Growth and population biology of the sand-bubbler crab Scopimera crabricauda Alcock 1900 (Brachyura: Dotillidae) from the Persian Gulf, Iran

Background Dotillid crabs are introduced as one common dwellers of sandy shores. We studied the ecology and growth of the sand bubbler crab Scopimera crabricauda Alcock, 1900, in the Persian Gulf, Iran. Crabs were sampled monthly by excavating nine quadrats at three intertidal levels during spring low tides from January 2016 to January 2017. Results Population data show unimodal size-frequency distributions in both sexes. The Von Bertalanffy function was calculated at CWt = 8.76 [1 − exp (− 0.56 (t + 0.39))], CWt = 7.90 [1 − exp (− 0.59 (t + 0.40))] and CWt = 9.35 [1 − exp (− 0.57 (t + 0.41))] for males, females, and both sexes, respectively. The life span appeared to be 5.35, 5.07, and 5.26 years for males, females, and both sexes, respectively. The cohorts were identified as two age continuous groups, with the mean model carapace width 5.39 and 7.11 mm for both sexes. The natural mortality (M) coefficients stood at 1.72 for males, 1.83 for females, and 1.76 years−1 for both sexes, respectively. The overall sex ratio (1:0.4) was significantly different from the expected 1:1 proportion with male-biased. Recruitment occurred with the highest number of annual pulse once a year during the summer. Conclusions The results, which show slow growth, emphasize the necessity of proper management for the survival of the stock of S. crabricauda on the Iranian coast of the Persian Gulf.

Tigriopus iranicus sp. nov., a new species of Harpacticidae (Copepoda, Crustacea) from Iran, with a redescription of T. raki Bradford, 1967

The first representative of Tigriopus Norman, 1869 from the north-western Indian Ocean is described from rock pools on the Iranian coast. Tigriopus iranicussp. nov. is distinguishable from its congeners by i) the possession of two maxillary endites, each with two setae; ii) a two-segmented mandibular endopod; iii) P1enp-3 with one pinnate claw, a well-developed geniculate spine and a small seta; and iv) female P6 with two setae. Additionally, we present a complete redescription of Tigriopus raki Bradford, 1967 on the basis of paratype material and a key to the species of the genus.

HEAVY PRECIPITATION ON THE IRANIAN COAST OF THE CASPIAN SEA

The main goal of this research is to determine the genesis of heavy precipitation on the Iranian coast of the Caspian Sea, to quantify the contribution of various factors to the formation of such precipitation. An analysis of synoptic fields, satellite data and the results of numerical mesoscale modeling showed that the nature of heavy precipitation in the studied region is substantially mixed. The primary cause of precipitation is synoptic processes, most often the activation of cyclogenesis on the polar front under the condition of the invasion of cold air. However, the contribution of the “lake effect” (which is expressed in large values of heat and moisture fluxes from the Caspian Sea surface) and orography (which initiates the oonvergence of moisture on the windward side of the Elborz Mountains) is large and in average is about 50%. With an increase in the temperature of the surface of the Caspian Sea, which is possible in the climatic conditions of the future, percentage of heavy precipitations increases first.

First Record of Harry Hotlips Plectorhinchus gibbosus (Lacepède, 1802) (Perciformes: Haemulidae) From the Iranian Coast of the Gulf of Oman

Harry hotlips (Plectorhinchus gibbosus), belonging to the fish family Haeumulidae, is recorded for the first time off the Iranian coast of the Oman Sea, Chabahar Bay (25°18′N, 60°37′E). Identification confirmed by comparing morphological data of the collected specimen with data of reported congener species off this area.

Annotated checklist of the snapping shrimps of the genus Alpheus Fabricius, 1798 (Crustacea: Decapoda: Alpheidae) from the Persian Gulf and Gulf of Oman, Iran

In the present study, shrimps belonging to the genus Alpheus from the Persian Gulf and Gulf of Oman are documented based on the existing literature and extensive new sampling from 2013 to 2018 along the Iranian coast. A total of 35 species are recorded from the region, of which 40% (14 species) and 60% (21 species) are new records for the Persian Gulf and Gulf of Oman, respectively. Among 19 sampling localities, A. lobidens De Haan, 1849, A. edwardsii (Audouin, 1826) and A. edamensis De Man, 1888 occurred in 14, 13 and 9 localities, respectively. Among the visited habitats, 14 species (40%) were associated with coral or other sessile invertebrates, 13 species (37%) were collected on sandy or rocky substrates, five species (14%) were obtained from muddy substrates, and three species (9%) were found associated with goby fishes. Among Alpheus species, three (10%) were endemic to the Persian Gulf. Most taxa show affinities to both western Indian Ocean and East Indian/West Pacific Oceans.