urosome ( Figs. 5a–d ) 2-segmented. Genital compound somite much larger than anal somite; asymmetrical with small anterolateral swelling and very large posterodorsal beak-like elevation ( Figs. 5c–d ), latter elevation arising halfway along length of genital compound somite, directed dorsocaudally and tapering into blunt tip reaching as far as two-thirds length of left caudal ramus. Operculum on genital opening elongated to the right shaping spiniform process. Caudal rami asymmetrical, right caudal ramus much broader and longer than left, and completely fused with anal somite; inner margin of each ramus fringed with fine hairs, each ramus with seta I rudimentary and naked, setae II– VI thickened proximally, enlarged portion of seta distinctly shorter than ramus.

P1–P4 as in Pontella mayalibit n. sp. P5 ( Fig. 5e ) asymmetrical; each basis with plumose seta near base of posterior face; left Re 1.4 length of right, smoothly curved inward, tapering to distal point, with 3 minute processes along outer margin, left Ri also longer than right; right Re with 1 minute process on outer margin, Ri short, about 0.31 length of Re; both Ri bifurcated, similar in structure. A1, A2, mandibles, maxillule, maxilla, and maxilliped as in Pontella mayalibit n. sp.

Male. Body ( Fig. 6a ) more compact than that of female. Cephalosome and Pdg1 separated; Pdg4 and Pdg5 also not fused, posterior corners of prosome produced into slightly symmetrical short acuminate processes. Cephalon with a pair of dorsal eye lenses and a pair of cephalic hooks as in female ( Fig. 6b ). Rostrum with asymmetrical short rami and large double convex lenses ( Figs. 6a–b ). Urosome ( Fig. 6c ) 5-segmented; genital somite slightly asymmetrical, left side weakly produced; Ur3 longer than following 2 somites combined; caudal rami asymmetrical, rather elongated, inner margin of each ramus fringed with fine hairs, each ramus with seta I rudimentary and naked, setae II– VI without proximal thickening.

Right A1 ( Fig. 6d ) geniculate, left one resembling that of female. Fusion pattern and setal formula as follows: I, 3 + ae; II– IV, 4 + ae; V –IX, 10 + 3ae; X– XIV, 10 + 3ae; XV – XVI, 4 + 2ae; XVII, 2 + ae; XVIII, 2 + ae; XIX, 1 + ae; XX, 1 + p (process); XXI – XXIII, 2 + 3p + ae; XXIV – XXVI, 6 + ae; XXVII – XXVIII, 4 + ae. Fused segment XV – XVI with very strong hooked spine, segment XX with toothed ridge provided with serrated denticles; compound segments XXI – XXIII provided with falcate process distally and 2 toothed plates, proximal plate with acuminate teeth and distal one with lamelliform teeth.

All other appendages except for P5 similar in structure to those of female.

P5 ( Figs. 6e–f ) uniramous, asymmetrical; each basis with plumose seta; right leg with Re1 (chela) with a slender and elongated thumb, curved inward; concave surface with 1 large digitiform process with knob-like process and naked seta at base; Re2 (finger) slender and elongated almost as long as left leg, curved outwards at middle point, tip slightly expanded, lamelliform with 4 short setae present along concave face. Left leg, Re1 with 1 minute spine at inner margin; Re2 carrying hirsute patch, with naked seta at 1/3 length and serrated spine medially, ending in stout flagelliform process and 2 unequal spine-like process.

Remarks. Our character comparison on Pontella specimens from coastal waters of Indonesia with description and figures of Pontella alata by Wilson (1950) is in accordance with Ohtsuka et al. (1987). The female of Pontella surrecta is very close to that of P. rostraticauda by sharing morphologically similar appendages except for fifth leg ( Ohtsuka et al. 1987). Indonesian specimens of Pontella surrecta have the same beak-like posterodorsal process as in Pontella rostraticauda which never reaches the end of the left caudal ramus, while in P. surrecta from Papua New Guinea the size and the shape of the process vary, either it totally covers the left caudal ramus or not reaching the end ( Ohtsuka et al. 1987). The female fifth leg of Pontella surrecta from Mayalibit has 3 minute prominences on the left and 1 very fine prominence on the right (vs. 2 minute prominences on the left and 1 or 2 very fine prominences on the right on Ohtsuka’s et al. 1987 specimens). More character differences are presented in Table 1.

Pontella surrecta belongs to the P. alata species-group established by Fleminger (1957), which is now composed of four species: P. alata , P. surrecta , P. rostracticauda and P. mayalibit n. sp, with the distribution spreads in the Indo-West Pacific region. Previously, Wilson (1950) described Pontella surrecta on the basis of specimens from off Jolo, the Philippines. Nowadays, Pontella surrecta is widely recorded from Indonesian waters, Indian seaside of southern Java (Sempu and Panaitan Islands), Java Sea (Jakarta Bay, off Pekalongan and off Surabaya), Lombok Strait, Manado Bay, Ternate and Mayalibit Bay (present record).

Figures

FIGURE 5. Pontella surrecta. MZB.Cr.Cop. 209. ♀. a. whole animal, dorsal view; b–c. Pdg5 and urosome, dorsal view; d. urosome, ventral view; e. P5.

FIGURE 6. Pontella surrecta, MZB.Cr.Cop. 209. ♂. a. whole animal, dorsal view; b. cephalon, lateral view; c. Pdg5 and urosome, lateral view; d. right antennule; e. right P5; f. left P5.