Predorsal Length Research Articles

Schistura sonarengaensis, a new species of cave-dwelling loach (Teleostei: Nemacheilidae) from Meghalaya, northeast India.

A new species of nemacheilid loach, Schistura sonarengaensis sp. nov., is described from three cave-dwelling populations (Barak-Surma-Meghna drainage) in the South Garo Hills district of Meghalaya, India. The new species possesses prominent eyes but is easily distinguished from all the congeners of the genus Schistura from Barak-Surma-Meghna and adjacent rivers drainages of northeast Indian (except S. syngkai) in having 13-26 vertically elongated to circular mid-lateral black blotches (brownish in life) overlayered on a grayish-black mid-lateral stripe on a dull white or pale-beige (golden brown in life) body. However, it can be easily distinguished from S. syngkai in having a complete (vs. incomplete) lateral line with more 72-89 (vs. 19-42) lateral-line pored scales, greater pre-dorsal length (48.5-53.1 vs. 41.9-44.1 %SL), a wider body at dorsal-fin origin (11.3-16.7 vs. 9.4-10.3 %SL), greater dorsal (18.1-21.1 vs. 15.1-17.0 %SL) and lateral (20.9-24.1 vs. 17.4-18.9 %SL) head length, a wider head (14.5-18.5 vs. 11.6-13.3 %SL), and moderately forked (vs. emarginated) caudal fin. Further, molecular analysis confirms the distinctiveness of S. sonarengaensis sp. nov. from its congeners found in northeast India by significant divergences with uncorrected genetic distance ranging from 3.7% to 17.3% in the mitochondrial cytochrome c oxidase subunit I (COI) gene dataset. The phylogenetic position of the new species with its sister species was evaluated using maximum likelihood and Bayesian analysis. The species delimitation approaches assemble species by automatic partitioning (ASAP) and Poisson tree processes (PTP) utilized for testing species assignments consistently identified our test group as a distinct species from its sister species. Although the new species lacks typical morphological adaptations usually associated with a subterranean life, such as complete absence (or vestigial presence) of eyes and pigmentation, it exhibits a reduction of pigmentation when compared to the epigean congeners.

Sexual dimorphism and species divergence between a habitat generalist and a habitat specialist

AbstractSexual dimorphism, the phenotypic differences between males and females within a species, is widespread in the animal kingdom. This study investigates the extent of sexual dimorphism and species divergence in external morphology in two closely related freshwater fish species, Devario malabaricus and D. micronema, in Sri Lanka. Devario malabaricus, a habitat generalist, inhabits a wide range of aquatic environments, while D. micronema, a habitat specialist, resides in shaded rainforest streams. The study reveals size differences between the two species: D. malabaricus is consistently larger than D. micronema. However, there are no size differences between the sexes within each species. Several additional morphological traits, such as head length, interorbital width, predorsal length and postdorsal length display divergence between the species as well as between the sexes within each species; these patterns are also consistent across populations. The sexually dimorphic traits are similar between the two species despite their distinct ecological habitats. However, Devario malabaricus exhibit stronger sexual dimorphism compared to D. micronema, supporting the prediction of a positive relationship between the extent of sexual dimorphism and ecological generalism. The study highlights the importance of considering sexual dimorphism in morphometric comparisons in taxonomic studies of Devario and suggests that divergent selection between the sexes contributes to morphological variation in this group.

INTRA-SPECIFIC DIVERSITY OF THE SILVER GRUNT (Pomadasys Hasta) IN THREE LOCATIONS OF BANGLADESH BASED ON MORPHOMETRIC ANALYSIS

Morphometric variation is a useful tool for studying a species' population structure. The present study was performed to assess the intra-specific diversity between three stocks of the Silver grunt Pomadasys hasta (Khulna, Satkhira and Patuakhali of Bangladesh). Length-weight relationship, condition factor and few other morphometrics were analyzed using both univariate and multivariate approaches. A total of 105 samples were subjected to the analysis (weight (95.05 ±44.22 g) and length (16.18±2.57cm). A total of eleven morphometric traits including standard length (SL), head length (HL), pre dorsal length (Pre DL), dorsal length (DL), pre-anal length (Pre AL) , pre-pelvic length (PreVL) , pre pectoral length (PrePL), pre-orbital length (PrOL), body depth (BD), eye diameter (ED) and pre orbital length (PreOL) were measured. Significant differences were found in four morphometric measurements including head length (HL % of total length), eye diameter (ED % of HL), dorsal length (DL %) and pre dorsal length (PreDL%). A negative allometric growth was observed, as the slope b was far below 3. The highest value of b was found in Satkhira (2.7) and the lowest value of b was found in Khulna (2.07). Three separate stocks of P. hasta exhibited morphological variations in their attributes. The divergence among the stocks could have resulted from both environmental and genetic variances. The outcomes of the study will be helpful for management and conservation of natural population of Datina (P. hasta) in Bangladesh.

Evaluation of body performance of tilapia (Oreochromis niloticus)

Efforts to improve the quality of fish seeds can be done by using quality broodstock which includes having the right body shape. This study aimed to evaluate the body performance of male and female Sultana strain tilapia (Oreochromis niloticus) which were to be used in hatchery activities. A total of 35 male and 35 female broodstock were evaluated for body size using a ruler. Measurements of 12 morphological characters: total length (TL), standard length (SL), head length (HL), pre-dorsal length (PrDL), pre-pectoral length (PrPL), pre-pelvic length (PrPeL), pre-pelvic length (PrPeL), anal length (PrAL), anal fin length (AFL), dorsal fin base length (DFL), body height (BH), caudal peduncle height (CPH), and dorsal anal length distance (DAL). The ratio between the character values of SL, HL, PrDL, PrPL, PrPeL, PrAL, AFL, DFL, BH, CPH, DAL, and TL were analyzed descriptively. The results of the analysis showed that the average value of the ratio of length characters (SL/TL, HL/TL, DF, and AFL/TL), height character (BH/TL), and diagonal character (DAL/TL) were higher in the male broodstock than in the female broodstock. On the other hand, other length characters (PrDL/TL, PrPL/TL, PrPeL/TL, PrAL/TL) and height characters (CPH/TL) had the same values in the male and female broodstock. In general, the size of the male broodstock used tended to be larger than the female broodstock.

HABITUS COMPARASION, GROWTH PATTERN AND CONDITION OF CONVICT CICHLID (Amatitlania nigrofasciata GUNTHER, 1986) IN THREE LAKES ECOSYSTEMS IN BALI

Convict cichlid (Amatitlania nigrofasciata) belonging to the Cichilidae family has inhabited in Tamblingan Lake, Buyan Lake and Beratan Lake. The existence of this fish species is suspected due to accidental introduction activities. The aims of this study ware to reveal differences in habitus, growth patterns and conditions of convict cichlid in the three lakes on the island of Bali. Samples of convict cichlid were taken by bubu traps, that placed in the littoral zone of the lake. 19 morphometric characters were measured using a digital caliper, then each fish sample was weighed. The growth pattern and condition of convict cichlid are known by using the equation of the length-weight relationship and the condition factor. There were 888 individuals of convict cichlid caught during this study, consisted of 385 fish from Tamblingan Lake, 371 fish from Buyan Lake, and 132 fish from Beratan Lake. Moreover, 108 fish consisting of 36 fish from each lake were further analyzed by measuring 17 additional morphometric characters. The results of measuring the morphometric characters of the observed convict cichlid had different variations for the characters of head length and predorsal length. There was diversity for several morphometric characters of the convict cichlid in Buyan Lake which are a collaboration of characters between the convict cichlid in Tamblingan Lake and in Beratan Lake, namely on the basic characteristics of the anal fin, dorsal fin base, body length, postorbital length, and tail height. The growth pattern of this species in the three lakes was negative allometric and the condition of this fish species was in good condition with the average value of condition factor ranging from 0.95–1.05.

Spatial Variability of Morphometric Characters of Freshwater Food Fishes from River Ganga of Districts, Kanpur, Prayagraj and Varanasi of Uttar Pradesh, India

The morphometric characters were evaluated to assess the population status of the commercial valuable food fishes collected from River Ganga at three different locations, Kanpur, Prayagraj and Varanasi. In this study, seventeen morphometric parameters were considered to examine during the month of October, 2022 to January, 2023. Usually, the various species of fishes consumed from the river Ganga. For present study, the morphometric characters like total length, fork length, standard length, pre-orbital length, post-orbital length, eye diameter, head length, pre-pectoral length, pre-dorsal length, pre-pelvic length, pre-anal length, length of dorsal fin, length of pectoral fin, length of caudal fin, length of caudal peduncle, body depth and body weight of four fish species, Labeo rohita, Rita rita, Wallago attu and Cyprinus carpio examined. A total of 25 specimens of each species were collected and the quantitative measurement of each aforesaid morphometric character provided crucial data regarding the development of fish body parts. Additionally, the positive correlations have been significantly (p < 0.01 and p < 0.05) detected amongst the selected morphometric characters of fishes. This study will be very crucial for fisheries management. Also, the findings will distribute the important standards for the geographical distribution of the commercially valuable food fishes. Further, the study defines that the growth of all fishes is suitable and the river Ganga ecosystem on three sites, Kanpur, Prayagraj and Varanasi is enormously favourable to the aquatic fauna especially fishes.

Morphometric analysis of fish, Labeo rohita in Lucknow, Uttar Pradesh, India

A study on morphometric characters of Indian Major Carp- Labeo rohita was conducted and the fish were collected from the fish markets of Lucknow. Labeo rohita, commonly known as rohu is a species of fish that belongs to the family Cyprinidae and the order Cypriniformes. It is a warm water teleost and primarily feeds as a column feeder herbivore. Ten morphometric characters, length-weight relationship of Labeo rohita were studied. The morphometric measurements like total length, standard length, head length, snout length, body depth, eye diameter, pre-dorsal length, pre-pelvic length, pre-pectoral length and caudal length and body weight were recorded. The descriptive statistical parameters and correlation coefficient were analysed with independent and dependent variables. The morphometric character showed gradual increase in the body length and weight. A positive correlation has been observed between total length and other morphometric characters like standard length, head length, snout length, body depth, eye diameter, pre-dorsal length, pre-pectoral length, pre-pelvic length, caudal length. The value of ‘b’ of the length-weight equations is 3.949 which suggest that fish possess positive allometric growth.

A new species of the congrid eel genus Conger (Anguilliformes: Congridae) from the southwest coast of India

A new species of Conger eel is described from a single specimen (569 mm total length) collected off Kanyakumari, Southwest coast of India, Arabian Sea. The following characters distinguish the new species from other congeners: dorsal-fin origin behind the pectoral-fin tip; head larger, 18.5% TL; longer predorsal length 24.0% TL; relatively shorter trunk, uniserial teeth at the posterior end of vomerine patch; body blackish to dark brown; pectoral fin completely darker; cephalic pores rim whitish; SO pores 3; IO pores 6; pectoral rays 19; total vertebrae 141+. Genetic analysis of the mitochondrial COI gene revealed that the new species is closely related to Conger verreauxi Kaup, 1856 and Conger macrocephalus Kanazawa, 1958, with a genetic divergence of 5.7% and 5.9% respectively.

Morphometric and Meristic Diversity in Eel (Anguilla bicolor) in South Coast of Java

Indonesia is the largest exporter of eel to consumer countries such as European, America, Taiwan, Japan, South Korea, and the Middle East. Eels are catadromous fish that are in the growth phase in fresh waters and the development phase is in marine waters. Meristic measurement is done by counting the spine (vertebrates). Eel morphometric measurements include TL (Total Length), HL (Head Length), PDL (Pre-Dorsal Length), PAL (Pre-Anal Length) and ADL (Ano-Dorsal Length). The purpose of this study was to analyze the morphological, morphometric, and meristic diversity of intraspecies between populations. Based on the research, the samples identified were morphologically almost the same between the populations, this was seen from the color patterns in the form of plain black or brown and short fins. The morphometric and meristic measurements in the 3D distribution plot still appear to be clustered in one population, while in the dendrogram clade, one species is still congregated in each. The results of the interpretation of the matrix plot of the lowest diversity are the length and number of anodorsal vertebrate segments. This observation can be concluded that the TL and TV of the eel varied, while the PDL, PAL, PDV, PAV, ADV showed the intraspecies character of A. bicolor. This is because the distribution of A. bicolor eels that inhabit the waters of Java Island is widely distributed and random (panmitic).

COMPARATIVE MORPHOMETRIC, MERISTIC AND OSTEOLOGICAL STUDIES ON ADULT AND YOUNG HILSA (TENUALOSA ILISHA)

Tenualosa ilisha (matured/adult) and jatka (immature/young), locally known as Ilish, is designated as the national fish of Bangladesh. Both the stages were collected from different fish markets from Savar, Bangladesh during the exploration. This study was carried out on comparative morphometric, meristic and osteology between the Tenualosa ilisha (matured) and jatka (immature/young). The morphometric characteristics were higher in matured Tenualosa ilisha than immature jatka and among them head length, pre-dorsal length, postorbital length, the height of anal fin, eye diameter length, and abdominal region length were found significantly different. The proportion of standard length and snout length, head length and snout length, abdominal region length and standard length were significantly different between the two stages. Among the meristic characteristics; number of dorsal fin rays, anal fin rays and scales on the lateral line were found with little differences between matured hilsa and jatka. There are very small differences in the number of scales, scutes and fin rays of different fins between the two stages of fishes. The osteological comparison reveals more or less identical structure. Most of the bones of the skull were similar in structure but differed in size, shape and thickness.

Additional Data on Arctozenus australis Ho et Duhamel, 2019 (Pisces: Aulopiformes, Paralepididae) off Kerguelen Islands

This work clarifies the morphological data for the recently described species Arctozenus australis Ho et Duhamel, 2019. Specimens caught in the northwest of the known range of the species confirm the validity of diagnostic characters and expand the known range of the following parameters: predorsal length, prepelvic length, preanal length, distance between origins of dorsal and anal fins, head depth, distance between origins of dorsal and pelvic fins, interorbital width, caudal-peduncle depth, snout length, upper-jaw length, lower jaw, number of caudal vertebrae, preanal vertebrae, and anal fin rays.

An application of morphological analysis and DNA barcoding to identify Ipnops from the Clarion-Clipperton Zone (CCZ) as I. meadi Nielsen, 1966 with notes on other species of the genus (Aulopiformes: Ipnopidae)

Although Ipnops specimens are relatively common in the Clarion-Clipperton Fracture Zone (CCZ), an area targeted for potential future deep-sea mining, a reliable species identification has not yet been possible due to the lack of a captured specimen. In April 2012, an Ipnops specimen was caught for the first time from the eastern CCZ during an exploration cruise of the BGR. Species identification of this specimen was performed using a comparative application of morphological analysis and DNA barcoding and resulted in its clear assignment to Ipnops meadi Nielsen, 1966. Of the 23 compared morphological characters, 22 are inside the ranges available for I. meadi. Molecular analyses show a sequence distance of 0.76% divergence to an Ipnops specimen collected off Hawaii, close to the CCZ and also within the known geographical distribution range of I. meadi. The additional study of five specimens of I. meadi from the Arabian Sea has extended the previously known range of the following morphological characters of this species: gill rakers on anterior arch (17–21), head length (17.6–24.0 % SL), upper jaw length (10.7–14.0 % SL), maximum width of eye-plates (7.8–9.8 % SL), preanal length (58.8–79.0 % SL), and predorsal length (34.5–40.5 % SL). Ipnops specimens deriving from Australian waters could not be clearly assigned with confidence to one of the valid Ipnops species based on current morphological and molecular analyses. It seems possible that at least one previously undescribed Ipnops species occurs in Australian waters and further work is required on the genus to resolve uncertainties.

Pseudolaguvia meghalayaensis, a new diminutive sisorid catfish (Teleostei: Siluriformes) from Northeastern India

Pseudolaguvia meghalayaensis, a new diminutive sisorid catfish, is described from the confluence of Rongkil and Rongdal streams (tributaries of the Brahmaputra River) in Meghalaya, India. It is distinguished from its congeners by a combination of characters: striae in thoracic adhesive apparatus strongly anastomosing and break up into small rounded plaques posteromedially, smooth anterior edge of dorsal spine, 8 branched pectoral-fin rays, supraoccipital spine not reaching nuchal shield, pectoral-fin length 17.120.1% standard length (SL), predorsal length 40.443.8% SL, preanal length 71.173.1% SL, body depth at anus 15.618.1% SL, anal-fin base length 12.212.7% SL, and post adipose fin length12.312.6% SL.

Early development of pearlside Maurolicus stehmanni off south-eastern Brazil.

The pearlside Maurolicus stehmanni is one of the most abundant mesopelagic fishes off south-eastern Brazil and plays a key role in the regional ecosystem. However, its early life history remains poorly understood. This study examined the M. stehmanni early life stages, from eggs to juveniles, including all developmental changes in external morphology. Larvae are simple in morphology and lack specialized larval structures. Notochord flexion begins at ~5.15 mm body length (BL) and larvae ≥5.95 mm BL are flexed. The relative growth of seven measured larval characters (head length, body depth, snout length, eye diameter, pre-dorsal length, pre-ventral length and pre-anal length) have transition points (allometric inflexion points), indicating biphasic growth patterns which are likely related to shifts in habitat use, feeding and behaviour. Larval development is similar to that of other Maurolicus species. The relatively fast development of the fins, photophores, swimbladder and pigmentation suggests a precocious adoption of a micronektonic lifestyle in the mesopelagic environment.

KERAGAMAN BENIH SIDAT DAN SIDAT DEWASA (Anguilla sp.) DI SUNGAI DUMOGA, SULAWESI UTARA

The spawning sites of Anguilla borneensis and Anguilla celebesensis were in the seas off Sulawesi and the Gulf of Tomini, the spawning sites of Anguilla marmorata and Anguilla bicolor pacifica were in the western part of the North Pacific. The purpose of this study was to find out information on the diversity of eel seeds and adult eels in the Dumoga River based on the abundance of eel seeds and gonad maturity of adult eels. The eel species consisted of 1,106 A. marmorata, A. bic. pacifica as many as 854 tails and Anguilla spp as many as 291 individuals. The caught eel fish were separated based on the morphology of the eel species. Segregation of catches based on special characteristics of eel, namely preanal and predorsal lengths. Anodorsal values were divided into three groups, namely ±15.57% (A. marmorata); ±1.18% (A. bicolor pacifica) and ±7.09% (Anguilla spp.). Meristic values of A. marmorata for spine (TB) total 104-106 units, pre-dorsal TB 17-19, pre-anal TB 36-39 and ano-dorsal TB 18-20. Meristic values of A. bicolor pacifica for spine (TB) totaled 108-112, pre-dorsal TB 32-36, pre-anal TB 32-39 and ano-dorsal TB 0-3. Meristic values of Anguilla spp for spinal (TB) totaled 100-106, pre-dorsal TB 27-29, pre-anal TB 30-33 and ano-dorsal TB 6-12. The growth pattern of adult eels is negative allometric, i.e. the body length gains faster than the slower body weight gain. The condition of adult eels in the Dumoga River is not fat because the condition factor ranges from 0.0024-0.0036. The average length of adult eels was 58.92cm in Anguilla marmorata (GIC 1.57–2.90%); 54.2cm in A. bicolor pacifica (ICI 1.27–2.79%) and 52.32cm in Anguilla spp (ICI 0.97-2.50%).

A new species of leaf fish, Nandus banshlaii (Perciformes: Nandidae) from West Bengal, India

Nandus banshlaii, sp. nov. described from the Banshlai River of West Bengal. This species is distinguished from all its congeners in having a golden brown body in live and a combination of characters like longest head and snout length (44.28% SL and 35.58% HL respectively) and from its two Indian congeners in containing largest eye diameter (22.22% HL), longest pre-dorsal length (47.16% SL), shortest pectoral fin length (14.60% SL) and smallest dorsal fin base length (45.53% SL).Like all three congeners of Ganga-Brahmaputra-Meghna river basin of Gangetic delta it possess a dark spot on caudal peduncle. To differentiate the present species from other two Indian congeners of Nandus, N. nandus and N. andrewi, PCA and heatmap is performed and a key of all three species is also provided.

Schindleria parva, a new species of Schindler's fish (Teleostei: Schindleriidae: Schindleria) from Jeddah, Saudi Arabia, Red Sea.

Schindleria parva, a new species of the family Schindleriidae, is described from two specimens collected from the central Red Sea of Saudi Arabia. The new species is characterized by lack of pigmentation on the body, possession of an inconspicuous gas bladder and the presence of small teeth on the premaxillae. The holotype is a female of 11 mm standard length (SL) (11.9 mm total length) and the paratype is a male of 9 mm SL. Dorsal fin rays 10 (9) anal fin rays 9 (7). The body depth at pectoral-fin origin 5% (4%) of SL, depth at anal-fin origin 8% (7%) SL, predorsal length 63% (65%) SL, preanal length 72% (72%) SL, the first anal-fin ray situated below the fourth dorsal-fin ray), a total of 23 + 16 myomeres. The female contained a series of 30 rectangular eggs in a single row, whereas the male is characterized by a short rod-like urogenital papilla. Species of the genus Schindleria are likely the smallest marine vertebrates on the planet and S. parva is likely the smallest Schindleria species in the Red Sea. The global diversity of Schindleria is likely underestimated due to the paedomorphic features of this genus. Its fast generation times make it a species-rich genus of high turnover rates, thus potentially highly important for the trophic food webs of coral reefs. Thus, this finding advances knowledge on the biodiversity of the Red Sea, highlights its conservation significance, and contributes towards the understanding of the complexity of the coral-reef fish community.

Multivariate morphometric study for species differentiation in two congeneric schizothoracids, Schizothorax niger Heckel 1838 and Schizothorax esocinus Heckel 1838 from River Jhelum Kashmir

Principal component and discriminant analyses were used to investigate morphological differences between Schizothorax niger Heckel 1838 and Schizothorax esocinus Heckel 1838 from River Jhelum, Kashmir, India. The purpose of this study was to identify the two species correctly and assign them into distinct genetic groups. Seven morphometric measurements (body weight, standard length, total length, head length, body depth, pre-dorsal length and caudal fin length) were studied in 100 fish specimens. All the studied morphometric characters reported higher mean values (p<0.01) in S. niger. The use of multivariant techniques such as principal component analysis, showed that the differences between the species resulted mainly from body weight, standard length, pre-dorsal length, head length, total length and caudal fin length. The stepwise discriminant analysis revealed that morphometric traits namely, standard length, pre-dorsal length and caudal fin length were the three most important variables to clearly distinguish the two species. Cross validation test using leave-one-out procedure indicated that 89% original grouped cases correctly classified into their groups, whereas 89% of cross validated grouped cases were correctly classified. Keywords: Fish stocks, Morphology, Schizothorax, Snow trout, Variation

Morphological measurements, length weight relationship and relative condition factor (Kn) of Obtuse barracuda Sphyraena obtusata (Cuvier, 1829) from South-eastern Arabian Sea

The study investigated morphometric and meristic measurements, length-weight relationship (LWR) and relative condition factor (Kn) of the Sphyraena obtusata from south-eastern Arabian Sea from August 2019 to March 2020. Three hundred and fifty two specimens having a length and weight range of 16.5 – 30.1 cm and 29.54 – 155.20 g, respectively were analyzed for morphological measurements (13 morphometric and 11 meristic), LWR and relative condition factor. The maximum correlation were existed between standard length (r > 0.985), fork length (r > 0.979) and pre-dorsal length 1 (r > 0.942) among the various morphometric variables. A disparity in relative growth was noticed among the morphometric traits. The Regression coefficient b value clearly indicates that growth of all the morphometric characters were isometric in connection with the total length, except for pelvic length (negative allometric), body depth (positive allometric) and caudal depth (positive allometric) (p < 0.01). The length-weight relationship of the individual sexes (male, female) and pooled data is indicated as W = 0.02275 L2.6033, W = 0.01786 L2.6815 and W = 0.01945 L2.6541 having the value of coefficient of determination (r2) as 0.9566, 0.9696 and 0.9658, respectively. The ‘b’ values for both males and females divulge negative allometric growth (p < 0.05). There was no significant difference for the relative condition factor (Kn) among the months and size groups.

A new species of Gymnelus (Perciformes, Zoarcidae) from Greenland, similar to G. viridis

Zoarcid fishes of the genus Gymnelus Reinhardt inhabit the shelves of the North Pacific Ocean and the Arctic. A new species, G. pseudosquamatus sp. nov., is described from trawl samples taken at depths off South-West Greenland. It is most similar to the type species of the genus, Common Fish Doctor G. viridis, inhabiting the coastal waters of Greenland. The characters of the latter are specified on materials from the type locality, including the neotype and specimens of J.C.H. Reinhardt. Both species are in the group of Gymnelus with an interrupted supratemporal commissura, two supratemporal sensory pores (1+0+1), and a dorsal fin originating above the pectoral fin. The two species differ in a complex of characters, including habitus. In G. viridis, the trunk is roundish in cross section, highest above the beginning of the anal fin; the anterior rays of the dorsal fin are shortened, and covered with a thick and somewhat fleshy skin. In G. pseudosquamatus, the body is compressed and deeper anteriorly, the dorsal-fin rays are evenly elongated, and the fin membrane is thin. Differences in counts and measurements are statistically significant, including the number of vertebrae and rays in the dorsal, anal and pectoral fins, the number of teeth on the jaws, as well as the length and depth of the head, predorsal length, the length of pectoral fins, eye diameter and length of the gill slit. The color of G. pseudosquamatus, with 8–16 wide brown mottled bands, is also unusual, as the skin is dotted with light speckles that create the illusion of tiny scales, which is the reason for the name “pseudosquamatus”, the Deceptive Fish Doctor. While G. viridis is found inshore in a zone of macroalgae, the new species is found in deeper waters (100–457 m) along the shelf edge of South-West Greenland. The name Ophidium stigma Lay et Bennett, 1839 (=Gymnelus stigma) should be excluded from the synonymy of G. viridis, since the original description mentions the presence of scales on the body, which are absent in Gymnelus.