Relating abundance of purpleback flying squid Sthenoteuthis oualaniensis (Cephalopoda: Ommastrephidae) to environmental parameters using GIS and GAM in south-eastern Arabian Sea

The distribution pattern of purpleback flying squid and the relationship between its abundance and environmental variables in the south-eastern Arabian Sea were analysed using a geographical information system (GIS) and a generalised additive model (GAM). Highest abundances were observed during December and January within 10 and 13°N and 71 and 72°E around the Lakshadweep Islands. The mean abundance in the area was 4.21 tonnes/km² and the maximum sustainable yield (MSY) was estimated as 0.63 million tonnes. GAM indicated that very high squid abundance was associated with low values of dissolved oxygen (6.01–6.27 mg/L), sea surface temperature (28.03–28.62°C), pH (7.75–8.56), salinity (30.42–34.48 psu), chlorophyll-a (0.4–0.6 mg/m³), zooplankton biomass (0.23–0.64 mL/m³), and shallow 20°C isotherm (101.2–134.7 m) and mixed layer depth (17.8–29.8 m). As a carnivore from paralarval stages, S. oualaniensis depends on secondary and tertiary production to sustain its population for which primary production is used up. In the tropical Arabian Sea where temperature differences are not so pronounced, S. oualaniensis distribution was found to be related to a low but very narrow sea surface temperature (SST) band. There is sufficient fishable biomass in the area to possibly launch a new targeted oceanic squid fishery from the western seaboard of India.     

Calanoides natalis Brady, 1914 (Copepoda: Calanoida: Calanidae): identity and distribution in relation to coastal oceanography of the eastern Atlantic and western Indian Oceans

Until recently, Calanoides carinatus s.l. was assumed to be very widespread in the upwelling systems of the Atlantic, Indian and western Pacific Oceans. Molecular data, reported here, show that Calanoides from the eastern Atlantic and Arabian Sea are one species and distinct from C. carinatus s.s. The name Calanoides natalis Brady, 1914 is available for this species, which is fully re-described. The illustration by Brady of the male fifth leg and the currently reported genetic data lead us to conclude that C. natalis is distributed from the Bay of Biscay southwards along the eastern Atlantic, around the Cape of Good Hope, and northwards along the western boundary of the Indian Ocean as far as the Arabian Sea. A by-product of this study is the recognition that Calanoides macrocarinatus is a junior synonym of Calanoides brevicornis. Females of C. natalis are easy to distinguish morphologically from C. carinatus s.s. but are more similar to C. brevicornis, apart from size differences. From physical oceanographic evidence we conclude that the Indian Ocean is currently the upstream part of the distribution of C. natalis. Calanoides philippinensis is known to extend into the eastern Indian Ocean at tropical latitudes. It is not known if it is C. philippinensis that has been recorded along the western coast of Australia. An apparently undescribed species of Calanoides occurs on the eastern Australian coast.     

Structure of the reproductive system and hectocotylus in males of lesser flying squid Todaropsis eblanae (Cephalopoda: Ommastrephidae)

This paper introduces new data on Todaropsis eblanae morphology, morphometry and functional aspects of the male reproductive system and hectocotylus. Spermatophores differ in specimens from the Atlantic Ocean (average length, 18.28 ± 1.45 mm, 15.63 ± 0.8% of mantle length; weight, 2.0–12.0 mg) and the Indian Ocean (average length, 24.8 ± 2.85 mm, 16.9 ± 2.1% of mantle length; weight, 35.0–39.6 mg) (t?=?3.14; p < 0.01 for absolute sizes and t?=?0.711; p > 001 for relative sizes). An additional important distinctive trait is the form of connection of the cement body with the ejaculatory tube. In recent years, T. eblanae has been regularly caught in the Barents Sea, meaning its range has extended to subarctic waters. The morphology and morphometry of the spermatophoric complex of organs did not vary in investigated parts of its range. Hectocotylus patterns and some important spermatophore traits distinguish Todaropsis from other Ommastrephidae.     

Taxonomy and distribution of ariid catfishes from the Arabian Gulf

Four morphologically distinct species of ariid catfish are found in northern regions of the Arabian Gulf, Arius thalassinus, A. dussumieri, A. tenuispinis and A. bilineatus, the latter having been frequently confused with and reported as A. thalassinus in earlier studies. An index of simple observations and measurements based on tooth patch structure and body dimensions was devised to distinguish between the four species. The recognition of A. tenuispinis and A. dussumieri in the Arabian Gulf greatly extends their reported distribution ranges.     

Records of ascidians from Bahrain,Arabian Gulf with three new species

Fifteen ascidian species were identified from 1 to 12 m depth in coastal waters of Bahrain, Arabian Gulf. Three new species, Aplidium rubripunctum, Didemnum yolky and Symplegma bahraini are described. Four species collected are cosmopolitan. This study increases knowledge of the ascidian fauna of an area for which only sporadic collections have previously been made.     

Shallow-water Mysida (Crustacea: Mysidacea) of Bahrain (Arabian Gulf): species composition,abundance and life history characteristics of selected species

Mysida were collected from Tubli Bay and the eastern coastline of Bahrain during 1991–1992 incidental to a survey of penaeid prawns. These samples provided an opportunity to assess the species composition of mysids from a nearshore region of the Arabian Gulf—an area in which mysid fauna is poorly known. The 114 beam trawl samples yielded >29?000 mysids. Rhopalophthalmus sp. (>90%), Siriella brevicaudata (5%), Kainomatomysis foxi (1.2%), Siriella sp. A (0.9%) and Indomysis annandalei (0.6%) were the most abundant of 11 species identified. Basic life history variables (carapace length, life stage, brood size) were measured for these five taxa.     

Nesomyrmex micheleae,a new ant species (Hymenoptera: Formicidae) from the Dhofar Governorate,Oman, with a synoptic list,distribution map and key to the Arabian Nesomyrmex

ABSTRACT

A new species of the myrmicine ant genus Nesomyrmex Wheeler, 1910, N. micheleae Sharaf sp. nov., is described and illustrated from Oman based on the worker caste. The new species is a member of the N. angulatus species group and can be diagnosed by the golden yellow gaster that contrasts with the dark brown body; the irregular longitudinal rugulose sculpture on the cephalic surface; and the finely punctate mesonotum and propodeal dorsum. A synoptic species list, an updated key and a distribution map to the Arabian Nesomyrmex species are presented. Continued ant species discoveries are central to large-scale diversity patterns, conservation biology and macroecology.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:FBCEACA7-E543-4B10-AB9D-D63319DCB31F http://www.zoobank.org/urn:lsid:zoobank.org:act:1D2EC498-3B2E-43CD-A3C0-1C6C237471E2     

Anomuran Crustacea (Paguridea,Porcellanidae, and Hippidea) from Oman,principally from Dhofar province,southern Oman

Anomura (Crustacea, Decapoda) are described from 5 collection sites in Dhofar (southern Oman) and from near Muscat (northern Oman). These consist of the following: Paguridea: Aniculus erythraeus, Calcinus (3 species), Cestopagurus coutieri, Clibanarius (3 species), Dardanus (5 species), Diogenes (2 species), Paguristes (2 species) and Coenobita scaevola; Porcellanidae: Pachycheles (2 species), Petrolisthes (7 species), Pisidia (3 species) and Polyonyx (1 species, probably undescribed); and Hippidea: Emerita holthuisi, Hippa pacifica and Albunea steinitzi. The anomuran fauna of the region is not well known, and that of Dhofar has not previously been investigated. The present records establish a number of significant range extensions. The anomura species composition of Dhofar is discussed in relation to that of other areas of the Indian Ocean. In general, pagurideans appear less cosmopolitan, and more parochial within the region than porcellanids. This is discussed in relation to larval dispersal and other factors.     

On the fly fauna of the central region of the Kingdom of Saudi Arabia: new country records from Riyadh Region,with a list of associated fly species and zoogeographical remarks (Insecta: Diptera)

This study presents three genera and 10 species of flies (order: Diptera) as new country records from the Kingdom of Saudi Arabia (KSA). The flies were identified from Rawdhat Khorim National Park in Riyadh Region, the central region of KSA. The newly recorded genera are Glabellula (Mythicomyiidae), Phora (Phoridae) and Ceroptera (Sphaeroceridae), and the newly recorded species are Dilophus lingens (Bibionidae), Stichopogon deserti (Asilidae), Glabellula sp. (Mythicomyiidae), Phora sp. (Phoridae), Liriomyza lutea (Agromyzidae), Ceroptera aharonii (Sphaeroceridae), Trixoscelis deemingi, Trixoscelis migueli and Trixoscelis puncticornis (Trixoscelididae), and Physiphora leucotricha (Ulidiidae). Glabellula sp. and Phora sp. have been identified only to the genus level and are listed herein only because this is the first time they have been recorded in KSA, and additional specimens are required for their accurate identification to the species level. Also, this is the first record of Trixoscelis deemingi Wo?nica and Trixoscelis migueli Wo?nica from the Palaearctic Region. Distribution, diagnoses, remarks on biology and coloured photos are given for the recorded taxa. A list of associated fly species that were previously recorded in KSA and are identified from the study area in the present study is also presented. Zoogeographically, 33% of the identified fly species showed both Afrotropical and Palaearctic affinities, while 17% were of only Palaearctic affinity, and 8% were of only Afrotropical affinity. Elements from other regions were apparently nil. The results support the idea that the central Arabian Desert, which includes the present study area, is a transitional zone between the Palaearctic and Afrotropical regions.     

First records of dendrobranchiate prawns (Decapoda: Dendrobranchiata) from the Andaman Sea,India

ABSTRACT

The Andaman Sea adjoining the Indian Territory is biologically rich in terms of marine diversity. However, inadequate surveys during the post-independence era have resulted in large lacunae in data on the species composition in these waters. In this paper, we report the first observation of two species of dendrobranchiate prawns, Metapenaeopsis difficilis Crosnier, 1991 and Haliporus taprobanensis Alcock and Anderson, 1899, in the Indian seas, supplemented with notes on their morphological diagnoses, comparison with closely related species and zoogeographical distribution. Crustacean specimens were collected using trawl nets and a naturalists’ dredge on board the Fisheries Oceanography Research Vessel Sagar Sampada in the deeper offshore region between 124 and 850 m depth in the Andaman Sea during the period 2015–2017. Metapenaeopsis difficilis is distinguished by an oval-shaped thelycal plate and a low, unarmed bead-like plate on the thoracic sternum between the third pereiopods. Metapenaeopsis difficilis is previously reported from the Philippines, Indonesia, Coral Sea, New Caledonia, Marquesas Islands, and Wallis and Futuna Islands at depths between 21 and 440 m, thereby indicating its westward range extension. Haliporus taprobanensis is distinguished by a tough integument, presence of a postero-dorsal spine on the fourth pleonal somite, and smooth dorsum of the first four pleonal somites. Haliporus taprobanensis is previously reported from South Africa, Madagascar, off Sri Lanka, Indonesia, Philippines and northern Australia at depths between 300 and 1650 m.     

A new Arietellidae (Copepoda: Calanoida) from the Red Sea

A new species of the calanoid copepod genus Paramisophria T. Scott, 1897 is described from the Egyptian sublittoral zone of the Red Sea. Paramisophria aegypti sp. nov. appears to be closely related to the species Paramisophria ammophila and Paramisophria platysoma. Paramisophria aegypti differs from P. ammophila in having two unequal lateral setae plus one long terminal process and two tiny equal lateral setae plus one long terminal process on the third exopodal segment on the male right and left fifth legs (vs three terminal processes increasing in size inward on both male fifth legs). Paramisophria aegypti can be distinguished from P. platysoma in the following characters: prosome symmetrical (vs extreme asymmetry); third exopod segment of the right leg completely separated from the second segment and bears two unequal lateral setae plus one long terminal process (vs partially fused to the second segment and bears four terminal processes increasing in size inward); third exopod segment of the left leg with two lateral setules and one long terminal process (vs two lateral setules, one short outer medial process and one long terminal process); endopodal lobes of the female legs 5 bear one long plumose seta (vs setae are lacking).http://www.zoobank.org/urn:lsid:zoobank.org:pub:C0A92BF9-2306-4A35-AA39-CE3B5865A396     

Sillago suezensis,a new whiting from the northern Red Sea,and status of Sillago erythraea Cuvier (Teleostei: Sillaginidae)

The status of Sillago erythraea Cuvier in Cuvier and Valenciennes 1829 is re-examined. A lectotype designation by McKay in 1985 fixes it as a junior synonym of Sillago sihama (Forsskål in Niebuhr, 1775), which is restricted to the southern Red Sea. Northern Red Sea populations previously assigned to S. sihama or S. erythraea, are here described as Sillago suezensis sp. nov. Sillago suezensis is also distributed in the eastern Mediterranean Sea due to Lessepsian immigration through the Suez Canal. The new species is characterized within the Sillago sihama group, which has the swimbladder divided posteriorly into two tapering extensions projecting below the vertebral column extending into the tail musculature, by the absence of scales on the preopercle and on most of the opercle, a total number of 34 vertebrae, the swimbladder with lateral extensions each spreading a blind tubule anterolaterally, and a low position of the nostril.

http://www.zoobank.org/urn:lsid:zoobank.org:act:B289CDF4-AE82-44D3-9AE1-4A2B514AD348     

A redescription of the fossil coleoid cephalopod genus Palaeololigo Naef, 1921 (Decapodiformes: Palaeololiginidae) and its relationship to Recent squids

Neocoleoid cephalopods are poorly represented in the fossil record and fossils which can be confidently aligned with extant species are very scarce. The rare Solnhofen genus Palaeololigo is an exception to this, showing marked resemblance to Recent squids. Naef misinterpreted the structure of the fossilized gladius of Palaeololigo and the present study redescribes the genus. The gladius and fossilized fin impressions of Palaeololigo closely resemble that of the extant decapodiform squid genera Bathyteuthis and Chtenopteryx (Superfamily Bathyteuthoidea). The possible relationship between Palaeololigo and the bathyteuthoids and their position in decapodiform phylogenetics is discussed.     

Two new species of Enoplida (Nematoda) from the Yellow Sea,China

Two new species of free‐living marine nematodes Adoncholaimus chinensis sp. nov. and Bathylaimus huanghaiensis sp. nov. from the Yellow Sea, China are described and illustrated. Adoncholaimus chinensis sp. nov. is characterized by the gubernaculum with a slender apophysis; two files of seven to eight circumcloacal setae on each subventral side of body. Bathylaimus huanghaiensis sp. nov. is characterized by a cylindrical body and smooth cutical. The buccal cavity is relatively smaller than in other species of the genus Bathylaimus. The anterior buccal cavity has only one obvious dorsal tooth. The amphids are subspiral with 1.2 turns, posterior to the base of posterior buccal cavity. They also have a long three‐jointed cephalic seta.     

A new species of Didogobius (Teleostei: Gobiidae) from the Adriatic Sea

Didogobius schlieweni sp. nov. is described from a single specimen collected among pebbles in shallow water at Unije island, near Cres, in the northern Adriatic Sea. The holotype has vivid dark and pale patterning, and is assigned to Didogobius on the basis of head neuromast patterns and meristic features. Diagnostic values of the latter are D2 I/12, A I/11, P 17, and LL 55–56. A key to species of the Chromogobius and Didogobius complex is provided.     

Effect of tropical monsoon on fishery abundance of Indian squid (Uroteuthis (Photololigo) duvaucelii)

Indian squid, Uroteuthis (Photololigo) duvaucelii (Loliginidae) constitute an important component of the inshore cephalopod fisheries along the eastern Arabian Sea. Local environmental variation plays an important role in species–environment interactions in neritic squids, which inhabit nearshore/coastal waters. Such ‘active’ and ‘passive’ responses of squids to environmental changes is crucial in understanding their relationships and influence on the biological processes, distribution and abundance of the fast-growing short-lived coastal loliginids. The empirical relationship between squid abundance and the variability in rainfall and sea surface temperature (SST) were explored in a tropical monsoon fishery. Monthly catch rates (catch per fishing hour) of squids in commercial trawl during 1987–2009 were used as the abundance index. Linear regression models with ARIMA errors were fitted with catch per unit hour time series as dependent variable and rainfall and SST as exogenous variables. While rainfall was observed to have a negative effect on squid abundance, the SST recorded a positive impact. ARIMA models provided satisfactory fit to observed data and forecast of 22 months. Given that the squid life-cycle is a function of their environment, this result is relevant in forecasting squid biomass for the management of tropical monsoon fisheries.     

A new genus of Cletodidae (Copepoda; Harpacticoida) from the Bohai Sea,China

Neoacrenhydrosoma zhangi gen. et sp. nov. is described from specimens recovered from muddy sediments in the shallow waters of the Bohai Sea. On the basis of the structure of the mouthparts, P5 of both sexes and the female genital field, it is suggested that the taxon is related to the Acrenhydrosoma-complex within the Cletodidae. It differs from other known genera in the structure of the exopod in P2–P4 which is two-segmented as a result of the failure to separate the proximal two segments of a three-segmented ramus; and the P5 in as much as the mucroniform process incorporates the exopod, as well as the endopodal lobe of the baseoendopod.     

Three new species of the genus Belbolla (Nematoda: Enoplida: Enchelidiidae) from the Yellow Sea,China

Three new species of free‐living marine nematodes of the genus Belbolla: Belbolla huanghaiensis sp. nov., Belbolla stenocephalum sp. nov. and Belbolla warwicki sp. nov. from the Yellow Sea, China, are described and illustrated. Belbolla huanghaiensis can be separated from other species in the Belbolla genus by the number of oesophageal bulbs (nine), the length of the spicules and gubernacular apophysis, and the size of the two winged precloacal supplements. Belbolla stenocephalum can be separated from other species by the number of oesophageal bulbs (eight), the length of the spicules and the structure of gubernacular apophysis. Belbolla warwicki sp. nov. is characterized by the number of oesophageal bulbs (seven), reduced precloacal supplements and the structure of gubernacular apophysis. A key to the genus Belbolla is provided to facilitate species identification. Types are deposited in the College of Life Science and Technology, Ocean University of China.     

Marine biodiversity on the Algerian Continental Shelf (Mediterranean Sea)

The Mediterranean Sea is known as a biodiversity hot spot, with 16,848 species reported. Biodiversity is higher in coastal areas and decreases with depth. However, knowledge about the southwestern sector remains scarce. For the last three decades, sampling of soft-bottom communities along the 1180 km of the shallow Algerian coast (0–136 m) has recorded 1642 macrobenthic species. There is a decreasing west–east species-richness gradient, especially for the total species richness and the amphipods. In addition, quantitative sampling in Bou Ismail Bay in summer 1988 (98 sampling sites for a total of 841 species) shows that diversity indices (i.e. species richness, >100 species for 0.2 m^?2; Shannon diversity, >6.0; and ES₅₀, >34) are among the highest for similar sand and muddy-fine sand communities in the Mediterranean Sea and the northeastern Atlantic Ocean. Bou Ismail Bay appears to have the highest species richness among Algerian bays, probably because of its variety of benthic habitats and the absence of significant pollution in this area. Monitoring must be undertaken to survey this high biodiversity, and a national strategy should be proposed to preserve high diversity zones.