Laqueusplana megala ( Marcus, 1952 ) Rodríguez & Grande & Bulnes & Almon & Perez & Noreña, 2017

Rodríguez, Jorge, Grande, Cristina, Bulnes, NataliaVeronica, Almon, Bruno, Perez, Jacinto & Noreña, Carolina, 2017, Systematic revision of the family Pleioplanidae Faubel, 1983 (Polycladida, Acotylea): new genus and combinations, European Journal of Taxonomy 264, pp. 1-30 : 12-14

Laqueusplana megala ( Marcus, 1952) comb. nov.

Figs 1 , 4 , 6B

Notoplana megala Marcus, 1952: 85 , figs 154–158.

Pleioplana megala – Faubel 1983: 117.

Examined material

One mature, sagittally sectioned specimen from the invertebrate collection of the Swedish Museum of Natural History in Stockholm ( Sweden), Cat Nr: SMNH 109094 to 109096 (3 slides).

Type locality

BRAZIL: Island of São Sebastião.

Description

Body shape elongated. Cryptic colour. Opaque dorsal appearance. Longitudinal median line not outstanding. Without mottled background. Smooth dorsal surface. Nuchal tentacles absent. Tentacular knobs present ( Fig. 1D ). Marginal eyes absent. Tentacles absent; instead tentacular eyes present in rounded and compact clusters. Dorsal and ventral frontal eyes absent. Cerebral eyes in two clusters ( Fig. 1E ). Pharynx located in second or last body third, strongly ruffled and ventrally oriented. Oral

pore position in second body third and in posterior region of pharynx. Intestine with numerous branches without anastomosis. Intestinal vesicles absent. Gonopores clearly separated.

MALE REPRODUCTIVE SYSTEM ( Fig. 4 A–E). Single male pore. Male copulatory apparatus not enclosed within muscular bulb, oriented forward and located in last body third. Ejaculatory duct with spiralshaped stylet (forming a loop between prostatic vesicle and pharynx). Prostatic vesicle interpolated. Connection between ejaculatory duct and prostatic vesicle with projection. Internal glandular lining of prostatic vesicle with tubular chambers. Extravesicular prostatic secretion. Prostatic glands located at proximal end of prostatic vesicle. Seminal vesicle simple or spindle-like. Spermiducal bulbs present.

FEMALE REPRODUCTIVE SYSTEM ( Fig. 4 A–D). Vagina elongated, tube-like, looping towards male complex. Bulbous Lang’s vesicle. Paired uterus. Uterine vesicles absent. Tube-like cement chamber. Endolecithal eggs.

Biology

Specimens found on algae from the upper littoral zone.

Distribution

Ilha de São Sebastião, Ubatuba (São Paulo State), Brazil.

Figures

Fig. 1. Species of Laqueusplana gen. nov. A. Dorsal view of a fixed specimen of Laqueusplana bocki gen. et sp. nov. B–C. Dorsal views of living specimens of L. bocki gen. et sp. nov. D. Dorsal view of a fixed specimen of L. megala (Marcus, 1952) comb. nov. E. Higher magnification view showing the eye arrangement of L. megala comb. nov.

Fig. 4. Laqueusplana megala (Marcus, 1952) comb. nov. A–B. Histological sections of the female reproductive system (anterior end to the left). C. Sagittal reconstruction of the reproductive system. D–E. Histological sections of the male reproductive system (anterior end to the left).

Fig. 6. Schematic representations comparing the copulatory apparatus. A. Laqueusplana bocki gen. et sp. nov. B. L. megala (Marcus, 1952) comb. nov. C. Melloplana ferruginea (Schmarda, 1859). D. M. japonica (Kato, 1937).