A taxonomic review of the coastal genus Iotarphia Cameron (Coleoptera: Staphylinidae: Aleocharinae) with a description of new species based on morphological and molecular characters

A taxonomic review of the marine littoral genus Iotarphia Cameron is presented. Three species are recognized, one of which is described as a new species (I. magna Song & Ahn, sp. n.) based on morphological and molecular characters. Genetic divergence of COI using uncorrected p-distance among Iotarphia species ranged from 10% to 11.6%, while intraspecific divergence ranged from 0% to 1.3%. All three species were strongly supported as a single lineage on both neighbor-joining and parsimony trees. The genus Iotarphia and I. australis Cameron are redescribed with illustrations of diagnostic characters. The female of I. rufobrunnea is characterized for the first time. A key and comparison table for similarities and differences among the species are presented.

Caspian cyanobacteria of Azerbaijan: a complete checklist with ecological and geographical characteristics

The article presents the results of a taxonomic revision of the species diversity of cyanobacteria in the Azerbaijani sector of the Caspian Sea according to literature and original data. For the period from 1870 to 2019, 98 species from 44 genera of Cyanophyceae were found off the Caspian coast of Azerbaijan. Phormidium Kützing ex Gomont, Chroococcus Nägeli, Lyngbya C. Agardh ex Gomont, Oscillatoria Vaucher ex Gomont, Merismopedia F.J.F.Meyen and Spirulina Turpin ex Gomont lead in species number. 64 species from 32 genera were found in both plankton and benthos. 33 species from 20 genera of cyanobacteria were common for these communities. Off the coast of Azerbaijan, 64.7% of the genera and 48.0% of the species of сyanobacteria known for the Caspian Sea as a whole have been identified, which indicates that the marine cyanoflora of Azerbaijan has been studied quite fully. The analysis of ecological and biogeographic features of the identified species is given. Among the cyanobacteria of the Azerbaijani coast, the inhabitants of fresh waters are the most numerous (39.2%), followed by freshwater/brackish and brackish species (35.1% together), marine species are the third (16.5%). The predominance of freshwater and brackish forms reflects the specificity of the Caspian Sea as a closed water body with a lower salinity in comparison with oceanic waters. By ecotopic confinement, most of the species found are known as benthic (62.9%), the proportion of truly planktonic species is 29.9%. At the same time, film-forming species are widely represented not only in benthic communities (82.8%), but also in the water column, where they account for about half of the identified species (48.5%). This is related to the hydrological features of coastal ecotopes, where the surf-wave impact on the marine littoral contributes to the penetration of bottom filaments into the water column. The geographical spectrum is characterized by the predominance of species with a cosmopolitan (45.4%) and sub-cosmopolitan (30.9%) distribution, which reflects the tense ecological situation in the region.

Phototrophic biofilms and microbial mats from the marine littoral of the central Mediterranean

Phototrophic biofilm and microbial mat communities grow along the rocky coastline of the Maltese islands. During this study, phototrophs from the mediolittoral and supralittoral zones were studied over a two-year period and seasonal changes were observed. Attachment of pioneer microorganisms to the porous eroded limestone bedrock was facilitated via a gelatinous matrix composed of exopolymeric substances (EPS). In submerged areas, such as undisturbed rock pools, these progressively formed green or brown compact biofilms, some of which thickened over spring to form microbial mats via the production of more extensive EPS layers. Microbial mats gradually attained a lighter colouration due to the presence of ultraviolet (UV) screening pigments. In full summer, they were observed to shrink, detach from the exposed substrate, harden and progressively calcify. Biofilm microorganisms survived the harsh summer months in sheltered areas. The major biofilm formers were filamentous non-heterocytous cyanobacteria belonging to the Leptolyngbyaceae, Pseudanabaenaceae and Oscillatoriaceae. Their sheaths were thick, lamellated and often confluent. A higher biodiversity of phototrophs was observed in late autumn and winter, when tufts of heterocytous Calothrix sp. grew on thin compact biofilms of Nodosilinea sp., Toxifilum sp. and Phormidesmis spp., while Lyngbya spp. trichomes were surrounded by thick brown sheaths. Germlings of green and brown macroalgal species belonging to Ulva, Cladophora and Sphacelaria were embedded in biofilms and microbial mats and gradually grew to form extensive macroalgal covers submerged in rock pools. Erythrotrichia sp. filaments colonised the mediolittoral zone and were confined to areas that were exposed to wave action and submerged intermittently. Over summer, macroalgal coverage diminished and microalgal biofilms and microbial mats prevailed in rock pools.

Description of the adult and larva of Clunio balticus Heimbach, 1978 (Diptera, Chironomidae) from the seashore of Bergen (Norway)

The male and female adult and larva of Clunio balticus Heimbach, 1978 are diagnosed and described based on reared material, which was collected in the marine littoral zone along the coast of Bergen (Norway). Male and female adults and larvae of C. balticus can be easily distinguished from other known European Clunio species on the basis of some atypical features found in the male and female adults and fourth instar larvae. The biological cycle (reproduction and emergence) of C. balticus is a slight semilunar-periodic synchronization on days near the high tides. C. balticus is a local biogeographic representative of the northern Atlantic coast, which includes the eastern and western seashores. Remarks on related known Clunio species from Europe with comments on the ecology and geographical distribution of C. balticus are given.

New records of Collembola from marine littoral sand of Hainan Island, China, with description of a new Oudemansia species (Neanuridae: Pseudachorutinae)

One new species of springtail, Oudemansia chenorum sp. nov., is described and illustrated. Pseudanurida sawayai Schuster, 1965 is reported from Hainan Island for the first time. An identification key for the species of Oudemansia Schött, 1893 is provided and remarks are made on its peculiar morphology as well as that of close related genera. The presence of pseudocelli is further confirmed on members of the genus Oudemansia.

A remarkable new genus and species of Hansenauropodidae (Myriapoda, Pauropoda) from the seashore of Hainan Island, China

Psammopauropus macrospinus gen. et sp. n., a remarkable new genus and species of the pauropod family Hansenauropodidae is described from the marine littoral habitat of Hainan Island, South China. It has one pair of dorsal spines on the pygidium differentiated from seta a1, large globular seta st on pygidium, and globular distal setae on the tarsi by which Psammopauropus can be easily distinguished from all other genera of the family. In addition, the adaptive characters of the littoral pauropods are preliminary discussed. This is the first record of the family Hansenauropodidae from China.

Chironomidae (Diptera) of Croatia with notes on the diversity and distribution in various habitat types

The family of non-biting midges (Diptera, Chironomidae) represent one of the most common and abundant group in freshwaters, inhabiting a wide variety of habitats and ecological niches. Although there is a long tradition of limnological research in Croatia, to date no extensive species list has been made for this insect family. Thus, we summarized the results of our research and reviewed published data on chironomid fauna of Croatia in various freshwater habitat types, including extreme ones, such as caves, peatbogs or marine littoral. A total of 239 species were recorded representing five subfamilies: Chironominae (125 species) Orthocladiinae (83 species), Tanypodinae (23 species), Diamesinae (6 species) and Prodiamesinae (2 species). The most frequent species were Cricotopus bicinctus, Dicrotendipes nervosus, Synorthocladius semivirens, each found in more than 20% of the studied localities. Ablabesmyia monilis and Procladius choreus represented the most frequent Tanypodinae species, recorded in more than 12% and 17% of the sites, respectively. The research of chironomid ecology, diversity and distribution continues, which will provide new data and information, but this first comprehensive checklist provides a good starting point for those studying Chironomidae or other freshwater Diptera, in Croatia and Europe.

Aerial and aquatic respiration in littoral Oniscidea (Isopoda) from Southern California, USA

The large radiation of terrestrial isopods (suborder Oniscidea) includes several families that are represented primarily in marine-littoral or riparian habitats. Among these are members of Ligiidae and Tylidae as well as several basal families within the section Crinocheta. Structural and physiological evidence supports a marine-littoral ancestry of the Oniscidea. We examined aerial and aquatic respiration (measured as VCO2) in six species of marine-littoral Oniscidea representing five families, as well as one riparian and one endogean species. Complimentary data were collected for immersion tolerance and whole-animal permeability in air, and structural specialization of the respiratory pleopods was examined using SEM. Ligia occidentalis Dana, 1853 (marine, littoral) and Ligidium lapetum Mulaik & Mulaik, 1942 (riparian) showed similar VCO2 in air and water. VCO2 in air for the other species was significantly higher than in water. Compared across species, aerial VCO2 scaled with mass in accordance with Kleiber’s law (β = 0.774) while aquatic VCO2 increased in approximate proportion to mass (β = 0.957). At least some specimens of the six marine-littoral species survived over 24 h immersion. Ligidium lapetum and the endogean trichoniscid Brackenridgia heroldi (Arcangeli, 1932) also tolerated prolonged immersion in freshwater but did not survive beyond 5–6 h, probably due to limited capacity for hyper-regulation. The upper shore sand-burrowers, Tylos punctatus Holmes & Gay, 1909 and Alloniscus perconvexus Dana, 1856 had the lowest permeability among the study species and are the only representatives with elaborated pleopodal respiratory fields (Alloniscus) and lungs (Tylos). The ventral lung spiracles of T. punctatus are surrounded by an extensive cuticle meshwork and we propose that this functions as a plastron field to enhance aquatic gas exchange. Collectively, the results show that littoral species tolerate significant periods of immersion, allowing them to withstand habitat inundation during spring high tides, storm swells and, in riparian species, rainstorms and snowmelt.

Description of the adult and immature stages of Clunio ponticus Michailova, 1980 (Diptera, Chironomidae), from the Black Sea, Varna, Bulgaria

The mature and immature stages of Clunio ponticus Michailova, 1980 are diagnosed and described based on associated material recently collected in the marine littoral zone of Varna, St-Konstantin and Helena Resorts, Black Sea (eastern Bulgaria). Male and female adults, pupae and larvae of C. ponticus can be easily distinguished from other known European Clunio species on the basis of some atypical features found in the male and female adults, pupal exuviae and fourth instar larvae. In addition, the biological cycle (reproduction and emergence) of C. ponticus is not synchronized with lunar periodicity (new and full moon) as for some other known Clunio species from Europe, but closely related to the typology of the intertidal zone along the coastline of the Black Sea. This indicates that this species is a local biogeographic representative of the ‘Pontus Region’, which includes the eastern coastline of the Black Sea. Remarks on related known Clunio species from Europe with comments on the ecology and geographical distribution of C. ponticus are given.