Haemaphysalis (Rhipistoma) dentipalpis Warburton & Nuttall, 1909 (Acari: Ixodidae) is reinstated here as a valid species and the male is redescribed whereas the female is described for the first time. The adults of H. dentipalpis that we studied were collected from various felid and viverrid carnivorans (Carnivora: Felidae, Viverridae) in Indonesia and Malaysia. For comparative purposes, the male and female of H. (R.) asiatica (Supino, 1897) are redescribed. The adults of H. asiatica that we studied were from various felid and viverrid carnivorans (Carnivora: Felidae, Viverridae) as well as a treeshrew (Scandentia: Tupaiidae) in Thailand and Vietnam. The males and females of both H. dentipalpis and H. asiatica can be differentiated by the pattern of punctations on the conscutum and scutum and the shape and size of the posterodorsal and posteroventral spurs on palpal segment II.
Questing is a situation when a tick is seeking to get closer or ambush its potential host. However, information on questing tick species in Malaysia is still lacking, thus the association with tick-borne diseases (TBD) is not completely understood. The aim of this study was to investigate the tick species from five most frequently visited recreational areas in Pahang and Terengganu states, which were recorded to have high potential of TBD cases. By implementing handpick method, a total of 18 males and 15 females belonging to five Dermacentor Koch, 1844 species, were collected, namely D. compactus Neumann 1901, D. tricuspis (Schulze, 1933), D. auratus Supino 1897, D. steini (Schulze, 1933), and D. falsosteini Apanaskevich, Apanaskevich & Nooma respectively. The specimens were collected and identified based on morphological characters prior to obtaining the molecular data of COI and 16S rDNA. The D. compactus was the most abundant species collected in this study, while D. falsosteini was the least. All species were distinctly separated on the Neighbor Joining and Maximum Parsimony tree topologies and supported with high bootstrap values. Furthermore, a low intraspecific variation (0.00 - 0.01) was observed amongst the individuals of the same species in both genes. Meanwhile, each Dermacentor species was genetically different, with interspecific values ranging from 0.13-0.19 and 0.11-0.20 for COI and 16S rDNA. These findings had successfully recorded the tick species that were potentially associated with TBD, and which might be circulated among humans and animals. This study also has some implications on the diversity and geographical extension of Dermacentor ticks, thus should warrant further investigation as a potential vector of tick-borne diseases and public health importance.
Re-examination of the holotype of Dermacentor atrosignatus Neumann, 1906 (Acari: Ixodidae) stored in the Natural History Museum (London, UK) revealed that this taxon is identical with D. auratus Supino, 1897 and should be treated as a junior synonym of the latter species. A correct name for the distinct species previously identified as D. atrosignatus Neumann, 1906 sensu Wassef & Hoogstraal, 1984 should be D. tricuspis (Schulze, 1933) n. comb., n. stat. Adults of D. tricuspis are redescribed here. Re-examination of extensive holdings of Oriental Dermacentor Koch, 1844 ticks stored in the United States National Tick Collection revealed that a morphologically distinct new species of this genus, namely D. falsosteini D. Apanaskevich, M. Apanaskevich & Nooma n. sp. should be recognized. Adults of D. tricuspis and D. falsosteini n. sp. can be distinguished from other species of Oriental Dermacentor and each other by the colour pattern of the conscutum and scutum, the pattern of punctations on the pseudoscutum and scutum, the shape of female genital structures and spurs on coxa I. Dermacentor tricuspis is recorded from Indonesia, Malaysia, the Philippines and Thailand where the adults were mostly collected from various species of wild pigs (Artiodactyla: Suidae) and vegetation; few adults were available from other mammals (Artiodactyla: Bovidae; Carnivora: Canidae, Felidae, Ursidae; Pholidota: Manidae), as well as humans and reptiles (Squamata: Elapidae, Varanidae). One male was reared from a nymph collected on a rodent (Rodentia: Muridae). Dermacentor falsosteini n. sp. is found in Indonesia, Malaysia and Thailand where the adults were collected from bearded pig, Sus barbatus Müller, wild boar, S. scrofa Linnaeus, unidentified wild pig, Sus sp. (Artiodactyla: Suidae), Malayan tapir, Tapirus indicus Desmarest (Perissodactyla: Tapiridae), human and vegetation.
A new species of Acroeimeria Paperna & Landsberg, 1989 is described from the spotted house gecko, Gekko monarchus (Schlegel) from Peninsular Malaysia. Oöcysts of Acroeimeria grismeri n. sp. are spheroidal to subspheroidal with a smooth bi-layered wall, measure on average 18.4 × 17.3 µm, and have a length/width (L/W) ratio of 1.1; a micropyle and an oöcyst residuum are absent but variable polar granule(s) are present, commonly in Brownian movement. Sporocysts are ellipsoidal and measure on average 8.6 × 6.7 µm, L/W 1.3; Stieda, sub-Stieda and para-Stieda bodies are absent. The sporocyst residuum is composed of numerous spheroidal granules in the center of the sporocyst. This is the initial species of coccidian reported from G. monarchus and one of the few reported from any reptile from Peninsular Malaysia.
Two new tentaculariid species were found infecting carcharhiniform sharks from off the coasts of Malaysian Borneo and the southwestern coast of the Baja California Sur, Mexico. Both new species exhibit a homeoacanthous heteromorphous basal and a homeoacanthous homeomorphous metabasal armature. Since this hook arrangement is unique within the tentaculariids and the taxonomy in this group deeply depends on the tentacular armature, Reimeriella n. g. is erected to accommodate R. varioacantha n. sp. ex Carcharhinus sorrah (Müller & Henle) and R. mexicoensis n. sp. ex Sphyrna lewini (Griffith & Smith). Unlike R. mexicoensis n. sp., R. varioacantha n. sp. has a pars bothrialis not overlapping the pars bulbosa and the number of testes is higher. Reimeriella mexicoensis n. sp. possesses very large uncinate to falcate hooks in the basal armature, while in R. varioacantha n. sp. these hooks are almost the same in size as the remaining hooks in both the basal and metabasal armature. The latter species is the first tentaculariid species where the metabasal armature very closely resembles an eutetrarhynchid with a heteroacanthous typical homeomorphous metabasal armature and a high number of spiniform hooks per half spiral row (10-11 vs 6-7 in R. mexicoensis n. sp.) in the metabasal and apical armature. This pattern provides further morphological evidence for the close relationship of the Eutetrarhynchoidea and the Tentacularioidea. Reimeriella varioacantha n. sp. enriches the trypanorhynch fauna from off the coast of Malaysian Borneo while R. mexicoensis n. sp. is a novel record of a tentaculariid trypanorhynch from the Mexican Pacific.
Three species of Opisthomonorcheides Parukhin, 1966 are reported for the first time from Indonesian waters: O. pampi (Wang, 1982) Liu, Peng, Gao, Fu, Wu, Lu, Gao & Xiao, 2010 and O. ovacutus (Mamaev, 1970) Machida, 2011 from Parastromateus niger (Bloch), and O. decapteri Parukhin, 1966 from Atule mate (Cuvier). Both O. pampi and O. ovacutus can now be considered widespread in the Indo-Pacific region, with earlier records of these species being from Fujian Province, China and Penang, Malaysia, respectively. We redescribe O. decapteri from one of its original hosts, Atule mate, off New Caledonia, and report this species from Jakarta Bay, Indonesia, extending its range throughout the Indian Ocean into the south-western Pacific. All three species possess a genital atrium that is long, sometimes very long, and a genital pore that is located in the forebody. This validates the interpretation that the original description was erroneous in reporting the genital pore in the hindbody, well posterior to the ventral sucker. These observations verify the synonymy of Retractomonorchis Madhavi, 1977 with Opisthomonorcheides. A major discrepancy between the species of Opisthomonorcheides is that some are described with the uterus entering the terminal organ laterally and some with it entering terminally; this feature needs further analysis. Based on the length of the genital atrium and the posterior extent of the vitellarium, the 27 species of Opisthomonorcheides considered valid can be divided into four groups. Among the 53 host records analysed, the families Carangidae (53% of records), Stromateidae (17%) and Serranidae (5.7%) are the most common; the reports are overwhelmingly from members of the Perciformes (91%), with further records in the Clupeiformes (5.7%), Gadiformes (1.9%) and Pleuronectiformes (1.9%). Two fish genera (Parastromateus Bleeker and Pampus Bonaparte) dominate the recorded hosts, with the black pomfret Parastromateus niger harbouring six species, the silver pomfret Pampus argenteus (Euphrasen) harbouring six, and the Chinese silver pomfret P. chinensis (Euphrasen) two. A host-parasite checklist is presented. We discuss the host-specificity of members of the genus, questioning some records such as that of O. decapteri in a deep-sea macrourid. We also comment on the morphological similarity, but phylogenetic distance, between the various Pomfret species, advancing the possibility that a series of host misidentifications has occurred. Sequences of the ITS2 rDNA gene generated for O. pampi and O. ovacutus are briefly discussed and molecular data are lodged in the GenBank database.
Dermacentor tamokensis n. sp. and Dermacentor pseudocompactus n. sp. (Acari: Ixodidae) are described based on adults ex wild boar and vegetation from China, India, Malaysia, and Vietnam and males ex wild boar from Nepal, respectively. Adults of D. tamokensis n. sp. are similar to those of D. taiwanensis Sugimoto, 1935 and D. atrosignatus Neumann, 1906 but can be distinguished by the colour pattern of the conscutum and scutum, the size and density of punctations on the pseudoscutum and scutum, the width of the cornua, and the shape of female genital structures. Males of D. pseudocompactus n. sp. are most similar to those of D. compactus Neumann, 1901 but can be distinguished by the colour pattern, sculpture and punctations of the conscutum, and the shape and length of the coxal spurs.
Proyseria decora (Dujardin, 1845) (the type-species of the genus Proyseria Petter, 1959) is redescribed on the basis of specimens from Alcedo atthis (L.) (Coraciiformes: Alcedinidae) from Iran. P. petterae n. sp. is described from Corythornis vintsioides (Eydoux & Gervais) (Alcedinidae) from Madagascar by light and scanning electron microscopy. Proyseria sp. from Alcedo euryzona Temminck from continental Malaysia is described on the basis of a single male specimen. Stegophorus alcedonis Puqin, Yanyin & Guocal, 1991 from A. atthis in China is transferred to the genus Proyseria as P. alcedonis n. comb. The generic diagnosis of Proyseria is amended. Review of the species of the genera Proyseria and Stegophorus Wehr, 1934 is presented.
Molecular and morphometric investigations were conducted on the actinosporean morphotypes of myxosporeans surveyed in oligochaetes of Lake Balaton and Kis-Balaton Water reservoir. Oligochaetes belonging to the species Isochaetides michaelseni Lastočkin and Branchiura sowerbyi Beddard as well as to the genera Nais Dujardin, Dero Müller and Aeolosoma Ehrenberg were studied during an 18-month period. Actinosporeans were obtained exclusively from I. michaelseni (7,818 specimens) with very low prevalence (0.01-0.06%). Four new actinosporean morphotypes of the collective groups raabeia (2 types), synactinomyxon (1 type) and neoactinomyxum (1 type) were found and described, including the first synactinomyxon collective group from Hungarian biotopes and a new raabeia morphotype. Except for Synactinomyxon type 1, the 18S rDNA analysis revealed that the spores did not match any myxospore entity found in the GenBank.
Quazithelazia rostrata n. sp. from Ceyx erithaca (L.) (type-host) and Alcedo euryzona Temminck (Coraciiformes, Alcedinidae) and Q. alata n. sp. from Enicurus ruficapillus Temminck (Passeriformes, Muscicapidae) are described from vicinities of Gombak Biological Station, Selangor, Malaysia; both species are parasitic under the koilin lining of the gizzard. Paratypes of Schistogendra pelargopsis Nandi, De & Majumdar, 1985, a parasite of Pelargopsis capensis (L.) (Alcedinidae) from India, are redescribed and the species is recognised as a junior synonym of the type-species of Quasithelazia, Q. tenuis Maplestone, 1932 (new synonymy), a species originally described from Halcyon smyrnensis (L.) (Alcedinidae) in India. An amended diagnosis of the genus Quasithelazia Maplestone, 1932 is proposed. Currently, this genus includes eight species occurring in the Old World, six of them parasitic in kingfishers (Alcedinidae) and two species parasitic in flycatchers (Muscicapidae). These include, inter alia, Q. halcyoni n. comb. for Viktorocara halcyoni Ryzhikov & Khokhlova, 1964 from Halcyon smyrnensis and H. pileata (Boddaert) in Vietnam and the Russian Far East, Q. microcordonis n. comb. for Rusguniella microcordonis Schmidt & Kuntz, 1971 from Halcyon coromanda major (Temminck & Schlegel) in Taiwan and Q. multipapillata n. comb. for Schistogendra multipapillata Zhang, 1993 from Tarsiger cyanurus (Pallas) (Muscicapidae) in China. Comparative morphological data for Quasithelazia spp. are presented. Schistogendra oligopapillata Zhang & An, 2002 from domestic ducks in China is considered a species incertae sedis.
Culturing fishes in marine cages is a rapidly developing area of marine aquaculture. The Asian seabass Lates calcarifer (Bloch) is a fast growing good quality fish that is readily cultured in intensive systems in the South Asian region and in Malaysia in particular. Although several papers have been published to date on viral, bacterial, parasitic and fungal organisms causing diseases in the Asian seabass, the occurrence of a coccidian infection in this species has only recently been recorded. We collected sporulated and unsporulated oöcysts of a new species of Goussia Labbé, 1986, from the mucus covering the epithelium of the intestine of L. calcarifer. This paper provides a description of Goussia kuehae n. sp. Sporulated oöcysts of this species are ellipsoidal, 37-40 μm in length and 28-30 μm in width. The ellipsoidal sporocysts are relatively small, 15.2-17 × 5.7-8 μm, and located loosely in the oöcyst. There are residual bodies both in the oöcysts and the sporocysts. Goussia kuehae n. sp. differs from all known species of Goussia in the large size of the oöcysts and in having two types of oöcyst residuum.
Sampling of a large number of elasmobranchs from coastal waters off Borneo revealed the presence of five new species of Dollfusiella Campbell & Beveridge, 1994 (Trypanorhyncha: Eutetrarhynchidae), namely D. angustiformis n. sp., D. hemispinosa n. sp., D. spinosa n. sp., D. imparispinis n. sp. and D. parva n. sp. Dollfusiella angustiformis n. sp. is described from the spiral intestines of four species of the dasyatid stingray genus Himantura Müller & Henle from both the Indonesian and Malaysian parts of Borneo. All the other species were obtained from Malaysian Borneo. Dollfusiella hemispinosa n. sp. is described from the spiral intestines of three species of Himantura, whereas D. spinosa n. sp. was obtained from several specimens of Pastinachus solocirostris Last, Manjaji & Yearsley (Dasyatidae) as well as from Taeniura lymma 1 (sensu Naylor et al., 2012) (Dasyatidae), Neotrygon kuhlii 2 (sensu Naylor et al., 2012) (Dasyatidae), and Glaucostegus cf. typus (sensu Naylor et al., 2012) (Rhinobatidae). Dollfusiella imparispinis n. sp. is described from the spiral intestine of a single specimen of Chiloscyllium punctatum Müller & Henle (Hemiscyllidae) from the South China Sea off Sarawak, whereas D. parva n. sp. was obtained from several species of Himantura. Specimens of the five novel taxa possess scoleces covered with enlarged microtriches, a morphological characteristic exhibited by several other congeners. However, the new species differ from all congeners by possessing unique patterns of oncotaxy as well as combinations of additional morphological features. The number of valid species within Dollfusiella is increased to 26. For this reason, a key for the species of Dollfusiella is provided. Furthermore, novel information on hosts and geographic distribution is provided for two previously described species of Dollfusiella, D. michiae (Southwell, 1929) and D. spinulifera (Beveridge & Jones, 2000). The latter species differs slightly from the original description and shows a much higher variability with regard to the lengths of the scolex and muscular bulbs and the number of testes. These variable characters subdivided specimens of D. spinulifera into relatively distinct groups. However, the specimens did not differ in their oncotaxy and are considered to represent a single variable species.
Septesinus gibsoni n. g., n. sp. (Monocotylidae: Heterocotylinae) is described from the gills of the dwarf whipray Himantura walga (Müller & Henle) collected in marine waters off Sarawak (Borneo), Malaysia. Septesinus n. g. is distinguished from other genera in the Monocotylidae by a combination of characters, including a haptor with one central and seven peripheral loculi, the presence of a highly sinuous ridge surmounting all haptoral septa, four rounded accessory structures on the dorsal surface of the haptor, and the anterior region with two pairs of anteromedian and three pairs of anterolateral gland-duct openings. Septesinus n. g. is accommodated in the Heterocotylinae. Septesinus gibsoni n. sp. is described and fully illustrated, and a key to the genera of Heterocotylinae is provided. The composition of the ridges surrounding the mouth of a number of heterocotyline species and their usefulness as a taxonomic character are examined. The identity of four specimens of Monocotyle Taschenberg, 1878, also recovered from the gills of this host species, is discussed.
Three new species of Merizocotyle Cerfontaine, 1894 (Monogenea: Monocotylidae) are described from the nasal tissues of stingrays collected off Borneo. Merizocotyle macrostrobus n. sp. is described from the dwarf whipray Himantura walga (Müller & Henle) collected in shallow waters off Sematan, Sarawak, Malaysia. This species can be distinguished from the other members of the genus by the morphology of the sclerotised male copulatory organ, which is long with many twists and loops. The vaginae of this species are also long and looped. Merizocotyle papillae n. sp. is described from the roughnose stingray Pastinachus solocirostris Last, Manjaji & Yearsley collected off Sematan and Mukah, Sarawak, Malaysia. It is distinguished from the other species of Merizocotyle by the morphology of the male copulatory organ, which is a sclerotised tube that expands slightly and then tapers at the distal end, and by the presence of papillae on the dorsal edge of the haptor. Merizocotyle rhadinopeos n. sp. is described from the whitenose whip ray Himantura uarnacoides (Bleeker) collected off Manggar, East Kalimantan, Indonesia. It can be differentiated by the male copulatory organ, which is a short, narrow, curved, sclerotised tube tapering distally, and the path of the ovary, which runs anteriorly to the base of the oötype. We also provide details of new host and/or locality records for M. australensis (Beverley-Burton & Williams, 1989) Chisholm, Wheeler & Beverley-Burton, 1995, M. icopae Beverley-Burton & Williams, 1989 and M. pseudodasybatis (Hargis, 1955) Chisholm, Wheeler & Beverley-Burton, 1995.
A new genus of trypanorhynch cestode is described from two species of sharks, the sliteye shark Loxodon macrorhinus Müller & Henle and the straight-tooth weasel shark Paragaleus tengi (Chen) collected in the Makassar Strait (off Indonesian Borneo) and Sulu Sea (off Malaysian Borneo). Ancipirhynchus afossalis n. g., n. sp. possesses two bothria and a heteroacanthous, heteromorphous tentacular armature with three distinctive files of hooks on the external tentacle surface but lacks prebulbar organs and gland cells within the tentacular bulbs. The hook arrangement of alternating files on the external surface of the tentacle resembles that seen in the superfamily Otobothrioidea Dollfus, 1942 in the genus Fossobothrium Beveridge & Campbell, 2005. However, the new species lacks the defining characteristic of this group, i.e. the paired bothrial pits. A Bayesian inference (BI) analysis of 37 LSU sequences of trypanorhynchs from three superfamilies provided evidence supporting the taxonomic placement of Ancipirhynchus afossalis n. g., n. sp. within the Otobothrioidea.
Lethrinitrema gibbus n. g., n. sp. and L. dossenus n. sp. are described from the fish Lethrinus rubrioperculatus Sato collected off New Caledonia, South Pacific. Members of Lethrinitrema n. g. (Ancyrocephalidae) are characterised by having two pyriform haptoral reservoirs and ventral anchors with lateral grooves. The elongate tubular distal end of each reservoir bifurcates, draining into a superficial lateral groove on each side of the ventral anchors. The haptoral reservoirs are postulated to store secretory products which assist in attachment to the host. Lethrinitrema spp. also possess tandem gonads, a male copulatory organ without an accessory piece or with thinly sclerotised accessory piece, and a dextrolateral, non-sclerotised vaginal bulb. The two new species have small, poorly demarcated haptors with small haptoral armament and a crown-like piece on the tip of the inner root of the ventral anchors. They differ from each other in the shape and size of the ventral bar and male copulatory organ (40-45 μm in length in L. gibbus vs 24-30 μm in L. dossenus). Three other species, previously included in Haliotrema Johnston & Tiegs, 1922, are transferred to Lethrinitrema, i.e. L. chrysostomi (Young, 1968) n. comb., L. fleti (Young, 1968) n. comb. (both briefly redescribed from paratypes) and L. lethrini (Yamaguti, 1937) n. comb. All species of Lethrinitrema parasitise Lethrinus spp. (Lethrinidae), and there is evidence for the existence of further Lethrinitrema spp. on Lethrinus spp. in the Indo-Pacific region.
Four new and one unidentified species of Neohaliotrema Yamaguti, 1965 were obtained from the gills of the Indo-Pacific sergeant Abudefduf vaigensis (Quoy & Gaimard) off Pulau Langkawi, Malaysia. The five species, N. malayense n. sp., N. bombini n. sp., N. andamanense n. sp., N. parvum n. sp. and an unidentified Neohaliotrema sp. (similar to N. macracanthum Zhukov, 1976), are described and distinguished based mainly on features of the haptor. Species of this genus are divisible into two groups, the 'maomao group', with two pairs of morphometrically modified 'marginal' hooks and a fenestrated haptor, and the 'gracile group', with morphologically similar marginal hooks and an entire haptor. With the exception of N. bombini n. sp., the species described fit within the 'maomao group'. It is suggested that the more complex Neohaliotrema species of the 'maomao group' have modified hooks 1 and 2 on a haptoral 'isthmus' between two large apertures, i.e. 'windows', whereas the less complex species lacking these features are those of the 'gracile group'. Neohaliotrema spp. have only a single pair of pigmented eye-spots. A fenestrated haptor is unique to the Neohaliotrema spp. of the 'maomao group'. The generic diagnosis of Neohaliotrema is amended to include new data and a key to its known species is presented.
Monogeneans identified as Sinodiplectanotrema malayanum n. sp. were collected from the fish Pennahia anea (Sciaenidae) off the west coast of Peninsular Malaysia. The new species is recognised on the basis of morphometrical differences in the anchors, marginal hooks and eggs and apparent differences in the 28S rDNA sequence data. The new species possesses features (ovary looping the intestinal caecum, body spines, a vagina and haptoral reservoirs) not noted in the original description of the type and only other species of the genus, S. argyrosomus Zhang, 2001, necessitating the re-assignment of the genus to the Diplectanidae Monticelli, 1903, a move which is supported by 28S rDNA evidence. Sinodiplectanotrema is redefined on the basis of the observation of several features not included in the original diagnosis.
Sundatrema langkawiense n. g., n. sp. (Monogenea: Ancyrocephalidae) is described from the gills of the orbfish Ephippus orbis (Bloch) (Ephippidae) off the Island of Langkawi, Malaysia, in the Andaman Sea. This new genus has the ancyrocephalid characteristics of four anchors, 14 marginal hooks and two bars, but differs from other four-anchored monogenean genera, and notably from Parancylodiscoides Caballero & Bravo Hollis, 1961 (found on the ephippids Chaetodipterus spp. off Central and South America), by having a unique combination of features. These include a muscular genital sucker and a vas deferens and vagina on the same (sinistral) side of the body. It is similar to Parancylodiscoides in having four haptoral reservoirs opening at the anchoral apertures, four anchors, similar connecting bars and small marginal hooks. The new species is characterised by the above generic features and by possessing a small, short copulatory organ lacking an accessory piece. Diplectanum longiphallus MacCallum, 1915 (previously attributed to Ancyrocephalus Creplin, 1839, Tetrancistrum Goto & Kikuchi, 1917 and Pseudohaliotrema Yamaguti, 1953) is transferred to Parancylodiscoides as P. longiphallus (MacCallum, 1915) n. comb.
One new and four previously described species of Triacanthinella Bychowsky & Nagibina, 1968 (Monogenea) were collected from the tripodfishes Triacanthus biaculeatus and Tripodichthys blochii off Peninsular Malaysia. Triacanthinella lumutensis n. sp. from Tripodichthys blochii off Lumut, Selangor is similar to Triacanthinella principalis Bychowsky & Nagibina, 1968 in having morphologically similar types of haptoral sclerites and copulatory organ, but differs in possessing a longer copulatory tube. Also re-described are T. principalis Bychowsky & Nagibina, 1968, T. gracilis Bychowsky & Nagibina, 1968 and T. aspera Bychowsky & Nagibina, 1968 from both Triacanthus biaculeatus and Tripodichthys blochii, plus Triacanthinella longipenis Bychowsky & Nagibina, 1968 from Tripodichthys blochii and Triacanthinella tripathii Bychowsky & Nagibina, 1968 based on its type-material. In the new species, the filament loop of the anchors is associated with a sheath-like sclerite which envelops the anchor point. Such sclerites were also observed in the present specimens of Triacanthinella principalis, T. aspera, T. longipenis and T. gracilis but were not mentioned in the original descriptions. The generic diagnosis of Triacanthinella is amended and a key to the recognised species is presented. The specific names of two of the previously described species are emended from the neuter form to T. principalis and T. gracilis.