Lurymare clavocapitata, Marquina, Daniel, Aguado, M. Teresa & Noreña, Carolina, 2015

Marquina, Daniel, Aguado, M. Teresa & Noreña, Carolina, 2015, New records of Cotylea (Polycladida, Platyhelminthes) from Lizard Island, Great Barrier Reef, Australia, with remarks on the distribution of the Pseudoceros Lang, 1884 and Pseudobiceros Faubel, 1984 species of the Indo-Pacific Marine Region, Zootaxa 4019 (1), pp. 354-377 : 369-370

Lurymare clavocapitata n. sp.

( Fig. 11 )

Material examined. Holotype: AM W.44692, MI QLD 2395. Paratype: AM W.44065, MI QLD 2351.

Diagnosis. The Lurymare species that has orange and blue-white dots on the dorsal surface. There are three dark brown stripes, one transversal in front of the cerebral eyes, two interrupted longitudinal at both sides of the pharynx; sometimes a white transversal stripe runs behind the cerebral eyes. The whole male copulatory apparatus is enclosed in a muscle bulb. Sucker is very close to the female pore.

Description. Elongated body is anteriorly rounded and pointed posteriorly, 9–12 mm long and 2–3 mm wide. Tentacles are absent. Cerebral eyes are in two close clusters of 10–12 eyespots each, with an anterior row of four eyes (two in front of each cerebral cluster), marginal eyes are in the anterior margin; there is a pair of ventral eyes in front of the brain. Dorsal surface is smooth. Dorsal colour pattern is transparent white with orange and bluewhite dots; a dark brown transversal stripe appears at the front of the cerebral eyes, and a white one behind them. There are two intermittent dark brown stripes at both sides of the median line ( Fig. 11 A) that do not reach the posterior end. Pharynx is plicate tubular, occupies one third of body length. Oral pore is behind brain. Male and female pores are close to each other at the middle of the body. Sucker is very close to female pore. Male reproductive system consists of a large, spherical and heavily muscularised seminal vesicle, two spherical prostatic vesicles, and an armed penis papilla, all enclosed together with the male atrium in a muscular bulb. Spermiducal vesicles are present. Ejaculatory duct is wide with a thick muscular layer. Prostatic vesicles are spherical. Prostatic ducts are narrow, with a muscular layer. Prostatic ducts run attached to the ejaculatory duct, but without any tissue bounding them. Penis papilla is armed with a slender stylet. Atrium is deep ciliated ( Fig. 11 B–F). Female system lies immediately posterior to male muscular bulb. Proximal end of vagina is bended forward, descends straight to cement pouch and opens in a heart-shaped female atrium. Cement glands are well developed ( Fig. 11 C, E, F).

Remarks. The enclosing of the three vesicles (two prostatic vesicles and the seminal vesicle) into a common muscle bulb places the examined specimens into the genus Lurymare Marcus & Marcus, 1968 , together with L. drygalskiii ( Bock, 1931) , L. katoi ( Poulter, 1975) , L. monosorum ( Schmarda, 1859) , L. singulare ( Laidlaw, 1904) , and L. utarum ( Marcus, 1952) ( Faubel 1984; Bahia et al. 2014). Among them, L. utarum and L. drygalskii are found in the Atlantic Ocean ( Bock 1931; Marcus 1952; Quiroga et al. 2004a; Bahia et al. 2014), while L. katoi , L. monosorum and L. singulare present an Indo-Pacific distribution. Lurymare clavocapitata n. sp. can be easily distinguished from L. singulare , L. utarum and L. monosorum by their dorsal colouration, which is white cream to ivory, with a brown median line, and dark-reddish brown central line. Bock (1931) did not mention the colouration of L. drygalskii , but this species can be distinguished from L. clavocapitata n. sp. in the reproductive anatomy: both the penis papilla and the sucker are much larger in L. drygalskii than in L. clavocapitata n. sp., while the male atrium is narrower and deeper in L. clavocapitata n. sp. Furthermore, the characteristic three brown stripes present in L. clavocapitata n. sp. did not disappear after fixation and they are not present in Bock’s drawings ( Bock 1931, Taf. 45, Fig. 18).

L. clavocapitata n. sp. shows some similarities in the dorsal colouration with L. katoi , as the white colour with orange-gold spherules. However, L. katoi lacks the blue-white dots and the three (one transversal, two longitudinal) brown stripes characteristic of L. clavocapitata n. sp. In respect of the internal anatomy, the male atrium is deeper in L. clavocapitata n. sp., and is included in the common muscular bulb, the feature that does not appear in L. katoi . Also, the sucker is much closer to the female pore in L. clavocapitata n. sp. than in L. katoi .

In the paratype, which is smaller than the holotype, although is a mature specimen, the white transversal stripe behind the cerebral eyes is absent. However, a similar colour variation has been reported for Prosthiostomum trilineatum Yeri & Kaburaki, 1920 by Newman & Cannon (2003) and Pitale et al. (2014).

Etymology. The specific name derives from the Latin clavo (=line) + capita (=head), for the distinctive transversal brown stripe before the eyes.

Habitat. Holotype found on rocks over fine sand, while the paratype was found on coral rubble and flat algae.

Type locality. Coconut Beach, Lizard Island (Queensland, Australia), 14°40'53"S, 145°28'12"E.

Figures

FIGURE 11. Lurymare clavocapitata n. sp., AM W. 44065, MI QLD 2351, AM W. 44692, MI QLD 2395. A. Live specimen; B – E. Histological sections of the reproductive system; F. Sagittal reconstruction of the reproductive system, anterior to the left in B – F. Abbreviations: cg = cement glands, fa = female atrium, i = intestine, ma = male atrium, pv = prostatic vesicle, s = stylet, spv = spermiducal vesicles, su = sucker, sv = seminal vesicle.