Biological parameters of interbreeding subspecies of Meccus phyllosomus (Hemiptera: Reduviidae: Triatominae) in western Mexico

2015 ◽  
Vol 105 (6) ◽  
pp. 763-770 ◽  
Author(s):  
J. A. Martínez-Ibarra ◽  
B. Nogueda-Torres ◽  
M. Á. Cárdenas-De la Cruz ◽  
M. E. Villagrán ◽  
J. A. de Diego-Cabrera ◽  
...  

AbstractUnderstanding the biological parameters of some triatomine subspecies of Meccus phyllosomus (Burmeister) is a crucial first step in estimating the epidemiological importance of this group. Biological parameters related to egg eclosion, egg-to-adult development time, number of blood meals to moult, percentage of females at the end of the cycle, number of laid eggs, and the accumulative mortality for each instar of three M. phyllosomus subspecies [Meccus phyllosomus pallidipennis (Stål), Meccus phyllosomus longipennis (Usinger), and Meccus phyllosomus picturatus (Usinger)] as well as their laboratory hybrids were evaluated and compared. No significant differences (P > 0.05) were recorded among the experimental hybrids (M. p. longipennis × M. p. pallidipennis, M. p. longipennis × M. p. picturatus, M. p. pallidipennis × M. p. picturatus) and reciprocal cohorts. In five of the six studied parameters (egg eclosion, egg-to-adult development time, number of blood meals to moult, number of laid eggs and accumulative mortality), with the exception of the non-significant percentage of females obtained among all the studied cohorts, at least one of the parental cohorts in each set of crosses exhibited better fitness results than by those of their hybrid descendants. The lack of hybrid fitness in our study indicates the maintenance of reproductive isolation of parental genotypes. Moreover, the results lead us to propose that an incipient speciation process by distance is currently developing among the three studied subspecies, increasing the differences between them that modify the transmission efficiency of Trypanosoma cruzi to human beings in Mexico.

2019 ◽  
Vol 57 (1) ◽  
pp. 33-38 ◽  
Author(s):  
J Alejandro Martínez-Ibarra ◽  
Tzintli Meraz-Medina ◽  
Benjamin Nogueda-Torres ◽  
María E Villagrán-Herrera ◽  
Jose A de Diego-Cabrera

Abstract This study reports the third collection of Triatoma nitida Usinger in Mexico, with a brief description of the collection area and an investigation of parameters related to its vectorial capacity. Whether a triatomine (Hemiptera: Reduviidae) species is a primary or secondary vector is determined by factors that include vectorial capacity, anthropophilic habits, geographic distribution, and capacity to invade and colonize human dwellings. However, when the primary vectors are removed, secondary vectors, such as T. nitida, can become important transmitters of Trypanosoma cruzi Chagas to humans. To estimate the vectorial capacity of T. nitida, the egg-to-adult development time, number of blood meals required to molt to the adult stage, accumulative mortality, onset time for feeding, and feeding and defecation times were examined. Triatoma nitida (n = 100) required a median of 590 d to complete its development time, with a median of 31 blood meals. Almost half (46.5%) of the nymphs died during the cycle. The onset of feeding time exceeded 5 min in all nymphal instars (except on fourth-instar) and adults and feeding times exceeded 22 min in all instars, except on first-instar nymphs. No defecation was observed for 65.6% (n = 383) of the triatomines during a 30-min observation period. Based on the six parameters, the vectorial capacity of T. nitida should be considered as low. However, surveillance programs should include this species because the potential importance of T. nitida as a vector has been demonstrated in other countries.


2020 ◽  
Vol 57 (5) ◽  
pp. 1390-1398
Author(s):  
José Alejandro Martínez-Ibarra ◽  
Benjamín Nogueda-Torres ◽  
Oziel Dante Montañez-Valdez ◽  
J Guadalupe Michel-Parra ◽  
Ricardo Valenzuela-Campos

Abstract Chagas disease is one of the most important vector-borne diseases in Latin America, including Mexico. Recently, autochthonous cases have also been detected in the United States of America. It is suspected that two subspecies of Triatoma rubida (Uhler), T. r. sonoriana (Usinger) and T. r. uhleri (Usinger), considered efficient vectors of Trypanosoma cruzi Chagas in Mexico, could interbreed and potentially generate offspring with superior biological characteristics. In this study, the biological parameters of T. r. sonoriana, T. r. uhleri and their laboratory hybrids were evaluated. Hybrids of the two subspecies surpassed both parental subspecies, T. r. sonoriana and T. r. uhleri, in three (numbers of required blood meals to molt [16–20], feeding [10.5–17 min] and defecation times [˂1 min post-feeding]) of nine studied biological parameters. Moreover, the hybrids surpassed T. r. uhleri in two additional parameters, development time (298 d) and mortality (39–42%). Both the hybrid and the two parental cohorts had comparable results in the remaining four (onset of feeding, number of obtained females, number of eggs laid, and eclosion rate) of nine studied parameters. Thus, we conclude that hybrid vigor could result in an increased risk of T. cruzi transmission to humans and animals.


2014 ◽  
Vol 18 (3) ◽  
pp. 368-376 ◽  
Author(s):  
P. Mohamed Shameer ◽  
K. Sowmithra ◽  
B. P. Harini ◽  
R. C. Chaubey ◽  
S. K. Jha ◽  
...  

Genetics ◽  
1994 ◽  
Vol 136 (4) ◽  
pp. 1373-1384
Author(s):  
H Hollocher ◽  
A R Templeton

Abstract An association between quantitative variation of rDNA on the Y chromosome and male expression of the juvenilized, adult cuticle of the abnormal abdomen syndrome has been found for Drosophila mercatorum. Many pleiotropic effects of this syndrome have been described previously for females, but little was known about possible pleiotropic effects in males. The effects on males open up new avenues for the action of natural selection operating on the system. In females, the syndrome causes an increase in egg-to-adult development time, precocious sexual maturation, increased fecundity and decreased longevity. In addition to the cuticle phenotype, in males abnormal abdomen causes delayed sexual maturation, increased longevity, and decreased mating success, yet no change in egg-to-adult development time. Thus the syndrome has opposing fitness effects in the two sexes, which may help explain the genetic polymorphism observed in this system. Although investigated intensively, associations between naturally occurring Y-linked polymorphism and fitness phenotypes have not been found in Drosophila melanogaster.


Zootaxa ◽  
2011 ◽  
Vol 2733 (1) ◽  
pp. 49 ◽  
Author(s):  
JOHN T. HUBER ◽  
CATHERINE W. GITAU ◽  
GEOFF M. GURR ◽  
CHARLES F. DEWHURST ◽  
MURRAY J. FLETCHER

Both sexes of Parastethynium maxwelli (Girault), a parasitoid of Zophiuma lobulata Ghauri eggs on coconut and oil palm in Papua New Guinea, are described and illustrated. The second known species in the genus Parastethynium, P. hirsutum Huber sp. n., from Indonesia (Sulawesi) is also described. The latter represents the first record from the Oriental region. The basic biology of P. maxwelli is presented. Mean progeny produced per female was 57 with a female proportion of 0.59. Mean egg to adult development time was 11 days, at 24.5 o C−29.7 o C and 72−93% relative humidity. Survival time of females and males fed on honey and water was longer compared to males and differed significantly with those provided with water only or nothing at all.


1986 ◽  
Vol 76 (1) ◽  
pp. 109-117 ◽  
Author(s):  
Penelope B. Edwards

AbstractThe development of Onitis caffer Boheman in cattle dung was studied in the laboratory. The larvae feed on the dung in which the eggs are laid. Egg to adult development at 25°C was completed in 24·7 weeks by a strain from a winter rainfall (WR) area of South Africa and 29·4 weeks by a strain from a summer rainfall (SR) area, and occurred without diapause. Maximum larval dry weight was achieved mid-way through the third larval instar, after which the larva emptied much of its gut to form a protective faecal shell, in which pupation occurred. At 20°C, 20% of WR larvae developed without diapause and the adults emerged after 33·5 weeks, whereas the remaining 80% of adults emerged after 80·1 weeks. In the SR strain, 70% emerged after 37·1 weeks without having entered diapause, while the remaining 30% emerged after 83·8 weeks. Thus, the period of diapause for both strains was 47 weeks and occurred in the third larval instar. At 15°C, 74% of WR larvae had pupated by 153 weeks, with a mean development time of 121·8 weeks. Zero development temperatures were 10·4°C (WR) and 10·1°C (SR), and day-degree requirements for development without diapause at 20°C were 2251 (WR) and 2571 (SR).


2020 ◽  
Vol 72 (2) ◽  
pp. 181-192
Author(s):  
Erinç Çelik ◽  
Olga Sak

The effects of the cytokinin hormone kinetin on the life history traits and hemocytes of the smaller wax moth Achroia grisella F. (Lepidoptera: Pyralidae) were examined in order to better understand the physiological impacts of plant growth regulators on insects. Based on the obtained results, it was found that kinetin did not lead to significant changes in larval mortality, development time, morphological disorders and egg fertility. Female and male longevity were almost unchanged when early instars were fed with a kinetin-added diet, and it tended to be higher for males when kinetin was applied at the egg stage, especially at 5 mg/L. The weight of females decreased significantly with 25 and 3000 mg/L of kinetin and that of males with 5 mg/L. The most striking effect was a considerable decline in the number of progeny, particularly at 400 and 3000 mg/L, as compared to the control. The injection of kinetin caused noticeable decreases in the number of hemocytes in the circulation at 3 and 24 h. This work presents the first evidence that kinetin adversely affects the development and the hemocyte counts of an economically-important host species, A. grisella.


1991 ◽  
Vol 69 (2) ◽  
pp. 512-527 ◽  
Author(s):  
Graham J. McMillan

The six naupliar and six copepodite stages of the harpacticoid copepod Amphiascus undosus Lang are described in detail. Thoracic leg segmentation and armature are presented in tabular form for the copepodite stages. The species becomes sexually dimorphic at the fourth copepodite stage. Average egg-to-adult development time is approximately 31.5 days at 22 ± 1 °C. Up to four successive pairs of egg sacs from a single female are produced in the laboratory, yielding a maximum of 76 progeny. Some discrepancies exist between the original description of the California type specimens and the present British Columbia material, particularly in the adult male maxillule, maxilliped, and first, fifth, and sixth legs, and the caudal setae of the adult female. A brief comparison is made with the developmental similarities and differences of six other diosaccid harpacticoid copepods.


Sign in / Sign up

Export Citation Format

Share Document