Creopelates lubangensis, Uyeno, Daisuke, 2015

Uyeno, Daisuke, 2015, Systematic revision of the pennellid genus Creopelates Shiino, 1958 (Copepoda: Siphonostomatoida) and the proposal of a new genus, Zootaxa 3904 (3), pp. 359-386 : 368-374

Creopelates lubangensis n. sp.

( Figs 6 C, D, 9, 10)

Type material. Holotype: postmetamorphic adult female ( NMCR 39115) (dissected), ex Gobiodon rivulatus (Rüppell) ( Perciformes : Gobiidae ), off Pangpang (13°48'N, 120°5'E), Lubang Island, Mindro, South China Sea, Philippines, 5 m depth, 23 May, 2014, leg. A. Ackiss, M. Lane, and D. Uyeno. Paratype: 1 postmetamorphic adult female (UF 40383), collection data same as those of holotype.

Description of postmetamorphic adult female. Body ( Fig. 9 A) 5.24 long, comprising cephalothorax, neck region and trunk; junction of neck and trunk curved. Cephalothorax ( Fig. 9 A–C) ovoid, 0.35 × 0.37, bearing paired rounded antennary process with inner spherical projection and posterolateral lobes both with digitate fringes; ventral surface with irregularly situated small conical protrusions; rostrum ( Fig. 9 D) protruding. Neck region ( Fig. 9 A) narrow, with paired lateral digitate lobes, constriction in anterior ⅓, with multiple posterior protrusions, fringed with series of about ten pairs of finely digitate lobes ( Fig. 9 A); second and third pedigers indistinctly segmented ( Fig. 9 B, C). Trunk ( Fig. 9 A, E) bean-shaped, longer than wide 2.13 × 1.42, with anterior end narrowing slightly towards neck region. Abdomen conical, bearing median depression, located between oviducal pores ( Fig. 9 A, E). Egg-sac uniseriate, coiled ( Fig. 9 A).

Antennule ( Fig. 9 F) unsegmented, bearing 19 setae on anterior margin: distal tip with 10 setae distally, 2 of which share common base, and 1 aesthetasc. Antenna ( Fig. 10 A) 3-segmented, chelate, typical pennellid; proximal segment bearing; middle segment bearing one pointed protrusion on inner medial margin; terminal segment clawlike bearing small basal element on posterior surface. Mouth tube, maxillule, and maxilla located near base of antenna on anterior part of ventral surface of cephalothorax. Maxillule ( Fig. 10 B) comprising one blunt, flanged seta and lobe with two distal setae. Maxilla ( Fig. 10 C) 2-segmented; proximal segment bearing single subterminal pointed process; terminal segment elongate, incompletely subdivided, with distal part ornamented with rows of small spinules. Maxilliped absent.

Legs 1 and 2 ( Fig. 10 D, E) biramous. Legs 3 and 4 ( Fig. 10 F, G) uniramous. Legs 1–4 evenly arrayed along posterior part of cephalothorax to neck region ( Fig. 9 C). Armature formula of legs 1–4 as follows:

Protopod Exopod Endopod Leg 1 1–1 1–1; 7 0–1; 7 Leg 2 1–0 1–1; 7 0–1; 7 Leg 3 1–0 0–0; 6 Absent Leg 4 1–0 0–0; 5 Absent Protopods of legs 1–4 connected to respective intercoxal sclerites ( Fig. 10 D–G).

Attachment site. The cephalothorax and neck of the copepod were embedded in the musculature of the host’s trunk behind the base of the pectoral fin and attached to the vertebrae, while its trunk and egg sacs remained external to the fish’s body wall ( Fig. 6 C, D).

Variability of female morphology. The morphology of the female paratype is as in the holotype. The measurements of the paratype are as follows (n = 1): body length 4.57; cephalothorax length 0.38; cephalothorax width 0.35; trunk length 1.96; trunk width 1.30.

Remarks. Creopelates lubangensis n. sp. differs from C. floridus , C. hoshinoi n. sp. and C. shirakawai n. sp. in having antennary processes with digitate fringes (vs. without digitate fringes). The copepod is distinguishable from C. nohmijimensis by the following character states: antennary processes with inner spherical process (vs. without such a process); the cepholothorax and neck region bearing several small conical processes (vs. without such processes); the neck region bearing multiple protrusions posteriorly (vs. without such protrusions).

Etymology. The specific name “ lubangensis ” refers to the locality where it was found, Lubang Island.

Figures

FIGURE 6. Postmetamorphic adult females of Creopelates shirakawai n. sp. (A, B) and C. lubangensis n. sp. (C, D) attached to their hosts. A, a specimen of Diancistrus fuscus (Fowler) infected by the holotype female, NSMT-Cr 23843; B, coloration in life of holotype attached to host’s body; C, coloration in life of type series, NMCR 39115 and UF 40383, attached to host’s body; D, a specimen of Gobiodon rivulatus (Rüppell) infected by the holotype and the paratype females. Scale bars: A, 5 mm; B, 2 mm; C, 1 mm; D, 3 mm.

FIGURE 9. Creopelates lubangensis n. sp., postmetamorphic adult female, holotype, NMCR 39115. A, habitus; B, cephalothorax and anterior end of neck region, dorsal; C, same, ventral; D, anterior part of cephalothorax with rostrum; E, trunk, ventral; F, left antennule, anterior. Scale bars: A, 1000 µm; B, C, E, 500 µm; D, 100 µm; F, 20 µm.

FIGURE 10. Creopelates lubangensis n. sp., postmetamorphic adult female, holotype, NMCR 39115. A, right antenna, anterior; B, left maxillule; C, left maxilla, anterior; D, right leg 1 with intercoxal sclerite, anterior; E, right leg 2 with intercoxal sclerite, anterior; F, right leg 3 with intercoxal sclerite, anterior; G, left leg 4 with intercoxal sclerite, anterior. Scale bars: A – C, 20 µm; D, E, 50 µm; F, G, 30 µm.