Transversotrema licinum Manter, 1970

Hunter, Janet A. & Cribb, Thomas H., 2012, A cryptic complex of species related to Transversotrema licinum Manter, 1970 from fishes of the Indo-West Pacific, including descriptions of ten new species of Transversotrema Witenberg, 1944 (Digenea: Transversotrematidae), Zootaxa 3176, pp. 1-44 : 17-19

Transversotrema licinum Manter, 1970 .

( Fig 3 )

Syn. Cribb et al. (1992) in part, not T. licinum of Grutter (1994), Hayward (1997) and Sey et al. (2003).

Type-host: “ Scorpius sp ( Scorpaenidae )” (true identity uncertain, but possibly Scorpis lineolata , Scorpididae ). Type-locality: Dunwich, Stradbroke I., Moreton Bay, Queensland

Other original hosts: (original, plausible): Microcanthus strigatus (Kyphosidae) .

Other hosts: (this study): Sparidae , Acanthopagrus australis (Günther) , Surf bream; Mugilidae , Liza argentea (Quoy & Gaimard) Flat-tail mullet; Paramugil georgii (Ogilby) , Silver mullet; Lutjanidae , Lutjanus fulviflamma (Forsskål) Dory snapper; Kyphosidae , Microcanthus strigatus (Cuvier) Stripey ; Scorpis lineolata Kner Silver Sweep ; Monodactylidae , Monodactylus argenteus (Linnaeus) Silver Mooney ; Pomacentridae , Abudefduf bengalensis (Bloch) Bengal Sergeant.

Site: Beneath scales

Material examined: see Table 3

Molecular sequence data: ITS2 rDNA

GenBank accession numbers: see Table 2

Deposited specimens: Holotype QM G231880 (ex M. argenteus MB coll. Hunter 14 Jan 2005) and paratypes QM G231881 (ex M. argenteus MB coll. Hunter 15 Jan 2005), QM G231882 (ex S. lineolata MB coll. Anderson & Cribb 27 Jan 1994), QM G231883 (ex S. lineolata MB coll. Anderson & Cribb 27 Jan 1994), QM G231884 (ex S. lineolata MB coll. Anderson & Cribb 27 Jan 1994), QM G231885 (ex M. argenteus MB coll. Hunter 14 Jan 2005), QM G231898 (ex M. argenteus MB coll. Hunter 14 Jan 2005) QM G231899 (ex A. bengalensis MB coll. Cribb Bray & Anderson 27 Jan 1994).

Description: Based on measurements of 6 specimens from kyphosids and monodactylids from Moreton Bay, Queensland. Body transversely elongated, strongly dorsoventrally flattened, 450–695 (475) long, 743–2,195 (1,504) wide; average width/length range 3:1. Pharynx to anterior margin 73–84 (79); cyclocoel to posterior margin at midline 134–153 (130). Tegumental spines prominent. Eyespots prominent, 67–240 (141) and 8.1% of body width apart; no pigment evident other than in eyespots. Ventral sucker well posterior to eyespots 2,648–6,884 (4,301) μm2. Mouth mid-ventral, inconspicuous. Pharynx between and posterior to eyespots, 40–114 (76) long, 35– 125 (70) wide. Oesophagus curved 36–111 (67). Caecal bifurcation dorsal to ventral sucker. Caeca form cyclocoel reaching laterally to envelop testes, ovary and some vitelline follicles. Testes opposite, deeply lobed, left 3,598– 47,626 (23,347) μm2; right 2,689–49,341 (23,970) μm2. Seminal vesicle formed of lobed, saccular enclosed portion and winding, tubular extracaecal portion. Enclosed portion distinctly lobed or entire, antero-dextral to right of testis, constricts distally to form narrow duct that passes ventral to cyclocoel to join tubular portion. Tubular portion of seminal vesicle passes mediad along cyclocoel then turns anteriorly and passes between eyespots dextral to pharynx, loops and passes to common genital pore where it unites with uterus without any specialisation. Common genital pore precisely in midline on anterior margin of worm. Ovary sinistral to left testis, with five prominent extended lobes, 1,155–16,454 (7966) μm2. Oviduct passes medio-posteriorly, unites with Laurer’s canal and duct from oviduct passes vitelline reservoir. Laurer’s canal then passes posteriorly to open dorsally close to left testis; median portion dilated, contains sperm or vitelline remnants. Vitelline reservoir immediately anterior to left testis. Extracaecal vitelline follicles small, confluent to lateral margins and posterior to cyclocoel, three or four follicles scattered along anterior margin of cyclocoel; posterior follicles number two or three between cyclocoel and posterior margin. Enclosed follicles in two loosely assembled masses at each lateral extremity, 20–42 (28); few follicles posterior to right testes along inner margins of cyclocoel. Uterus passes medially between anterior half of cyclocoel and testes then between right testis and saccular portion of seminal vesicle. Proximal portions of uterus act as seminal receptacle. Eggs 86–124 (101) long and, 36–50 (44) wide; number in utero 2–28 (14) (specimens from Microcanthus strigatus had many more eggs than Monodactylus argenteus specimens). Excretory bladder opens posteriorly at small notch in middle of posterior margin, extends anteriorly initially as narrow tube which then expands into large sac which passes ventral to cyclocoel anterior to which it becomes laterally directed.

Remarks: This species was described by Manter (1970) from two unrelated fishes from Moreton Bay, Queensland; however the type-host remains apparently unidentified (see Cribb et al. 1992 p. 916). T. licinum was reported by Cribb et al. (1992) from, inter alia, eight specimens from Lutjanus carponotatus , four L. adetii , four L. bohar , two L. quinquelineatus , one C. mertensii and two S. mongramma from Heron Island, and also from five Upeneus tragula Mullidae from Deception Bay, Queensland and from mugilid fishes–13 Mugil georgii , five Liza vaigensis , three Liza subviridis and two Valamugil cunnesius from waters off Gladstone, Queensland. Specimens were deposited in the Queensland Museum as T. licinum ; however, from the results from this study, and examination of the morphological samples we conclude that none of the specimens from these fishes are T. licinum sensu stricto, as specimens from the four lutjanids, the chaetodontid and the nemipterid are consistent with new species described here and will have new species names attributed to them. Molecular data from new specimens from Upeneus tragula from Moreton Bay revealed that they are part of the complex of species associated with mullid fishes and will be described with that complex. The specimens from the Mugilidae are more challenging to define. Transversotrema licinum was found from two mugilid species, Liza argentea and Paramugil georgii , from Moreton Bay in this study and sequences from the ITS2 rDNA confirm that they are identical to other specimens of T. licinum from that location reported in this study. There is no molecular material available of the specimens from the four mugilid species mentioned in Cribb et al. (1992) and as the fish from which they were retrieved are estuarine species and because no transversotrematids identical with T. licinum have been found anywhere but in Moreton Bay, we think it highly unlikely that they belong to that species. Following examination of the specimens at the Queensland Museum we found that these mugilid specimens are morphologically similar to species present at Heron Island which is in the same geographical region, yet despite examination of many mugilid fishes at Heron Island (>50) none has had an infection of T. licinum . Therefore, it is probable that they are a separate species, but until molecular data can be analysed their status remains indeterminate. Transversotrematidae were reported as T. licinum by Roubal (1998) from A. australis from Moreton Bay and this is consistent with our molecular data which places specimens from these sparids amongst a group with identical sequences and which we think are the “true” T. licinum . Grutter (1994) found transversotrematids, reported as T. licinum , from reef fishes from Lizard Island and Hayward (1997) reported T. licinum from sillaginid fishes from northern Australian waters. However, we regard these reports as highly unlikely as no T. licinum specimens (based on molecular data) have been found outside of Moreton Bay, which is off the SE coast of Queensland and has warm temperate waters as opposed to the tropical waters of the north. Hayward deposited transversotrematid specimens from sillaginid species from estuarine waters near Gladstone, in the Queensland museum. On inspection of these specimens, which are named as T. licinum , we found that they are morphologically distinct from the species described by Manter (1970) but will not be described until further data becomes available. Sey (2003) described T. licinum from sparid fish from the Red Sea; however, from his description we think this to be a separate species. Hunter et al. (2010) discuss reasons for not attributing three new species from Australian waters to T. haasi ( Witenberg 1944) also from the Red Sea, and until specimens from that locality become available for molecular and morphological examination we prefer to attribute T. licinum only to those specimens from Moreton Bay. From morphological and molecular data in this study, we now propose a different species (described below) for worms from L. carponotatus from Heron Island and other fishes mentioned in Cribb et al. (1992).

Two transversotrematid species were found in Moreton Bay, Queensland, the type locality for T. licinum . One is from two species of sillaginids (whiting) only and the other from six fish families—Kyphosidae, Lutjanidae , Monodactylidae , Mugilidae , Pomacentridae and Sparidae . One, Microcanthus strigatus , was the second fish from which T. licinum was identified by Manter (1970). Only molecular data were obtained for the first species from species of Sillaginidae ; however as there were no specimens suitable for morphological examination, this species was not described. For the second species, identical sequences were recorded from mugilids, lutjanines, monodactylids and sparids (with single bp differences for single sequences from Acanthopagrus australis and Monodactylus argenteus ). We conclude from these data that this second species is the true Transversotrema licinum as described by Manter (1970). Worms from Sillago ciliatus and S. analis have ITS2 sequences differing by 9 bp (2.6%) from that of T. licinum sensu stricto; this species remains unnamed until its morphology can be characterized.

Figures

FIGURE 3. Transversotrema licinum ex Monodactylus argenteus Moreton Bay. Scale = 200 μm.