Acanthoplacatus puelli, Ernst & Jones & Whittington, 2001

Ernst, Ingo, Jones, Malcolm K. & Whittington, Ian D., 2001, A new genus of viviparous gyrodactylid (Monogenea) from the Great Barrier Reef, Australia with descriptions of seven new species, Journal of Natural History 35 (3), pp. 313-340 : 329-331

publication ID	https://doi.org/10.1080/002229301300009568
DOI	https://doi.org/10.5281/zenodo.4757232
persistent identifier	https://treatment.plazi.org/id/03E66075-FFE4-FFDC-A0D3-3403FD156330
treatment provided by	Carolina
scientific name	Acanthoplacatus puelli
status	sp. nov.

Treatment

Acanthoplacatus puelli View in CoL sp. nov.

( Figures 3 View FIG , 8A View FIG -D)

Type host. Siganus puellus (Schlegel, 1852) (Siganidae) .

Type locality. Heron Island , Great Barrier Reef , Queensland, Australia.

Site on host. This species was found most frequently on the dorsal and pectoral fins (table 1).

Holotype. QM G215985 .

Paratypes. QM G215986-7 .

Etymology. Named after the type host Siganus puellus .

Infection details. Prevalence 83%, six fi sh examined, LCF 204 mm (168- 251 mm); mean intensity 118 (10-468), fi ve fi sh examined, LCF 211 mm (180- 251 mm).

Description. Sclerite measurements taken from 14 worms mounted in Malmberg’s fi xative. Measurements of other organs taken from nine worms stained with Ehrlich’s haematoxylin. Numerous live worms examined for structure of soft body parts and excretory system. Total length 262 (246-293, n = 6), maximum width 59.5 (54-64, n = 8) at level of uterus when embryo contained within or testis for worms with small embryo (figure 8A). Hamulus length 39 (37.5-40.5, n = 13); hamulus point length 17.5 (15-20, n = 13); hamulus root length 20 (17-22.5, n = 13); hamulus shaft length 28.5 (26.5-29, n = 13). Hamulus shafts with distinct longitudinal depression anteroventrally. Dorsal root tissue cap length 8 (7-9.5, n = 13), width 3.5 (3-4, n = 13). Ventral bar simple, variable in shape (fi gures 3, 8D). Ventral bar 5 (5-6, n = 12) long and 14 (13-16, n = 12) wide. Length of ventral bar membrane 15.5 (15-20, n = 12). Total length of ventral bar and membrane 22.5 (20-25, n = 12). Transition between ventral bar and ventral bar membrane not distinct. Marginal hooks small with hook point extending slightly past toe; total length of marginal hook 27.5 (27-29, n = 12); length of sickle 3.5 (3-4, n = 11); length of handle 24.5 (23.5-26, n = 11) (figure 8B).

Gland cells, posterolateral to pharynx range from minimum diameter of 9.5 (7-12, n = 7) to maximum diameter of 12.5 (11-15, n = 7). Anterior lobe of pharynx 27 (24-30, n = 9) wide, posterior lobe 30.5 (27-34, n = 9) wide. Gut caeca extend posteriorly lateral to uterus, terminating posterior to testis. Male copulatory organ with one large, two moderate and six small spines (1+ 2+ 6) (figure 8C). Male copulatory organ 13 (11-14, n = 4) long, 13 (12-14, n = 4) wide. Developing sclerites of F2 embryos may be visible within large F1 embryos; no sclerites of F3 embryos visible. Oocyte 14 (8-23, n = 8) long, 20.5 (14-34, n = 8) wide, contained within ECFR. Testis 11 (3-18, n = 8) long; 15 (6-23, n = 8) wide. Five cells surround posterior portion of each gut caecum and single cell lies medially near posterior terminations; cells range from minimum diameter of 12.5 (11-14, n = 9) to maximum diameter of 16.5 (15-19, n = 9). Two anterior-most cell pairs and posterolateral cell pair ventral to gut; remaining two cell pairs and single medial cell dorsal to gut (figure 8A).

Comments. The size and shape of the haptoral sclerites in Acanthoplacatus puelli sp. nov. is similar to A adlardi sp. nov and A. shieldsi sp. nov. Acanthoplacatus puelli sp. nov. differs from A. adlardi sp. nov. as described above for that species. Acanthoplacatu s puelli sp. nov. has smaller marginal hook length and marginal hook handle length than A. shieldsi sp. nov. although 0.5 m m overlap occurs for both characters. Acanthoplacatus puelli sp. nov. differs from all other species by having a male copulatory organ with a 1+ 2+ 6 con fi guration.