Two obligate cave-dwelling species of cyclopoid copepods (Copepoda, Cyclopoida) were discovered inside caves in central Thailand. Siamcyclops cavernicolus gen. et sp. nov. was recognised as a member ...of a new genus. It resembles Bryocyclops jankowskajae Monchenko, 1972 from Uzbekistan (part of the former USSR). It differs from it by (1) lack of pointed triangular prominences on the intercoxal sclerite of the fourth swimming leg, (2) mandibular palp with three setae, (3) spine and setal formulae of swimming legs 3.3.3.2 and 5.5.5.5, respectively, and (4) specific shape of spermatophore. Metacyclops thailandicus sp. nov. resembles M. cushae Reid, 1991 from Louisiana (USA). It differs from it by (1) distal segment of the endopod of the fourth swimming leg with one apical spine, (2) the fifth swimming legs with one broad segment, (3) the spine formula of the distal segment of the exopod of the swimming legs 3.4.3.3, and (4) well developed anal operculum reaching articulation with caudal rami. Detailed descriptions of the habitats of the new species and up-to-date keys to the genera and subgenera of the Bryocyclops and Microcyclops groups are provided, along with an updated list of obligate groundwater species of Copepoda in Southeast Asia.
More accurate interpretations are required in order to understand the processes of hydrological movement and hydrochemical variation of water flow in epikarst. A drip VP1 from the Velika Pasica Cave ...(Central Slovenia) was studied during a period which occurred at the end of a long wet, cold winter. The sources of the percolation water in the cave were both from rain water and snowmelt water. The discharge was continuously monitored during study period in one hour intervals. Each hour a water sample from the drip was taken for measurements of pH, electric conductivity and major ions concentrations. Because of the specific climatic condition in the shallow cave, the dilution effect is the dominant mechanism in the hydrochemical processes, determining drip water properties. The effect of CO2 corrosion and prior calcite precipitation (PCP) was weakened with that condition; Mg2+ varied slightly more significantly than Ca2+, which was reflected by the high correlation between Mg2+, Ca2+ and micro-variation of Mg/Ca ratio. The variation of pH followed closely to the changes of other parameters, which is rarely noted in other works.
Between 4th and 18th March 2014, an international group of biologists carried out a hydrobiological expedition to the Ounianga-Tibesti area of northern Chad (Africa). The Tibesti is a desert volcanic ...area, intersected by the beds of ancient rivers which were active in the Tertiary. In deep canyons there are small water bodies (gueltas/aguelmans), fed by rain and spring water. They are rich in zooplankton, benthos, and even fish, but their groundwater fauna has previously been unknown. Groundwater samples collected in the vicinity of one guelta contained Syncarida, Isopoda, and Copepoda. Among the latter, two new species were recognised, Haplocyclops (H.) henrii sp. nov. and Parastenocaris joi sp. nov., together with a third species, Pilocamptus schroederi (van Douwe, 1915), previously known only from the littoral zone and wet mosses of Lake Victoria. The Tibesti area is thus the third known location of P. schroederi. All these species have a Gondwanaland distribution and are probably relicts of the Tertiary fauna, formerly widespread in the Sahara. Together with descriptions of two new species, a detailed re-description of P. schroederi is presented, along with remarks on their ecology.
Microcrustacean (Copepoda, Ostracoda) assemblages were investigated at the interface of the vadose and phreatic zones in the alpine karstic aquifer from the Julian Alps in Slovenia (SE Europe). Two ...temporary and one perennial karstic outlets were sampled by filtering the water several times over 2 years. Concurrently, benthos from the mouth of a perennial spring and from an adjacent spring brook were collected. Altogether 24 microcrustacean species were recorded. The spatial and temporal variation in drift densities and species composition was high indicating complex groundwater hydrological pathways being dependent on precipitation regime. Non-metric Multidimensional Scaling (NMDS) clearly separated drift samples from temporary springs and other sample groups (drift in perennial spring, spring mouth and spring brook benthos). ANOSIM revealed statistically significant differences between all sample groups (Diacydops zschokkei, Elaphoidella phreatica and Mixtacandona sp. B contributed over 50 % to the observed differences among sample groups. Three species (Nitocrella sp., Speocydops internus, Lessinocamptus pivai), known to be typical epikarst species, were collected only in the drift from one temporary spring (T2). Mao Tau species accumulation curves did not reach asymptote for the drift from temporary springs, but did for the drift from perennial spring, and for the spring mouth and the spring brook benthos. The results on drift composition indicated the variation in the origin of the water discharging at the interface ofvadoze and phreatic zones depending greatly on water level conditions, while the drift densities were higher in the water presumably discharging from phreatic zone (perennial spring and temporary springs during low water levels).
We describe two new species of the genus Fierscyclops Karanovic, 2004, F. tanaosriensis n. sp. and F. solaris n. sp. from western Thailand, which are also the first records of this genus in Southeast ...(SE) Asia (and also Asia). The two new species share several characters such as: i) presence of lateral sensillum on the caudal ramus in both females and males; ii) one-segmented swimming leg 5 (P5) inserted on the lateral corner of the thoracic somite 5; iii) free segment of P5 with two elements (spine and seta), apical inner spine is robust, insertion distance between the apical spine and apical seta is relatively large; iv) swimming legs 1-4 (P1-P4) rami are two-segmented; v) distal segment of endopod (Endp2) of P4 has two apical spines; vi) spine and seta formula of distal segment of exopod (Exp2) of P1-P4 are 3.4.4.3 and 5.5.5.5, respectively; vii) coxobasis and Endp2 of the antenna have two and 10 setae, respectively. The two new species differ from the Australian type-species of the genus F. fiersi (De Laurentiis, Pesce & Humphreys, 2001) in: i) setation of the antenna; ii) longer inner apical spine on P5; iii) relatively longer genital double-somite in female; iv) relatively shorter caudal rami; v) presence of lateral sensillum on the caudal ramus in both females and males. The Thai species differ from one another in: i) ornamentation of the body integument; ii) shape of the posterior margin of the thoracic somite 2; iii) spinule ornamentation of the syncoxa of the maxilliped; iv) shape of the medial expansion of P2-P4 basis in females.
The unsaturated zone in fissured (= karstic) aquifers continues to be a source of new species of Harpacticoida (Crustacea: Copepoda). The first species were discovered about 70 years ago in the ...Škocjanske Jame Cave in Slovenia. Intensive sampling of percolating water in caves there over the last 20 years has yielded several new species, some of them well adapted to that environment. The most recent studies revealed that such a specialised fauna is also present in other regions of Europe, South and North America, and Asia. In Europe, three genera belonging to the order Harpacticoida are characteristic of the unsaturated karstic zone: Morariopsis, Paramorariopsis and Elaphoidella. In this article, two highly specialised species of Elaphoidella are described. A detailed analysis of their ecology and morphological adaptations along with other species of the genus Elaphoidella from Slovenia is included, and comparisons are made with the epikarstic genera Morariopsis and Paramorariopsis.
Two new species of copepods of the genus Elaphoidella Chappuis, 1929 were discovered in a cave and a spring in northeastern Thailand. The first species, E. phuphamanensis sp. nov., belongs to ...species-group VII sensu Lang. It is most similar to E. turgisetosa Petkovski, 1980 in the armament of the male third exopod of the fourth swimming leg and the shape and armament of the fifth swimming leg in both sexes. However, it is easily distinguished from other congeners by the segmentation of the first swimming leg, the endopod of the fourth swimming leg, and the armature of the third exopod of swimming legs 2–4 in both sexes. The second species, E. propecabezasi sp. nov., is located in species-group I sensu Lang, where the male does not have a transformed seta on the third exopod of the fourth swimming leg and the female fifth swimming leg has four baseoendopodal robust setae, unequal in length. It is most similar to E. cabezasi Petkovski, 1982 and E. paraaffinis Watiroyram, Sanoamuang and Brancelj, 2017 in having the same armature formula as endopods 1–2 of female swimming legs 1–4. However, the ornamentation of the anal operculum, the shape of the caudal ramus, and the armature of the fifth swimming leg in both sexes distinguish them from each other. A rare gynandromorphic specimen of E. propecabezasi sp. nov. was recorded, and a revised key to Elaphoidella species in Southeast Asia is provided.
Harpacticoids are an important component of meiofaunal assemblages in hyporheic zone. The goal of this study was to investigate distribution patterns of interstitial harpacticoid assemblages from ...four pre-Alpine streams originating in the Dinaric Karst and flowing into the Ljubljanica River. The sampling was conducted in 2002 at 12 locations distributed at a distance of approximately 1 km along each stream including tributaries, at a depth of 30–60 cm in the wetted channel (three sites per location) and depths from 65 to 160 cm on the stream banks (one site per location) using a Bou-Rouch pump. Concurrently, the interstitial water’s physical and chemical parameters were measured at two sites within each location (streambed, streambank). A total of 24 harpacticoid species were found, 12 of which were stygobionts (i.e., species living exclusively in groundwaters). Among them, two previously unknown species for science were found. Harpacticoid assemblage composition, with the exception of those from the Iška stream, did not differ significantly between the streams, indicating interconnectivity of the interstitial milieu. Sediment structure, amounts of particulate organic matter, conductivity and redox conditions seemed to have certain impacts, indicating the importance of hydrological and geological settings for harpacticoid assemblages.
Groundwater fauna consists of organisms that are adapted to live their whole life-time in different types of groundwater (=aquifers): with fissured (karstic) and porous (alluvium) types as the most ...common. About 3800 species of obligate groundwater species (stygobionts) have been recorded worldwide and 2000 of them from groundwater in Europe. Before 1970, 19 species of stygobionts were known from Southeast Asia. After 1980, the number of stygobionts from this region started to increase, and, at present, 122 stygobionts are known here. Most of them are crustaceans, with the Copepoda, Isopoda, Amphipoda and Decapoda as the most abundant groups. Intensification of research on groundwater fauna can considerably increase the total number of stygobionts known from the region, which could rises up to several times the current tally if the intensity of research was comparable with that in Europe.
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