Dorsal-fin Base Research Articles

A new record of a rare labrid, Suezichthys notatus (Actinopterygii: Labridae), from Taiwan, with comparison to related species from Taiwan

Three specimens of a rare labrid, Suezichthys notatus (Kamohara, 1958) were recently collected from local markets, which were captured from deep-water off northern and southwestern Taiwan, and represent a new record for Taiwan. Suezichthys notatus can be distinguished from its congeners by a combination of characters: scale rows above lateral line 2½; low scaly sheath present at base of dorsal and anal fins; dorsal-fin element IX, 11; anal-fin elements III, 10; lateral line scales 25‒26, each with simple, unbranched laterosensory canal tube; cheek scale rows behind and below eye 2 and 2‒3 respectively; a group of prominent dark blotches extending from the interorbital region dorsoposteriorly; body depth at dorsal-fin origin 3.7‒3.9 in standard length; short pelvic fin without filamentous extension, 2.2‒2.5 in head length. Suezichthys resembles the labrid genus Pseudolabrus, comparison of Taiwanese species of Suezichthys with those of Pseudolabrus are given.

Morphology characteristics and length weight relationship of sucker barb fish (Barbichtyhys laevis Valenciennes 1842)

Sucker barb fish is one of the potential of fish resources in Tasik river. This study aimed to determine the morphometric and meristic characteristics of the growth of sucker barb fish in the Tasik River. The method used in this study is a survey method using the fishing net and gillnet with mesh size 1,5 inches. The nets are placed in the afternoon, then lifted in the morning. This is done 3 times with a span of 2 weeks in the three research stations. The number of samples collected were 135 fish. The morphometric characteristics of sucker barb fish are bodyweight (BT) ranging from 9-85 g, total length (PT) ranging from 100-230 mm, standard length (PS) ranging from 75-176 mm, head length (PK) of 20-42 mm, snout length (PM) of 30 mm, the height of dorsal fin (TSP) of 40 mm, length of the base of dorsal fin (PPSP) of 15-30 mm, eye diameter (DM) of 10 mm, caudal peduncle (TBE) of 8-22 mm, body height (TB) of 17-40 mm, pectoral fin length (PSD) of 30 mm and pelvic fin length (PSP) of 25 mm. Meristic characteristics are the characteristics of counting the scales and fins of sucker barb fish. The number of scales in the lateral lines (LL) is 35-38, the body coiled scales (SMB) are 6, the scales around the pectoral fin (PF) P 10-14, anal fin (AF) A 8 and caudal fin (CF) C 18. The growth pattern of sucker barb fish in the Tasik River is allometric negative

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.

Analysis of sustainable biological aspects of Scottish seine net in the waters of Majene, Indonesia

Ministry of Marine Affair and Fisheries decree No.2 of 2015 states that the Scottish seine net is one of the fishing gears that is prohibited because the size of the fish catches were not suitable for catching. The purpose of this study was to evaluate the Scottish seine net fishing gear on the technical and biological aspects. The method used in this research is the survey method on the Scottish seine net and direct measurement of fork length and body circumference at dorsal fin base. The analysis used in this study is a description equipped with a graph, gonad maturity levels were analysis morphologically, determination of the first gonad maturity size using the Udupa method. The shortfin scads fish is the dominant fish caught in the Majene waters. The results showed that most of the scads caught by the Scottish seine net were fit for catching. The size of the fish that is suitable for catching depends on the position of the fishing area. The further away the fishing area is from the coastline, the larger portion of fish suitable for catching. The first gonads mature of shortfin scads fish in Majene waters in the fork length range of 205 – 208 mm for males and 211 – 216 mm for females. In order to catch shortfin scads fish that is suitable for catching, the minimum mesh size is 59.5 m for gill nets, and 39.7 mm for fishing gear that does not entangle.

An investigation on systematic history and distribution areas of tarek (Alburnus tarichi (Güldenstädt, 1814))

This study aimed to determine the distribution area of tarek (Alburnus tarichi (Güldenstädt, 1814)) and to define how it must be called according to the scientific name by evaluating its previous studies made by various systematisers and their reports on its distribution, and by comparing literature knowledge. The taxonomic characteristics of the collected samples were evaluated and several measurements and counts were taken on the samples; analfin origin 0-4 scales behind dorsal fin-base; 72-91 lateral line scales; 21-29 gill rakers; 7½-10 branched dorsal-fin rays and 10-12½ branched anal-fin rays. Body and caudal peduncle was moderately compressed. Body was covered by overlapping scales. Tarek has five different populations in the Basin. They are Van, Erçek, Nazik and Aygır Lakes and Koçköprü Dam Lake populations. The main living area of the tarek population is Lake Van; however, between May and June, mature individuals of tarek enter to tributaries of Van Lake. Some of them are Karasu, Bendimahi, Deliçay, Zilan, Karmuç, Sapur, Yanıkçay, Gevaş, Engil, Kurubaş and Akköprü Streams. At the end of study, it was concluded that tarek should be called as Alburnus tarichi (Güldenstädt, 1814) and it is an endemic fish species distributed only in Van Lake Basin.

Determination of the average intraocular pressure values, optimum anesthesia dose and phenotypic characteristics in Oscar fish (Astronotus ocellatus)

This research was carried out to determine the intraocular pressure values, optimum anesthesia dose and phenotypic characteristics in Oscar fish (Astronotus ocellatus). A total of 11 adult, male Oscar fish were used in the study. Optimum anesthesia dose, pre-and post-anesthesia intraocular pressure values and phenotypic measurements (total length, fork length, standard length, dorsal fin base length, head length, body length, eye diameter, body depth, pectoral length, pelvic fin bottom length, anal fin bottom length) were determined and reference values specific to this fish species were obtained by performing a statistical analysis. When exposed to 3 cc/L of the concentrations, fish achieved a deep state of anesthesia (induction time 1.31 min; recovery time 6.42 min). The most balanced anesthesia without risking vital functions was achieved using Clove oil with a dose of 2.5 cc/L. Compared to the other dimensions, total length, fork length and standard length were the most consistent body measurements with high positive correlations. No statistically significant difference (p > 0.05) was seen in both eyes between the intraocular pressure values before (5.36-5.86) and after (5.59-5.36) anesthesia. It is recommended that the ideal concentration of clove oil was 2.5 cc/L to reduce stress and injury damage during handling procedures. Additionally, intraocular pressure values, body measurements and Clove oil optimum anesthesia dose obtained in this study can be used as reference values for Oscar fish raised in aquarium conditions.

Chronosequence of morphological change in a stream fish following impoundment

Abstract Water impoundment is among the most prevalent and potent forms of anthropogenic environmental modification worldwide. Flow modification can drive morphological changes in riverine species that persist after dam closure, but little is known about the tempo and trajectory of phenotypic responses to impoundment. Through geometric morphometric analysis of natural history collections from behind Claiborne Lock and Dam (i.e. in Claiborne Lake reservoir) and nearby Chilatchee Creek (Alabama River Basin, Alabama, U.S.A.), we reconstructed multidecadal chronosequences of morphological change in a stream fish (Cyprinella venusta Girard) to characterise phenotypic responses to impoundment and unrestricted flow. We then conducted cross‐correlation analysis of hydrological and morphological time series to determine whether morphological responses to impoundment are consistent with expected outcomes of evolution, phenotypic plasticity, or some combination thereof. We found evidence of marked phenotypic change shortly after impoundment. Within a year of dam closure, individuals from Claiborne Lake exhibited a reduction in head size, an increase in body depth, and a decline in the length of the dorsal fin base, with further responses becoming apparent c. 6 years thereafter. The morphology of individuals from the nearby stream consistently differed from individuals in the reservoir. We found that fish from Chilatchee Creek exhibited gradual directional shifts and morphological fluctuations over time, which differed from patterns of change observed in C. venusta from Claiborne Lake. There also were indications of multidecadal lags at both sites, probably reflecting common responses to periodic climatic variation that were mitigated by site‐specific differences in physiography and ecology. Our findings are consistent with the hypothesis that impoundment can elicit punctuated responses attributable to within‐generational phenotypic change and rapid evolution over as few as two generations. Our findings also indicate that hydrological variation in unrestricted streams can elicit pronounced shifts in body shape, suggesting that space‐for‐time substitutions may not effectively capture the nature of responses to flow modification. Additional investigations based on more extensive and complete chronosequences would further illustrate the value of natural history collections and offer more insight into the mechanistic basis of biotic responses to environmental change.

Molecular phylogeny of the Austrolebias/ adloffi/ group (Cyprinodontiformes, Rivulidae), with description of two new endangered and highly endemic species of annual killifishes from the Laguna dos Patos system, southern Brazil.

The Austrolebias adloffi species group encompasses a diverse lineage of annual killifishes that occurs along the Laguna dos Patos/Lagoa Mirim system, in both Brazilian and Uruguayan territories. We herein employ an integrative taxonomy approach to describe two new species of the group, inferring their phylogenetic relationships and evaluating their conservation status. Austrolebias cheffei sp. nov. and Austrolebias lourenciano sp. nov. are herein described from the western portion of the Laguna dos Patos system. Austrolebias cheffei is distinguished from the remaining species of the A. adloffi species group by presenting a yellowish green or yellowish blue dorsal fin, with wide black to dark brown bars extending from the base to the middle portion of the dorsal and anal fins in the males. Austrolebias lourenciano is distinguished from the remaining species of the A. adloffi species group by presenting a yellowish green dorsal fin, with light yellow or light bluish bars forming small triangles, interspersed with small dark brown rows of blotches in the dorsal fin base, and greenish blue anal fin, sometimes with lighter elongated yellowish iridescent blotches, limited to the basal region. According to mitochondrial cytb sequences, both species are reciprocally monophyletic relative to other species of the A. adloffi species group, and present positive barcoding gap values. Interestingly, both new species form a grade that is closely related to Austrolebias aff. minuano 1, an undescribed species that occurs at the opposite margin of the Laguna dos Patos. Among the other evaluated species, A. bagual, A. aff. minuano 1, A. nigrofasciatus, A. pelotapes, A. pongondo, A. arachan, and A. viarius also revealed to be reciprocally monophyletic, whereas A. minuano and A. adloffi revealed to be paraphyletic in regard to A. charrua and A. aff. minuano 2, respectively, and A. nachtigalli is subdivided in two clades, one of which including A. reicherti, which points to the need of a taxonomic review of the group. In addition, we discussed the conservation status of the new species, corrected the type locality of A. pongondo, and provided a dichotomous identification key of the A. adloffi species group.

Visualization of Sox10-positive chromatoblasts by GFP fluorescence in flounder larvae and juveniles using electroporation.

Japanese flounder are left-right asymmetrical, with features, such as dark, ocular-side specific pigmentation. This pigmentation arises during metamorphic stages, along with the asymmetric differentiation of adult-type chromatophores. Additionally, among juveniles, tank-reared specimens commonly show ectopic pigmentation on their blind sides. In both cases, neural crest-derived Sox10-positive progenitor cells at the dorsal fin base are hypothesized to contribute to chromatophore development. Here, we developed a method to visualize Sox10-positive cells via green fluorescent protein (GFP) fluorescence to directly monitor their migration and differentiation into chromatophores in vivo. Electroporation was applied to introduce GFP reporter vectors into the dorsal fin base of larvae and juveniles. Cre-loxP system vectors were also tested to enable cell labeling even after a decrease in sox10 expression levels. In larvae, undifferentiated Sox10-positive progenitor cells were labeled in the dorsal fin base, whereas newly differentiated adult-type chromatophores were seen dispersed on the ocular side. In juveniles, Sox10-positive cells were identified in the connective tissue of the dorsal fin base and observed prominently in areas of ectopic pigmentation, including several labeled melanophores. Thus, it was suggested that during metamorphic stages, Sox10-positive cells at the dorsal fin base contribute to adult-type chromatophore development, whereas in juveniles, they persist as precursors in the connective tissue, which in response to stimuli migrate to generate ectopic pigmentation. These findings contribute to elucidating pigmentation mechanisms, as well as abnormalities seen in hatchery-reared flounders. The electroporation method may be adapted to diverse animals as an accessible gene transfer method in various research fields, including developmental and biomedical studies.

Types of Sex And Development of Gonad Protoginic Rice Grouper (Cromileptes altivelis) After Hormone Stimulation

This study aims to analyze the effect of estradiol (E2) and methyltestosterone (MT) combined with hCG on the composition of sex and the gonad development of protogynous humpback grouper ( Cromileptes altivelis). The fish experiment 13 ±1 , 5g of body weight in the nursery phase . Treatment with a estradiol solution of 3 mg mL –1 + hCG 2 0 IU mL –1 ( CE), MT 3mg mL –1 + hCG 2 0 IU mL –1 ( CM), estradiol 3 mg mL –1 ( E), MT 3 mg mL –1 (M) and 9 mg mL –1 NaCl to control ( K ) . Hormone with dose 1 mL kg –1 was injected on dorsal fin base , with frequency of six times and period e of two weeks. The fish are kept in a 500 liters fiberglass container with a calm water system for 11 months. Fish were fed pellets with protein content of 46% twice daily. The study used a completely randomized design with one treatment factor, the hormone and its combination. Giving hormones with combination , i.e. treatmenth C E and CM was effective to increase the percentage of gonad development with GSI value 0 .4161 ±0.0978 % and 0.4161 ±0.1055 %, whilw HSI on CE 0.6456 ± 0.0419% and CM 0.5797 ± 0.1069% The gonadal histologic observation showed transition pattern and sex change from female to male at treatment M and CM. The MT hormone is able to stimulate masculinization and its performance is more effective when combined with hCG, 90% from sample population. The development of female gonads in the phases of oogonia and male of masculinization result in the phase of spermatogonia.

First record of two squirrelfishes, Sargocentron spinosissimum and Sargocentron tiereoides (Actinopterygii, Beryciformes, Holocentridae) from the Egyptian Mediterranean coast

Holocentrinae and Myripristinae (Holocentridae) are among the most apparent species in the nocturnal reef fish community. However, there is no clear assent regarding their phylogenetic relations, which is reported in their complicated taxonomic history. In this study, Sargocentron spinosissimum (Temminck et Schlegel, 1843) and Sargocentron tiereoides (Bleeker, 1853) were reported from the Mediterranean coast of Egypt (Damietta coast). This is the first record of these species which is greatly distributed across Indo-Pacific regions and eastern Africa showed the success of these species to migrate to the Mediterranean water with a good adaptation to the new habitats. In the presently reported study, 26 morphometric measurements were recorded and cytochrome c oxidase subunit I (COI) barcodes were recovered for a total of 20 specimens (8 from S. spinosissimum and 12 from S. tiereoides). The specimens from the Damietta coast, Egypt show character states diagnostic of S. spinosissimum: Head is curved. Spinous dorsal fin base straight. Soft dorsal fin base slightly raised. Spinous dorsal fin membranes red. Anterior margin of pelvic and anal fins white. Other fin rays are red. While character states diagnostic of S. tiereoides: Head is straight and pointed. Spinous dorsal fin base almost straight. Soft dorsal fin base not raised and spinous dorsal fin membranes vaguely red. Sequences of both species were submitted to the GenBank and Barcode of Life Database (BOLD) publication database which displayed 99%–100% similarity value S. tiereoides from GenBank and BOLD databases but, S. spinosissimum has not any deposited sequences from GenBank or BOLD. DNA barcoding based on COI gene was demonstrated as a powerful and useful molecular marker in the identification and differentiation of S. spinosissimum and S. tiereoides fish species.

Chimaera compacta, a new species from southern Indian Ocean, and an estimate of phylogenetic relationships within the genus Chimaera (Chondrichthyes: Chimaeridae)

Chimaera compacta sp. nov., a new species of shortnose chimaera (Holocephali: Chimaeriformes: Chimaeridae), is described from a single specimen collected at 595–655 m depth, off Amsterdam Island, in the southern Indian Ocean. The species is easily distinguished from its congeners by the combination of the following characters: massive head with short snout; stocky and relatively long trunk 44% BDL, short tail with second dorsal fin base 72% BDL; long pelvic fin anterior margin 26% BDL. Caudal fin dorsal origin slightly posterior to caudal fin ventral origin. Firm, non-deciduous skin; brown color with yellow blotches. Chimaera compacta sp. nov. is morphologically close to Chimaera lignaria Didier 2002 from New Zealand and Chimaera willwatchi Clerkin, Ebert and Kemper 2017 from south western Indian Ocean. The new species can be distinguished from other Chimaera species based on DNA sequences divergence of the COI and NADH2 genes. This species has a nucleotide sequence divergence (uncorrected p distances) for the studied genes of 4.2 and 4.1%, respectively, with its closest relatives. Phylogenetically, Chimaera compacta sp. nov. is nested within a well-supported group including Chimaera carophila Kemper, Ebert, Naylor and Didier 2014, Chimaera didierae Clerkin, Ebert and Kemper 2017, C. lignaria, Chimaera macrospina Didier, Last and White 2008, Chimaera notafricana Kemper, Ebert, Compagno and Didier 2010, Chimaera opalescens Luchetti, Iglesias and Sellos 2011, and C. willwatchi. It is the first Chimaeridae described for the Territory of the French Southern and Antarctic Lands.

Acropoma musorstom, a new lanternbelly (Acropomatidae) from the South Pacific and the first record of Acropoma splendens from the Andaman Sea off southwestern Thailand

A new species of the genus Acropoma, A. musorstom sp. nov. is described based on four specimens (126.3–143.0 mm in standard length: SL) collected from Vanuatu and the Molucca Islands, Indonesia. The present species is distinguished from other congeners by a combination of the following characters: luminous gland short, U-shaped around anus; luminous-gland length 10.3–13.7% SL; symphysis of lower jaw not protruded; proximal radial of first anal-fin pterygiophore with concavity on anterior surface; anus situated closer to pelvic-fin insertion than to origin of anal fin; weakly ctenoid scales on lateral side of body; vertical line on cheek absent; scales between first dorsal-fin base and lateral line 4; pectoral-fin rays 16–17; and gill rakers 20–21. Acropoma splendens (Lloyd 1909) collected from off Phuket, it represents the first record of this species from the Andaman Sea off southwestern Thailand. A key to the species of Acropoma currently known from the Indo-Pacific is provided.

Two new species of the genus Chelidoperca (Perciformes: Serranidae) from the Andaman Sea, eastern Indian Ocean.

Two new species of the genus Chelidoperca are described from specimens collected in 2015 and 2018 from the Andaman Sea, off the coast of Myanmar during trawl bottom surveys conducted by the R/V Dr. Fridtjof Nansen. Chelidoperca myathantuni sp. nov. is described based on 15 specimens (74.3-129.5 mm SL) from 101-185 m depth, which can be distinguished from all congeners by the following combination of characters: 3 (2 full-sized plus 1 half-sized) scale rows between lateral line and middle of spinous dorsal-fin base; 42-44 (modally 44) pored lateral-line scales; 16 pectoral-fin rays; interorbital scales extending to mid-orbit level; scales on ventral surface of lower jaw restricted to the angular (not extending onto the dentary); enlarged caniniform teeth on the upper jaw; side of body with longitudinal dashed black stripe; dorsal fin pale yellow with reddish pigment mostly restricted at base of spines and rays. Chelidoperca flavimacula sp. nov. is described based on eight specimens (49.7-70.7 mm SL) from 84-131 m depth, which can be distinguished from all congeners by the following combination of characters: 3 (2 full-sized plus 1 half-sized) scale rows between lateral line and middle of spinous dorsal-fin base; 42-45 (modally 42) pored lateral-line scales; 9-10 (modally 10) scale rows below the lateral line; 6 predorsal scales; 16-17 (modally 16) circumpeduncular scales; 5 scales rows on cheek; interorbital scales extending to mid-orbit level; anal fin with yellowish distal margin and three or four rows of bright yellow spots over its proximal half.

Short Communication: Presence of the vulnerable freshwater goby Sicyopus auxilimentus (Gobiidae, Sicydiinae) on Sangihe Island, Indonesia

Abstract. Hasan V, Valen FS, Islamy RA, Widodo MS, Saptadjaja AM, Islam I. 2021. Short Communication: Presence of the vulnerable freshwater goby Sicyopus auxilimentus (Gobiidae, Sicydiinae) on Sangihe Island, Indonesia. Biodiversitas 22: 571-579. A single specimen of freshwater goby Sicyopus auxilimentus was photographed and collected using fish traps between 8 and 15 September 2019 in the Laine waterfall, Sangihe island district, North Sulawesi Province, Indonesia. S. auxilimentus is amphidromous that live in both freshwater and marine environments. This species is currently listed as Vulnerable (VU) within the IUCN Red List Status. The specimen was identified as male S. auxilimentus based on the coloration of the preserved specimen: background yellowish; scale edges brown; posterior flanks and caudal peduncle orange; first dorsal fin black, second dorsal fin dusky black; pectoral fin slightly brown; ventral fin slightly dusky; anal fin blackish; caudal fin dusky brown. Specific morphological features were as follows: the base of the first dorsal fin was not connected to the second dorsal fin base; distance between the base of first and second dorsal fin was generally less than half of eye diameter; ventral fin rays were fused to belly only between fifth rays; posterior margin of caudal fins rays was rounded; scales were all ctenoid; scales appeared on the caudal peduncle, and between anal and second dorsal fins; anterior to which, scales became widely spaced and did not imbricate. Meristic characters were as follows: first dorsal fin rays VI; second dorsal fin rays I+9; ventral fin rays I+5; pectoral-fin rays 14; anal-fin rays I+9; caudal-fin rays 13; scales in lateral series 13; scales in zigzag series 7; scales in transverse series backward 7; scales in transerves series forward 4. This finding is considered the first record in Sulawesi and the fifth from Indonesian waters after findings in Halmahera, Java, Bali and Lombok. This record enhances the understanding of the distribution of S. auxilimentus in Indonesian waters. Monitoring is needed to assess the possibility of Sangihe Island being a growth ground, spawning ground, and/or on the migration route of S. auxilimentus. In the Laine waterfall, Sangihe island, freshwater conditions were as follows: salinity 3.5 psu, temperature 23-25°C, and dissolved oxygen 7.7-9.2 mg/l, which were ideal habitat for S. auxilimentus. S. auxilimentus from Sangihe Island, had 0.000 genetic distance than from S. auxilimentus from Bali, while the next closest genetic distance was S. zosterophorus at genetic distance of 0.090. In addition to onsite conservation, domestication programs are needed to increase commercial availability without depending on natural catches.

A new species of Characidium (Characiformes: Crenuchidae) from the Chapada dos Veadeiros, Goiás, Brazil

Abstract A new species of Characidium is described from the tributaries of the rio Tocantinzinho, rio Tocantins basin, located in the southern portion of the Chapada dos Veadeiros, at about 1,200 meters of elevation, Goiás, Brazil. The new species can be diagnosed by an unusual combination of two apomorphic features present in distinct clades of Characidium, the presence of a scaleless isthmus in allied to with a single row of dentary teeth. Additionally, the new species has a unique color pattern of inconspicuous vertical bars disconnected from the dorsal midline, forming seven to nine square blotches along body sides, and the presence of a dark saddle-shaped mark at the dorsal-fin base. Osteologically, it can be diagnosed by having the first and second anal-fin proximal radials fused and contacting the third hemal spine, which is branched. The new species also has a peculiar, unusual variation of fin-ray counts among its congeners.

The variability of morphometric and meristic characteristics of Urmia chub, Petroleuciscus ulanus (G nther, 1899) in the Mahabd-Chai and Godar-Chai rivers, Lake Urmia basin

Abstract. In this study, for the first time, we provide morphometric and meristic data on Petroleuciscus ulanus from the Lake Urmia basin by comparing them in the populations of the Mahabad-Chai and Godar-Chai rivers. For this purpose, a total of 100 specimens were collected using electrofishing device and cast net during 2014 and 2015. 19 morphometric and 8 meristic traits were measured and counted, respectively. The meristic traits of the two populations showed significant differences in three characters, including branched dorsal and ventral fin rays and lateral line scales (P<0.05). In addition, the morphometric analysis showed significant differences in head length, eye diameter, caudal peduncle length, dorsal fin height and base lengths, pectoral and ventral fin lengths, anal fin base and height lengths (P<0.05). The finding of the current study can help to further studies on the biological features of this endemic species of Iranian inland waters.

Two New Species of Pencil Wrasses (Teleostei: Labridae: Pseudojuloides) from Micronesia and the Marquesan Islands

Pseudojuloides pluto, new species, is described on the basis of the holotype and 11 paratypes from Wake Island, northeastern Micronesia, and nine paratypes from the Maug Islands, Northern Mariana Islands. The new species has previously been confused with Pseudojuloides atavai, but molecular analysis of mitochondrial COI reveals a difference of 6.8% in sequence data between both species, in addition to differences in meristic, morphometric, and coloration details. A second new species, Pseudojuloides proserpina, is described from Fatu Hiva, Marquesan Islands on the basis of the male holotype. The two new species are closely allied to Pseudojuloides atavai, and together form a species complex that differs from other members of the genus in having males that share the following combination of characters: interspinous membrane between the anterior two to three spines of the dorsal fin with a black spot; head extensively reticulate (reduced in P. pluto, new species); dorsal-fin base with a pink stripe; abdominal region behind pectoral and pelvic fins pale lilac to orangey pink (width of this region dependent on species) with a crosshatch or honeycomb pattern; and extensive black coloration over at least posterior half of body. Additionally, females of both P. atavai and P. pluto, new species, are distinctly bicolored (versus unicolored and suffused in all other congeneric species). Although the female form of P. proserpina, new species, is not known, it is likely that it shares this general coloration pattern, which may serve as an additional character uniting members of the Pseudojuloides atavai complex. We briefly discuss the phylogenetic relationships of Pseudojuloides inferred on the basis of mitochondrial DNA.

A small cichlid species flock from the Upper Miocene (9\u201310 MYA) of Central Kenya

Fossil cichlids from East Africa offer unique insights into the evolutionary history and ancient diversity of the family on the African continent. Here we present three fossil species of the extinct haplotilapiine cichlid †Baringochromis gen. nov. from the upper Miocene of the palaeolake Waril in Central Kenya, based on the analysis of a total of 78 articulated skeletons. †Baringochromis senutae sp. nov., †B. sonyii sp. nov. and †B. tallamae sp. nov. are superficially similar, but differ from each other in oral-tooth dentition and morphometric characters related to the head, dorsal fin base and body depth. These findings indicate that they represent an ancient small species flock. Possible modern analogues of palaeolake Waril and its species flock are discussed. The three species of †Baringochromis may have begun to subdivide their initial habitat by trophic differentiation. Possible sources of food could have been plant remains and insects, as their fossilized remains are known from the same place where †Baringochromis was found.

Morphology, biology and parasite fauna of the least cisco (Coregonus sardinella) of the Yenisei River

In the present study, we present an analysis of the morphological and ecological characteristics of the “turukhanskaja” form of the Siberian least cisco of the Yenisei River, including the characters of the size-age, sexual composition of the population, fecundity and growth. The variability of 34 morphological characters was studied. Significant differences were noted between males and females of the least cisco of the Yenisei River for 11 morphometric characters (head length, maximum body depth, caudal peduncle length, antepectoral distance, dorsal fin base length and dorsal fin depth, anal fin base length, pectoral fin length, head width, head (at nape), interorbital width). Significant differences in meristic characters were revealed in comparison of the least cisco from the Yenisei River with populations of Siberian least cisco from other water bodies. It was shown that the Yenisei least cisco is close to the European vendace Coregonus albula Linnaeus, 1758 not only according to cluster hierarchical analysis for some meristic and morphometric features but also in terms of growth and fecundity. In general, the Yenisei least cisco, as well as other populations of least cisco of the Taimyr, is characterized by heterogeneity in the structure of populations. The parasite fauna of Yenisei’s Siberian cisco, captured in the area of Dudinka town, consists of 17 species of parasites from seven systematic groups. It is dominated by Diphyllobothrium ditremum (Creplin, 1825) and Discocotyle sagittata (Leuckart, 1842). The feature of the parasite fauna of least cisco from Yenisei River in comparison with the Ob River (neighbouring water basin) is a low infection with trematodes and a high species diversity of Acanthocephala. The reason for the low infection with trematodes may be differences in the hydrological conditions of the water bodies, which in the Yenisei are unfavourable for the development of intermediate hosts of trematodes. Siberian cisco from the Yenisei River is a carrier of Diphyllobothrium dendriticum (Nitzsh, 1824), a species that can cause human disease.