Recent change in the annual pattern of sexually transmitted diseases in the United States

This study analyzed the 1999 to 2003 database of the Center for Disease Control and Prevention (CDC) for seasonal and longer-term time trends in the sexually transmitted diseases (STDs) of chlamydia, gonorrhea, and syphilis in the United States. Linear regression was used to ascertain time trends, and a linear mixed auto-regression model was applied to determine the statistical significance of the major peaks relative to the annualized time series mean. A statistically significant increasing trend during the 5 yr span was documented only in the incidence of chlamydia. No clear annual periodicity was detected in any of the STDs; instead, significant three-month cycles were documented in all the STDs, with prominent peaks evident in March, May, August, and November. The March and May peaks could be associated with the sexual activities of young adults during spring break, which for different colleges and universities, commences as early as mid- to late-February and concludes as late as early- to mid-April, when huge numbers of sexually active youth congregate at beach resort settings. We propose the August peak is representative of summer sexual activity, in particular, of youths during school recess when adult supervision is poor. Finally, the autumn peak seems to be an expression of an endogenous annual rhythm in human reproductive biology, exemplified by elevated levels of testosterone in young males and sexual activity at this time of the year.     

The reproductive cycle of the Nile crocodile (Crocodylus nilotkus)

The reproductive cycle of the Nile crocodile ( Crocodylus niloticus ) was studied in Zimbabwe. Females attained sexual maturity after they had reached a total length of about 262 to 287 cm and males, 270 to 295 cm. Some adult females did not reproduce every year. Follicle growth and vitellogenesis occurred from April to mid August during the dry winter. During this time reproductive females had elevated levels of plasma oestradiol-17β, testosterone, calcium and magnesium, but lowered levels of iron. The measuring of plasma calcium was an 'early pregnancy' test, reliable up to four months before nesting. Elevated levels of plasma testosterone in reproductive females corresponded to the time of courtship and mating. Ovulation occurred during the latter half of August. Males had viable sperm from mid May to mid September, during the winter. Courtship and mating occurred from late June to mid August, when crocodiles were confined to pools. Females nested on the higher sand ridges in the dry river bed from early September to early October, and eggs hatched during December.     

Seasonal activity patterns of Ixodes pacificus nymphs in relation to climatic conditions

Abstract In western North America, the tick Ixodes pacificus Cooley & Kohls (Acari: Ixodidae) is the primary vector to humans and domestic animals of the disease agents causing Lyme disease and granulocytic ehrlichiosis. We examined the seasonal activity patterns of I. pacificus nymphs over a 4‐year period, including the wet and cold El Niño winter/spring of 1998, in a dry oak/madrone woodland, and for one year in a cooler and moister redwood/tanoak woodland in Mendocino County, California. Linear regressions were used to estimate when nymphal densities first exceeded and then fell below 25, 50 and 75% of the recorded yearly peak densities. In oak/madrone woodland, nymphs typically were active by mid‐March, reached 50% of their yearly peak densities in early to mid‐April, peaked by early May, fell below 50% of their peak densities by early to mid‐June, and were absent by late July to mid‐August. The lengths of the periods with nymphal densities exceeding 50 and 75% of the recorded yearly peaks in oak/madrone woodland were associated positively with rainfall and negatively with maximum air temperatures during April–May. Moreover, nymphal numbers typically reached 50% of their peak 10–15 days later, remained at levels above 50% of the peak 1.3–1.5 times longer, and started declining 4–6 weeks later under cooler, moister climatic conditions (oak/madrone woodland in 1998 and redwood/tanoak woodland in 2000) relative to warmer, drier conditions (oak/madrone woodland in 2000–2001). In oak/madrone woodland, nymphal densities typically started to decline when mean maximum daily air temperatures exceeded 23°C. Nymphal densities were higher in dry oak/madrone relative to moist redwood/tanoak woodland from mid‐March to late May 2000, similar in both habitat types in early June, but higher in redwood/tanoak woodland from late June onwards. We conclude that large‐scale studies of the density of I. pacificus nymphs in California need to consider spatial variation in the length of nymphal activity periods and select temporal sampling regimens that yield representative data for all included habitat types.     

Effects of decadal climate change on zooplankton over the last 50 years in the western subarctic North Pacific

Decadal‐ to multi‐decadal variations have been reported in many regional ecosystems in the North Pacific, resulting in an increasing demand to elucidate the link between long‐term climatic forcing and marine ecosystems. We detected phenological and quantitative changes in the copepod community in response to the decadal climatic variation in the western subarctic North Pacific by analyzing the extensive zooplankton collection taken since the 1950s, the Odate Collection. Copepod species were classified into five seasonal groups depending on the timing of the annual peak in abundance. The abundance of the spring community gradually increased for the period 1960–2002. The spring–summer community also showed an increasing trend in May, but a decadal oscillation pattern of quasi‐30‐year cycles in July. Phenological changes coincided with the climate regime shift in the mid‐1970s, indicated by the Pacific decadal oscillation index (PDO). After the regime shift, the timing of the peak abundance was delayed one month, from March–April to April–May, in the spring community, whereas it peaked earlier, from June–July to May–June, in the spring–summer community, resulting in an overlap of the high productivity period for the two communities in May. Wintertime cooling, followed by rapid summertime warming, was considered to be responsible for delayed initiation and early termination of the productive season after the mid‐1970s. Another phenological shift, quite different from the previous decade, was observed in the mid‐1990s, when warm winters followed by cool summers lengthened the productive season. The results suggest that climatic forcing with different decadal cycles may operate independently during winter–spring and spring–summer to create seasonal and interannual variations in hydrographic conditions; thus, combinations of these seasonal processes may determine the annual biological productivity.     

Population dynamics of the cattle tick Rhipicephalus (Boophilus) microplus in a subtropical subhumid region of Argentina for use in the design of control strategies

The population dynamics of Rhipicephalus microplus (Ixodida: Ixodidae) in northwest Argentina was analysed to support the design of strategic methods for its control. Both parasitic and non‐parasitic phases were studied. The seasonal activity of R. microplus in its parasitic phase was characterized by three peaks in abundance: the first in mid–late spring; the second in summer, and the third in autumn. The non‐parasitic phase of R. microplus was characterized by a long total non‐parasitic period observed after exposures of females from mid‐summer to early autumn, a short total non‐parasitic period observed after exposures of females from late winter to late spring, a short period of larval longevity in early and mid‐summer, and no hatch of the eggs produced by females exposed in mid‐ and late autumn and winter. Treatments of cattle administered during the period from late winter to late spring will act on small cohorts of R. microplus, preventing the emergence of larger generations in summer and autumn. A 17‐week spelling period starting in late spring and early summer will be necessary to achieve optimal control of R. microplus free‐living larvae. If spelling begins in mid‐ or late summer or in autumn, the required period will be 26–27 weeks.     

中国水蛇Enhydris chinensis （Gray）生殖周期与生殖型式的研究

中国水蛇于7月末8月初精子发生开始新的周期性复生,大部分为精母细胞。10—12月以至次年1月初大部分为成熟精子及变态中的精细胞,精子贮于附睾或输精管中过冬。11月至次年5月大部分输卵管中也存有精子。雌水蛇一年一次排卵,卵胎生。5月末至6月初见有蛇胚,孕妊期78—84天,8月中旬至9月中旬产仔蛇,每胎产仔6—21条。     

Impact of a Labour Disruption Affecting Local Public Health on the Incidence of Chlamydia Infections in Toronto

Introduction

Labour disruptions that interrupt services can be a natural experiment to examine the effect of halting a program. A five-week municipal labour disruption in Toronto during the summer of 2009 provided an opportunity to investigate the impact of reduced sexual health services.

Methods

We examined the incidence of reported chlamydia in Toronto during the five years (2004–2008) preceding the labour disruption and during the periods just before, during, and after the labour disruption. Comparisons of actual reports for 2009 were made to immediately adjacent periods around the labour disruption, to historical trends and to forecasted rates. Interrupted time series analysis was used to test for significant differences in the trend of reported chlamydia incidence.

Results

There was no significant difference in the trend of reported chlamydia incidence around the time of the strike. However, there was a small but significant increase in the incidence of reported chlamydia, particularly among females under 25 years old immediately following the labour disruption. The reported incidence for this group was higher than would be expected based on annual increases and projected seasonal trends.

Conclusions

There was a small increase in incidence of reported cases of chlamydia for certain groups that went beyond what is expected during the time immediately following the labour disruption. While causation cannot be implied from our ecological study, public health services may play a role in the control of sexually transmitted infections, even in the short-term. This underscores the need for future work to understand whether the changes observed can be attributed to the absence of these services.     

Seasonal development of five Cephaleuros species (Trentepohliaceae,Chlorophyta) on the leaves of woody plants and the behaviors of their gametes and zoospores

The infection cycle of five Cephaleuros species – C. aucubae, C. biolophus, C. japonicus, C. microcellularis, and C. virescens – was clarified by investigating seasonal development and gamete and zoospore behavior at study sites in Matsue, Shimane Prefecture, Japan. Fresh thalli or lesions appeared on the leaves of various woody plants from August and continued to develop in general from April to September in the following year. Gametangia and zoosporangia matured on 2‐ and 3‐year‐old leaves. Gametes were released in C. microcellularis samples collected from late March to late May and in samples of the other four species collected from late April to late July. Zoospores were released in C. biolophus, C. japonicus, and C. virescens samples collected from mid‐May to early August. In the present study, gametes did not conjugate but germinated like zoospores to produce new plants. After inoculation with zoospores and gametes that behave as asexual spores, fresh thalli or lesions became evident in 2–5 months following inoculation and gametes and zoospores were produced on the developed thalli or lesions the following year; one cycle of the infection was completed per year in the study area.     

Population parameters and reproductive biology of the Iberian hareLepus granatensis in southern Iberia

To analyse the population structure and reproductive biology of the Iberian hareLepus granatensis Rosenhauer, 1856, 498 hares (264 males and 234 females) were collected in monthly samples from October 1998 to September 1999. Females reached larger sizes than males, with approximately 400 g difference in body mass on reaching sexual maturity. The total sex ratio was 1∶1, with a bias in favour of males in winter. Sexually active males and females appeared in every month but August, when no sexually active female was found. Births occurred in every month and were more frequent between March and July. Seasonal variation in kidney fat index (KFI) followed a similar pattern in males and females, with an increase in mid-autumn and a decline at the end of winter. Reproductive activity appeared in every month, with a maximum from February to June. Reproductively hyperactive females (simultaneously pregnant and nursing) appeared in every month except in January, with a first peak in March and a second lower peak in May–June. Litter size fluctuated between 1 and 7 leverets. The most frequent gestations involved 1 or 2 foetuses. The mean annual litter size was 2.08 and the average number of litters per productive female per year was estimated to be 3.48. The maximum productivity was recorded between March and May. The total annual production of young per adult female was estimated to be 7.21. The minimum annual survival rate of young was 27.91%. On the basis of these results we propose to maintain the limit of the hunting period between October and December. We discuss the relationship between the low young/adult ratio obtained and the hunting method used.     

Precocious Mexican fruit fly methoprene‐fed males inhibit female receptivity and perform sexually as mature males

The sterile insect technique (SIT) has been used successfully for the control of fruit flies. The efficiency of this technique can be significantly reduced when sterile released insects are exposed to adverse conditions and predators, as a great number of sterile insects die before reaching sexual maturity and thus fail to mate with wild females. Treatments with juvenile hormone (JH) analogues such as methoprene (M) significantly reduce the time to reach sexual maturity by sterile Anastrepha ludens (Loew) (Diptera: Tephritidae) males. In this study, we compared the sexual performance of non‐treated sexually mature males with young males that had been sexually accelerated with M. Furthermore, we compared the ability of M‐fed males in inhibiting female remating compared with sexually mature males. Results showed that at 5 days M‐fed males had lower mating success than mature males; however, 6‐day‐old (0.1%) M‐fed males had the same amount of matings as mature 13‐day‐old males. Young 5‐ to 10‐day‐old M‐fed males also had similar number of matings as mature non‐treated 12‐ to 17‐day‐old males. There were no differences in copula duration between treatments. Moreover, there were no differences between the fertility, fecundity or refractory period of females mated with either young male fed M or normal sexually mature males. These results indicated that young males that were sexually accelerated with M have the same sexual performance as non‐treated sexually mature males. Implications of using M as a pre‐release treatment for A. ludens controlled through SIT are discussed.     

Ips typographus (L.) pheromone trapping in south Alps: spring catches determine damage thresholds

Abstract: Ips typographus is one of the major forest pests in the Italian Alps. From 1996, populations of I. typographus in Friuli‐Venezia Giulia region (NE Italy) have been permanently monitored in areas of outbreak by using pheromone traps. At the same time, damage caused by the insect was estimated annually. Preliminary analysis of the data (1996–2002) reveals some interesting information: (i) the flight activity of I. typographus is very extended and occurs over a period of about 4 months (May to August); (ii) there is a high correlation between mean captures per trap and annual damage; (iii) there is a high correlation between spring captures (May to mid‐June) and total captures (May to August), and between spring captures (May to mid‐June) and annual damage. The correlation between spring captures and damage allows the determination of a reliable risk‐damage threshold (about 5000 beetles/trap, in spring), reducing at the same time, the monitoring period and the general costs.     

Seasonal and annual variability in the quality of important forage plants on Banks Island,Canadian High Arctic

Abstract. In vitro acid‐pepsin digestibility (IVDMD), crude protein (CP), fibre, lignin, and energy content were measured for a variety of forage plants collected annually from Banks Island over five summers and three winters from 1993–1998. Summer samples were collected during mid‐June (start of growing season), mid‐July (peak of growing season), and mid‐late August (senescence). Winter samples were collected in early (November), mid‐ (February), and late‐ (April/May) winter. Samples, collected in areas of both high and low muskox density, included Carex aquatilis, unidentified Carex, Salixarctica, Dryasintegrifolia, Cassiope tetragona, Saxifraga spp., Astragalus spp., Oxytropis spp., lichen, and grass. Seasonal dynamics in forage quality during the growing season were similar to those reported elsewhere in the arctic and high arctic and were consistent across years. However, there were significant year effects in lignin, fibre, and energy content of forages and the crude protein (CP) content of C. aquatilis in winter, indicating annual differences in the quality of forage available to herbivores. The quality of forages on Banks Island was similar between areas subjected to different densities of muskox (ca. 1.6–1.9 versus 0.3 ‐ 0.4/km²) implying that quality was not affected by these grazing intensities. The Banks Island high arctic ecosystem supports an abundance of herbivores. It has been hypothesized that this is because forage quality and/or quantity are superior on Banks Island than elsewhere in the high arctic. Our results regarding forage quality are equivocal. Although the maximum CP content of forages from Banks Island was generally higher than reported elsewhere in the arctic and high arctic, CP content reported elsewhere fell within the interannual range reported from Banks Island. Fibre and energy content of forages from Banks Island were similar to slightly lower than elsewhere in the arctic and high arctic. Such comparisons must be considered in light of the interannual variability in quality we report.     

竹篦舟蛾生物学特性及防治

竹蓖舟蛾在闽北地区一年发生4代．以幼虫在竹林中缀叶为苞并在其中越冬,成虫羽化盛期分别为5月中旬、7月上旬,8月中旬、10月上旬,幼虫分别于3月上旬、5月中旬、7月上旬、8月中旬出现。4种不同药剂的正交防治试验和随机区组防治试验表明,不同药剂以各种配比进行防治均有良好防治效果．防治效果间无显差异,单一药剂以80%敌敌畏防治效果最好．与40%氧化乐果和50％甲胺磷之间均有显差异。     

Experimental manipulation reveals a trade‐off between weapons and testes

Theory predicts a trade‐off between sexually selected weapons used to secure mates and post‐copulatory traits used to maximize fertilization success. However, individuals that have a greater capacity to acquire resources from the environment may invest more in both pre‐ and post‐copulatory traits, and trade‐offs may not be readily apparent. Here, we manipulate the phenotype of developing individuals to examine allocation trade‐offs between weapons and testes in Mictis profana (Hemiptera: Coreidae), a species where the hind legs are sexually selected weapons used in contests over access to females. We experimentally prevented males from developing weapons by inducing them to autotomize their hind legs before the final moult to adulthood. We compared trait expression in this group to males where autotomy was induced in the mid‐legs, which are presumably not under sexual selection to the same extent. We found males without weapons invested proportionally more in testes mass than those with their mid‐legs removed. Males that developed to adulthood without weapons did not differ from the mid‐leg removal group in other traits potentially under precopulatory sexual selection, other post‐copulatory traits or naturally selected traits. In addition, a sample of adult males from the same population in the wild revealed a positive correlation between investment in testes and weapons. Our study presents a critical contribution to a growing body of literature suggesting the allocation of resources to pre‐ and post‐copulatory sexual traits is influenced by a resource allocation trade‐off and that this trade‐off may only be revealed with experimental manipulation.     

Melatonin in the Regulation of Annual Testicular Events in Carp Catla catla: Evidence from the Studies on the Effects of Exogenous Melatonin,Continuous Light,and Continuous Darkness

The physiological significance of melatonin in the regulation of annual testicular events in a major carp Catla catla was evaluated through studies on the effects of graded dose (25, 50, or 100 µg/100 g body wt.) of melatonin exogenously administered for different durations (1, 15, or 30 days) and manipulation of the endogenous melatonin system by exposing the fish to constant darkness (DD) or constant light (LL) for 30 days. An identical experimental schedule was followed during the preparatory (February–March), pre‐spawning (April–May), spawning (July–August), and post‐spawning (September–October) phases of the annual cycle. Irrespective of the reproductive status of the carp, LL suppressed while DD increased the mid‐day and mid‐night values of melatonin compared to respective controls. Influences of exogenous melatonin varied in relation to the dose and duration of treatment and the reproductive status of the carp. However, testicular response to exogenous melatonin (at 100 µg, for 30 days) and DD in each reproductive phase was almost identical. Notably, precocious testicular maturation occurred in both DD and melatonin‐injected fish during the preparatory phase and in LL carps during the pre‐spawning phase. In contrast, testicular functions in both the melatonin‐treated and DD fish were inhibited during the pre–spawning and spawning phases, while the testes did not respond to any treatment during the post‐spawning phase. In conclusion, this study provided the first experimental evidence that melatonin plays a significant role in the regulation of annual testicular events in a sub‐tropical surface‐dwelling carp Catla catla, but the influence of this pineal hormone on the seasonal activity of testis varies in relation to the reproductive status of the concerned fish.     

Life history and production of Agapetus quadratus (Trichoptera: Glossosomatidae) in a temporary, spring-fed stream

1. The life history and trophic basis of production of the caddisfly grazer Agapetus quadratus were studied in the torrent Gorg Blau, a spring‐fed stream on the island of Majorca that dries annually during summer. 2. Quantitative random samples were taken every 2–3 weeks during an annual surficial flow period, from November 2000 to mid‐July 2001. Instars of field‐collected larvae were determined by measurements of head width and pronotum length, and the sex of all pupae was determined to study sexual dimorphism and sex ratio. 3. Stage‐frequency histograms suggested a trivoltine population, with an average cohort time of 4 months. Larval development was asynchronous, with continuous growth and overlapping generations. Recruitment peaks were identified in mid‐November, early March and late June, indicative of winter, spring and summer generations. On average, females were larger than males and the mean sex ratio was 2 : 3 (females : males). Population densities and biomasses derived from the field data were used to calculate production and turnover rate. 4. Annual production of A. quadratus in the torrent Gorg Blau (4.80 g dry mass m^?2 year^?1) was the highest ever reported for the genus, being comparable with that estimated for some insects with rapid development and multiple cohorts. 5. Estimates of production of A. quadratus were combined with foregut content analysis to estimate the fraction of total production derived from the principal food sources: algae and organic detritus. Algae supported a major proportion of the production of this grazer. 6. The low density of predators characteristic of many temporary streams, and the small amplitudes in discharge and temperature during most of the wet period that characterise the spring habitats might allow high levels of grazer production in this particular Mediterranean stream.     

Seasonal dynamics in community structure,abundance, body size and sex ratio in two species of Neotropical annual fishes

Seven ephemeral pools on the coastal plain of southern Brazil were found to be inhabited by three annual and 22 non‐annual fish species. Two common annual species (Austrolebias minuano and Cynopoecilus fulgens) exhibited clear seasonal dynamics, with the appearance of young fishes in the austral autumn (May to June) and a decline in abundance over the seasonal cycle. The third annual species, Austrolebias wolterstorffii, was rare. No seasonal dynamics were observed in non‐annual fishes. The relative abundance of non‐annual fishes compared with annual fishes increased over the seasonal cycle, but they coexisted widely. The size structure of annual fishes suggested the presence of a single age cohort in most pools though a second age cohort was registered in one pool in August, coinciding with a large flooding. Strong sexual dimorphism in body size was found in C. fulgens throughout the seasonal cycle, while no sexual dimorphism in body size was found in A. minuano. Female‐biased sex ratios were recorded in both common annual fish species in the last three sampling dates (in spring), but not during the first two sampling dates (in winter). The natural lifespan of annual fishes was <8 months. Annual fishes disappeared before habitat desiccation in half of the pools, while non‐annual fishes were still present.     

Contrasting strategies for wing‐moult and pre‐migratory fuelling in western and eastern populations of Common Whitethroat Sylvia communis

Trade‐offs between moult and fuelling in migrant birds vary with migration distance and the environmental conditions they encounter. We compared wing moult and fuelling at the northern and southern ends of migration in two populations of adult Common Whitethroats Sylvia communis. The western population moults most remiges at the breeding grounds in Europe (e.g. Poland) and migrates 4000–5000 km to western Africa (e.g. Nigeria). The eastern population moults all remiges at the non‐breeding grounds and migrates 7000–10 000 km from western Asia (e.g. southwestern Siberia) to eastern and southern Africa. We tested the hypotheses that: (1) Whitethroats moult their wing feathers slowly in South Africa, where they face fewer time constraints than in Poland, and (2) fuelling is slower when it coincides with moulting (Poland, South Africa) than when it occurs alone (Siberia, Nigeria). We estimated moult timing of primaries, secondaries and tertials from moult records of Polish and South African Whitethroats ringed in 1987–2017 and determined fuelling patterns from the body mass of Whitethroats ringed in all four regions. The western population moulted wing feathers in Poland over 55 days (2 July–26 August) at a varying rate, up to 13 feathers simultaneously, but fuelled slowly until departure in August–mid‐September. In Nigeria, during the drier period of mid‐February–March they fuelled slowly, but the fuelling rate increased three‐fold in April–May after the rains before mid‐April–May departure. The eastern population did not moult in Siberia but fuelled three times faster before mid‐July–early August departure than did the western birds moulting in Poland. In South Africa, the Whitethroats moulted over 57 days (2 January–28 February) at a constant rate of up to nine feathers simultaneously and fuelled slowly from mid‐December until mid‐April–May departure. These results suggest the two populations use contrasting strategies to capitalize on food supplies before departure from breeding and non‐breeding grounds.     

Phenology and life cycle of the annual, <Emphasis Type="Italic">Chamaesyce maculata</Emphasis> (L.) Small (Euphorbiaceae), with multiple overlapping generations in Japan

The phenology of germination, vegetative growth and sexual reproduction in the annual Chamaesyce maculata (L.) Small (Euphorbiaceae) were investigated in a natural population in western Japan. Seedlings emerged from mid-June to early October, with three peaks: mid-June, late July and late August. Plants that emerged in June commenced sexual reproduction from late July, and thereafter both vegetative growth and sexual reproduction occurred together until early November, the plants showing no switching from vegetative growth to sexual reproduction. Seedlings that emerged in June and July suffered high mortality, but most seedlings that emerged from August onward survived until the reproductive stage. The minimum size for reproduction was largest for plants that emerged early in the season, and it decreased with a delay in seedling emergence. The late emergence of seedlings that resulted in low reproductive output may be to some extent compensated for by the increased probability of survival in the seedling stage. A transplant experiment clarified that C. maculata can repeat a maximum of three overlapping generations within a year. Multiple generations per year were attained by non-dormant seeds produced in the first and second generations and clearly resulted in an increased reproductive output per year. The life cycle with multiple overlapping generations may have been acquired in habitats where unpredictable disturbance results in temporally unsuitable conditions for germination, vegetative growth and sexual reproduction of annual plants, but where suitable conditions frequently continue over a period longer than the single generation time of annual plants.     

Histomorphological and endocrine assessment of female Arabian carpetshark,Chiloscyllium arabicum (Elasmobranchii: Hemiscylliidae) from the Persian Gulf during annual reproductive cycle

The present study aimed at assessing the annual reproductive cycle of female Arabian carpetshark, Chiloscyllium arabicum from the Persian Gulf by a macroscopic and microscopic evaluation of the reproductive tract. The annual cycle of gonadal steroids [17β-estradiol (E2), progesterone (P4) and testosterone (T)] was also assessed in this shark. In total, 130 female C. arabicum were collected from the Bahrakan Creek (located northwest of the Persian Gulf) between January 2018 and March 2019. Females were oviparous with an external-type ovary and only one functional ovary. Five sexual maturity stages were recognized based on macroscopic and microscopic evaluation: Immature I (August–October), Immature II (November–January), Mature (February–March), Pregnant (April–May) and Spent (June–July). The structural changes in the oviducts, oviducal glands and uterus throughout the annual reproductive cycle were consistent with their roles in the egg movement, the egg capsule production and sperm storage. The plasma levels of the gonadal steroids were associated with morphological changes in the reproductive tract. E2 showed two detectable peaks during March (close to ovulation) and June (just before mating). P4 and T displayed a peak just before ovulation.