1T. eugenii en México Folia Entorno/. Mex., 42(2): 161-168 (2003)
· ows. Media Cybemetics, Silver Spring,
. A WHARTON. 2000. Toxoneuron (Hy mdae): designation of a neotype for its ON THE REPRODUCTIVE BEHAVIOR AND POPULATION ECOLOGY and discovery of a possible senior syno ow species, T. nigriceps. Annals of the OFLETHOCERUSCOLOSSJCUSSTÁL tety ofAmerica, 93(2): 208-219 . (HETEROPTERA: BELOSTOMATIDAE) .enópteros parasitoides de Apion spp. honmdea: Apionidae) en Tepoztlán Mo- ológica Mexicana, 63: 39-46. ' R. A WHARTON 1997. Morphology and RüGELIO MACÍAS-ORDÓÑEZ 9-37. In: Wharton, R. A, P M. Marsh eds.). Manual ofthe New World Genera nidae (Hymenoptera). lntemational So Departamento de Ecología de Comportamiento Animal, Instituto de Ecología, A.C., Apartado Postal 63, Xalapa, Veracruz ists. Special publication l. 91000, México. Correo electrónico:
Giant water bugs (Heteroptera: Belostomatidae) family Belostomatinae have long been known to are large carnivorous aquatic insects, and repre exhibit exclusive mal e parental care in which the sent the great majority of arthropod species exhi female lays the eggs on the male's back; males biting exclusive maJe parental care described so then perform specific behavioral pattems in order far (Smith, 1997). All extant genera from the sub- to provide optimal conditions for embryologic Macías-Ordóñez: Reproduction and population ecology ofLethocerus colossicus development (Smith, 1976). to Morelos" Research Station (ICMyLIUNAM). ter, surrounded by dense vege1 The monotypic subfamily Lethocerinae has The station is located on the East shoreline ofthe perature at the surface was 28' been proposed as the most primitive ofthe family Yucatán Península on the Mexican Caribbean the study, with variations ofle! (China, 1955; Lauck and Menke, 1961; Mahner, (20°52' N, 86°52' W). was 40+ meters (maximum de 1993 ). It in eludes only one extant genus, Letho After assessing body wear ( see below) and due SCUBA, the bottom could no1 cerus, distributed worldwide. A form ofparental to laboratory space limitations, only the first 100 signs of macrobiota were obs~ care, different from that of Belostomatinae, has picked were kept in individual one-liter contai meters. Adult L. colossicus ob! been described more recently in two species of ners, the remaining males were released ( n= 15 ) were captured using a hand net lethocerines: L. deyrollei (lchikawa, 1988) and L. and the remaining females were eutanized and and uniquely tagged with nail medius (Smith and Larsen, 1993 ). In these spe later dissected to count mature eggs in ovaría (n pulation size was estimated u cies, females !ay eggs on emergent substrate bet = 26). The sex of adults was determined by sex average method (Begon, 197S ween repeated mal e genitalic intromissions. Only specific differences at the tip ofthe genital oper removed from this pond. Re1 the male stays to brood the eggs, spending varia culum (males have a rounded tip while females larval instars were also made ble periods oftime underwater, but with variable present a small indentation). Sex and body assessed by size, based on av< frequency climbs out ofthe water to moisten the length (excluding siphons) of kept adults were boratory reared hatchlings (see clutch with water dripping from his proboscis recorded the next moming (out of the 100, six number of clutches produced (lchikawa, 1995). Brooding males also exhibit escaped ovemight before their sex and period was estimated as the behavioral pattems that suggest defense against measurements could be obtained), as well as number of days of continuo1 predators. Brooding behavior continues for the weight of a random sample of 60 adults. instars 1 in the cenote divided entire embryologic development and ends soon Adults collected were fed live Gambusia sp. time in the lab culture. after hatching. In a recent review ofbelostomatid fish every other day under a·l2L:l2D light pe As an indicator of age, body reproductive behavior, Smith (1997) stated that riod. Thirty-eight male-female pairs were placed by recording loss ofleg sectim "the complexity and variety in brooding pattems each in 160 l aquaria in 15 cm of water depth, flying and cenote individuals. shown among the few Lethocerus spp. studied with two wood perches (40 cm long and 2-3 cm tact adults in both samples we clearly suggests the need for more intensive work in diameter). Courtship, mating and brooding be a chi-square analysis on a 2x2 on previously studied species as well as a survey havior were recorded. Pairs were observed every (Siegel and Castellan, 1988). of brooding pattems in al! members of this three hours until sorne interaction ( courtship or Analyses ofsex ratio bias we genus". mating) was detected, in which case continuous the binomial test (Siegel anc The biology of L. colossicus, one ofthe largest focal observations were made throughout the in considering a 1: 1 sex ratio as t aquatic insects, has not been previously studied. teraction. Differences in sex ratio betw Mating and brooding on emergent substrate in L. In order to record size and length of instars, note samples were also com¡ colossicus are described in this paper, and dis eggs from one clutch laid on a brick (provided as square analysis on a 2x2 cont cussed in the context ofprevious research. l also grasping substrate) by one ofthe collected fema xual dimorphism was analyze compare flying L. colossicus (collected when les, were kept ¡poistened. Upon hatching, hatch t test on length and weight dat attracted to lights) to those found in permanent lings were individually reared and fed live Gam re two tailed except those on s water and discuss dispersion pattems, sex ratio, busia sp. fish. the altemate hypothesis was a population size and reproductive activity. Thirty four field censuses were conducted on a ratio, as found in other belos L. colossicus population, between 19:00 (dusk) ring, 1932; Kraus, 1989a). Me MATERIAL AND METHODS and 22:00 hrs, from April21 through September in parentheses. A sample of 141 "flying" adults ofL. colossicus 15, 1991. The site was a permanent cenote (Ma- was collected the night ofMarch 21, 1991. They yan word for natural ponds in the area, formed RESULTS were hand-picked while crawling on the floor af- by collapse ofunderground river caves) located Sexual Dimorphism and F ter heavy rainfall, when attracted by the light of 13 km inland west of the research station. The tive Status. Females were laq lamps in parking lots and open halls at the "Puer- cenote was nearly round,.l4.5 meters in diame- 162 rLethocerus colossicus Folia Entorno!. Mex., 42(2) (2003)
. arch Station (ICMyLIUNAM). ter, surrounded by dense vegetation. Water tem 2.5 mm) than males (n= 35, 71.52 ± 2.4 mm) (t= ated on the East shoreline ofthe perature at the surface was 28°C during most of 12.2, p< 0.001) in terms ofbody length (exclu la on the Mexican Caribbean the study, with variations ofless than 1°C. Depth ding syphons). Females were also heavier (n= 'W). was40+ meters (maximum depth reached using 34, 1O. 7 ± 1.6 g) than males (n= 26, 8.21 ± 1.3 bodywear(see below) and due SCUBA, the bottom could not be observed), no g) (t= 6.9, p< 0.001 ). Out of 26 dissected e limitations, only the first 100 signs of macrobiota were observed be1ow se ven females from the flying population, only three in individual one-liter contai meters. Adu1t L. colossicus observed in this pond (11.5%) had mature eggs in ovaria (67, 48 and 2 g males were released (n= 15 ) were captured using a hand net, measured, sexed, eggs for each female). g fema1es were eutanized and and uniquely tagged with nail polish. Adult po Sex Ratio. Sex ratio was female biased in both count mature eggs in o varia (n pulation size was estimated using the weighted samples: flying adults (50 males : 85 females) , adults was determined by sex average method (Begon, 1979). No adults were (Binomial test, p< 0.001) and the cenote popula s at the tip ofthe genital oper removed from this pond. Records of observed tion (4 males : 12 females) (Binomial test, p= e a rounded tip while females larval instars were also made, instar stage was 0.011 ). There was no significant difference bet indentation). Sex and body assessed by size, based on average length of la ween the sex ratios of these samples (Chi siphons) of kept adults were boratory reared hatchlings (se e below ). Minimum square= 0.45, d.f.= 1, p= 0.5). moming (out ofthe 100, six number of clutches produced along the census Body Wear. A significantly larger proportion t before their sex and period was estimated as the ratio between the ofindividuals (8 out of 16, 50%) from the cenote Id be obtained), as well as number of days of continuous observation of population was missing either wing tissue or leg sample of 60 adults. instars 1 in the cenote divided by average instar sections when compared with those ofthe flying were fed live Gambusia sp. time in the lab culture. population (6 out of 141, 4.3%) (Chi-square= y under a ·12L: 12D light pe As an indicator of age, body wear was assessed 19.76, d.f.= l, p< 0.001). ale-female pairs were placed by recording loss ofleg sections or wing tissue in Demography. Three clutches ofeggs were ob ·a in 15 cm ofwater depth, flying and cenote individuals. Frequencies of in tained in the laboratory consisting of38, 33 and hes ( 40 cm long and 2-3 cm tact adults in both samples were compared using 58 eggs respectively. Two clutches were found ip, mating and brooding be a chi-square analysis on a 2x2 contingency table in stock tanks containing severa! adults of both . Pairs were observed every (Siegel and Castellan, 1988). sexes, the third was laid by a paired female (see e interaction ( courtship or Analyses of sex ratio bias were performed using below). Table l shows developmental data from , in which case continuous the binomial test (Siegel and Castellan, 1988) the eleven hatchlings that resulted from the ere made throughout the in- considering a 1: 1 sex ratio as the null hypothesis. clutch of 33 eggs, raised in the laboratory. Differences in sex ratio between flying and ce Adult population size for the cenote was es size and Iength of instars, note samples were also compared using a chi timated to be around 17 adults (16.57 ± 2.98) as laid on a brick (provided as square analysis on a 2x2 contingency table. Se estirriated from recapture data on 16 individuals. one ofthe collected fema xual dimorphism was analyzed using a student's This adult population was reproductively active ed. Upon hatching, hatch t test on length and weight data. All analyses we as shown by the continuous presence of early ly reared and fed live Gam- re two tailed except those on sex ratio bias where instars observed during the censuses. lnstars 1 to the altemate hypothesis was a female biased sex IV were observed throughout the study period , uses were conducted on a ratio, as found in other belostomatids (Chicke (April21-September 15, 1991; 148 days). Assu :on, between 19:00 (dusk) ring, 1932; Kraus, 1989a). Mean± s.d. are shown ming instar duration values from the laboratory ril21 through September in parentheses. culture (ten days for instar 1), at least eigh bat a permanent cenote (Ma ches hatched during such period (instars 1 c,oser nds in the area, formed RESULTS ved on days 36, 43, 45, 52, 55, 61, 67, 70, 71, ound river caves) located Sexual Dimorphism and Female Reproduc 81, 111, 125, 129, 148). the research station. The tive Status. Females were larger (n= 59, 77.94 ± d, 14.5 meters in diame- 163 Macías-Ordóñez: Reproduction and population ecology ofLethocerus colossicus
Table 1 was no interaction in the next Size and duration of L. colossicus instars from one clutch of eggs. Body length, excluding siphons, in millimeters; duration in mal e was dissected and found t days; s.d., standard deviation; n, sample size for each instar. Decrease in sample size is dueto instar mortality during mature eggs. development; also the reason for different within-instar sample size values for size and duration. As the first two pairs, a four1 served to perform an abov( Body length Duration They copulated two consecu Instar Mean sd n Mean sd n water, and remained "mounti.J: 14.02 0.44 11 9.7 0.95 10 ween. They did not copulate
II 20.85 0.72 10 6.7 1.00 9 next four days and, on the fif 58 eggs was found 20 cm abe III 31.07 0.69 9 9.7 2.63 7 one of the perches. Behavior ' IV 42.73 1.48 5 19.0 0.00 4 was not observed. The follov V 58.99 1.10 4 48.0 0.00 rived from observations ofthi Paternal Care. The male n me perch, mostly resting on th• Courtship and Copulation. The following lum. The mal e then m oves to one si de ( either figure 1, for the whole perioc descriptions, listed in the observed order, include one) and stands on that half of the female, raises courtship and copulation behavioral pattems ob his genital operculum and extrudes the penis, in development. Only once or t\1 served in four pairs in the lab. serting it in the female's vagina. The pair remains descended to the water for r "Display Pumping": Standing horizontally on static between 1O and 25 minutes. minutes, and climbed back to This was performed by inser substrate, 1 cm below the surface, the mal e flexes During "mounting", the pairs could altemate into the spaces between th( the middle and back legs simultaneously and between this behavior and "standing together" for would assume a threatenir rhythmically, so the body moves up and down, up to 15 hours. Males performed "stroking" only approached closer than 15 or: approximately with a 2 hz frequency. This pro on sorne mounts, "copulation" was observed only for instance ), apparently tr duces water waves that cover the whole surface after "stroking" when performed under water (se e "aggressor" with his fore legs in the tank. below). "Standing Together": The female approaches During "copulation", the pair could altemate water, the male would quickl: clutch and "defend" it when tl the male and stands just next to, or below, him, between this behavior and "mounting" or "stan parallel, both facing the same direction, within 5 ding together" for up to four hours. more than 5 meters away fror cm of each other. As the female reaches this po Two pairs performed this sequence of beha The female was kept in the sition the mal e stops "display pumping". This po viors, always below water leve! and always at never seen on the clutch. Onl: sition may last from a few seconds to many night; one ofthem, on two consecutive nights. In climb the perch and the male hours. a third pair, during "mounting", the female clim and the clutch blocking her mained touching each other's "Mounting": The mal e crawls and stands on the bed out ofthe water, on one ofthe perches, toa two hours until the female female's back with his body aligned to hers, and height of20 cm above the surface, with the male pointing in the same direction. This position may still on her back. She stood facing down and the water. After eight days, six nymph: last from a few seconds to many hours. male started a succession of"mounting", "copu "Stroking": While mounting, the male touches lation" (not preceded by "stroking" and lasting 58 eggs and the male remaim repeatedly the head of the female with only one from 12 to 20 minutes), and "descending" to the day. The female had been fe of his fore legs at anyone time, altemating them water. "Descending" !asted from three to eight just after the eggs hatched shc rhythmically and continuously. This behavior !as minutes before coming back up, to another found to contain 34 mature e: ted up to three minutes. "mounting" or straight to "copulation". "Descen "Copulation": The female slightly bends the ding" always followed "copulation" in all eight DISCUSSION pronotum and raises (opens) her genital opercu- bouts that occurred in six hours; after this, there Belostomatids represent a 1 ting taxon given that the grea 164 Folia Entamo!. Mex., 42(2) (2003)
was no interaction in the next six days. This fe siphons, in millimeters; duration in is due to instar mortality during male was dissected and found to contain only two for s1ze and duration. mature eggs. As the first two pairs, a fourth pair was not ob served to perform an above-water sequence. They copulated two consecutive nights under n water, and remained "mounting" the day in bet 0.95 10 ween. They did not copulate again during the 1.00 9 next four days and, on the fifth day, a clutch of 2.63 7 58 eggs was found 20 cm above the surface on one of the perches. Behavior during oviposition 0.00 4 was not observed. The following section is de 0.00 rived from observations ofthis clutch only. Paternal Care. The male remained on the sa moves to one si de ( either me perch, mostly resting on the eggs, as shown in half of the female, raises figure 1, for the whole period of embryological and extrudes the penis, in development. Only once or twice a day the male vagina. The pair remains descended to the water for periods of 2 to 35 25 minutes. minutes, and climbed back to moisten the eggs. ' the pairs could altemate This was performed by inserting the proboscis and "standing together" for into the spaces between the eggs. The male performed "stroking" only would assume a threatening position when ..,.... a••vu" was observed only approached closer than 15 or 20 cm (by my hand, under water ( see for instance ), apparently trying to grab the "aggressor" with his fore legs. Even when in the , the pair could altemate water, the male would quickly climb back to the and "mounting" oi "stan clutch and "defend" it when the lab door opened, to four hours. more than 5 meters away from the tank. this sequence of beha The female was kept in the same tank but was .,.,.. t .... leve! and always at never seen on the clutch. Only once, she tried to FIGURE l. Male of Lethocerus co/ossicus brooding a clutch of two consecutive nights. In climb the perch and the male stood between her eggs. Scale bar = 5 cm. • 10Wlltinll!:", the female clim and the clutch blocking her way up. They re one of the perches, to a mained touching each other's head for more than species that perform exclusive mal e parental care the surface, with the mal e two hours until the female went back to the be long to this family (Smith and Larsen, 1993; facing down and the water. Smith, 1997). Therefore, a comparative approach of"mounting", "copu After eight days, six nymphs hatched out ofthe ofbelostomatid species may provide cues on the "stroking" and lasting 58 eggs and the male remained there for another evolution of such behavior. The courtship of L. and "descending" to the day. The female had been fed during this time, colossicus closely resembles that of other belos from three to eight just after the eggs hatched she was dissected and tomatids such as L. cordofanus (Tawflk, 1969, back up, to another found to contain 34 mature eggs. then named L. niloticus) and L. deyrollei (lchi "copulation". "Descen kawa, 1989). It also shares behavioral pattems "copulation" in all eight DISCUSSION with species of other belostomatid genera; males hours; after this, there Belostomatids represent a particularly interes- of Abedus herberti (Smith, 1979a), A. indentatus ting taxon given that the great majority of insect (Kraus, 1989b ), Belostoma oxyurum (Schnak et 165 Macías-Ordóñez: Reproduction and population ecology ofLethocerus colossicus al., 1990),pyp!onychusgrassei(Bottger, 1974) the genus, and is probably a plesiomorphic be- around 10% of the females in and Hydrocyrus columbiae (Kopelke, 1982) per- havior relative to back brooding in other genera pulation were gravid. This woul form a "pumping display" during courtship, and of belostomatids (Smith, 1997). rational sex ratio (Emlen and O as part of their egg back-brooding behavioral re- Smith ( 1997) suggested that large belostomatid ward males unless non-gravid fe pertory (see Smith, 1997). Such behavior resem- eggs might have survived desiccation if laid on xually receptive, accepted by a m¡ bies, and is probably homologous to, the "display the splash zone at sorne point prior to the evo- of storing sperm. One female cont pumping" behavior described here for L. ca- lution ofparental care, to take advantage ofhigh mature eggs mated in the labora lossicus. The same pattern is described, and re- oxygen concentration in air. One clutch in this fulfilling the first two conditions. ferred toas "calls", by Ichikawa (1989) in L. dey- studymaintained parallel to the water interface so has been shown in A. herberti ( rollei. Smith ( 1979a) and Kraus ( 1989b) ha ve as al! the eggs hada submerged andan emergent and suggested in L. maximus ( shown thatA. herberti andA. indentatus females, section hatched unattended (11 out of 33 eggs), Thus, even though adult sex rati< respectively, are attracted to waves produced by supporting the idea that parental care might have sed, operational sex ratio of disi the pumping mal e during courtship; this response been selected first to water clutches laid abo ve adults may be mal e biased. Adult~ has not been shown for Lethocerus species, but water leve! to avoid risk of drowning or desicca- seem to be sexually inactive irru observations made in this study suggest such tion due to water leve! changes. Selection for the final molt (Ichikawa, persc possibility. Lethocerus seems to be the basal aggressive defense of clutches would enhance cation). On the other hand, ' group of the family (China, 1955; Lauck and further reproductive success ofbrooding indivi- suggests that adults of L. maxi. Menke, 1961; Mahner, 1993), therefore a beha- duals. The "enhanced fecundity hypothesis" already mated when captured on vior originally used as a sex cal! in lethocerinae ( Graul, 1973; E m! en, 1973) has be en proposed Adults from the cenote not onl: substrate brooders was probably adopted by be- (Smith, 1997) as an explanation for the fact that parts more often, but a cover of d1 lostomatinae back brooders to pro vide develop- the mal e instead of the female remains with the the wings, never found on flying ¡ mental conditions for eggs (see Smith, 1976). clutcth since it may be less costly for the maJe to dent in many cases. This sugge U pon attracting a female, "stroking" seems to be give up foraging opportunities while brooding adults are older than flying adult~ a form of mal e pre-copulatory courtship aimed to (provided he has sorne certainty of paternity and colossicus adults probably do no stimulate female receptivity to copulate. opportunity for additional mating) than for the they have found a suitable and pe1 Unlike previously described substrate brooders female because her gamete production depends for feeding and reproduction. Thü in the genus, L. colossicus seems to spend most on finding prey to produce a new egg load. The ted by Cullen ( 1969) for L. maxl ofthe brooding day time out ofthe water, cove- mother ofthe clutch brooded by the maJe in this species found in more seasonal 1 ring the clutch (figure 1), and doing short incur- study (fed ad libitum and sacrificed at the time of medius (Smith and Larsen, 1993; sions to get water to moisten the eggs. L. medius egg hatching) was found to contain a fui! clutch canus (DuBois and Rackouski, 1~ and L. deyrollei, on the contrary, spend most of ofmature eggs. gated to move from one place to the day time under water, they may come out fre- The kind ofsexual dimorphism described for L. produce and over winter. Species quently to moisten the eggs, but return to the wa- colossicus has been found in L. deyrollei (lchi- dius, whose distribution extends s ter short after (Ichikawa, 1990; Smith and Lar- kawa, 1990). One common hypothesis for the laps wiih that of L. colossicus in sen, 1993 ). L. deyrollei, however, spends most of presence of larger females is a sex specific ad- xico, might show different dispen thenightabovewaterneartheclutch,probablyas vantage in allowing the development ofa larger different populations depending e a strategy to avoid detection by infanticida! fe- clutch of eggs ( or storage of larger eggs ); espe- lity of the area. males (Ichikawa, 1995). Clutch brooding on cially when mating opportunities may be limited At the study site, around two 1 emergent substrate has been found in al! three dueto low densities and sex ratios bias (as is the could be collected injusta few h1 species ofthe genus Lethocerus in which broo- case in L. colossicus). lights of the research station ding has been observed (L. deyro/lei, Ichikawa, Few estimations of sex ratio have been made N evertheless, the study pond with 1988; L. medius, Smith and Larsen, 1993; and L. for belostomatids, but they point to a female ce of about 45 meters was suppor colossicus, this study), thus substrate brooding is biased sex ratio (Chickering, 1932; Kraus, ted population of less than 20 adt probably common to all or most ofthe species of 1989a). In this study, it was estimated that only extremely hard to find in water in 166 ------,------
Folia Entamo/. Mex., 42(2) (2003)
is probably a plesiomórphic be around 10% of the females in the flying po- swamp surrounding the station although early back brooding in other genera pulation were gravid. This would bias the ope- instars were occasionally found. The great num- (Smith, 1997). rational sex ratio (Emlen and Oring, 1977) to- bers collected under lights were most probably tsuggf~stedthat large belostomatid ward males unless non-gravid females were se- coming from the mangrove swamp as this is the survived desiccation if laid on xually receptive, accepted by a mal e, and capable only suitable habitat for belostomatids within 1O at sorne point prior to the evo of storing sperm. One female containing only two km. E ven assuming they could fly from the in- care, to take advantage ofhigh mature eggs mated in the laboratory, therefore land cenotes, the area ofwater they represent in in air. One clutch in this fulfilling the first two conditions. Sperm storage the region is between two and three orders of to the water interface so has been shown in A. herberti (Smith, 1979b) magnitude smaller. lnsects of this genus are a submerged and an emergent and suggested in L. maximus (Cullen, 1969). usually seen by local people only when attracted unattended (11 out of 3 3 eggs ), Thus, even though adult sex ratio is female bia- by lights but rarely in water. All ofthis suggests that parental care might ha ve sed, operational sex ratio of dispersing (flying) that artificial lights concentrate adults from ex- to water clutches laid above adults may be mal e biased. Adults of L. deyrollei tensive areas. Bowden ( 1964) and Cullen ( 1969) risk of drowning or desicca seem to be sexually inactive immediately after suggested that belostomatids may use the moon level changes. Selection for the final molt (lchikawa, personal communi- reflection on water as a cue to find suitable ha: of clutches would enhance cation). On the other hand, Cullen (1969) bitat. The latter author also suggested that opti- success ofbrooding indivi suggests that adults of L. maximus may have mal climatic conditions for flight, such as high lh~mcf~d fecundity hypothesis" already mated when captured on light traps. humidity or low pressure prior to heavy rainfall, 1973) has been proposed Adults from the cenote not only were missing might be sensed by belostomatids. This suggests an explanation for the fact that parts more often, but a cover of dirt and algae on that these low-density predators may be specially of the female remains with the the wings, never found on flying adults, was evi- sensitive to urban development by means oflight be less costly for the mal e to dent in many cases. This suggests that cenote disorientation. opportunities while brooding adults are older than flying adults. Therefore, L. If development of instars recorded in the labo- sorne certainty of patemity and colossicus adults probably do not disperse once ratory (obtained from an unattended clutch) for I!Kiditíonal mating) than for the they have found a suitable and permanent habitat L. colossicus resembles that in the field (instars 1 gamete production depends for feeding and reproduction. This is also sugges- of L. americanus molt into stage 11 even if not produce a new egg load. The ted by Cullen (1969) for L. maximus, however, fed, Macías-Ordóñez, unpublished), observation brooded by the mal e in this species found in more seasonal habitats like L. of instars 1 and 11 in the cenote population reveal and sacrificed at the time of medius (Smith and Larsen, 1993) and L. ameri- that up to eight clutches of eggs hatched during found to contain a full clutch canus (DuBois and Rackouski, 1992) seem obli- the period of the study. Even if instar duration gated to move from one place to another to re- were different in the wild, it is still clear that this dimorphism described for L. produce and over winter. Species such as L. me- popuh:ttion was reproducing continuously found in L. deyrollei (lchi dius, whose distribution extends south and over- throughout the study period. However, despite common hypothes~s for the laps wiih that of L. colossicus in Southeast Me- intensive searching around the days when eggs females is a sex specific ad xico, might show different dispersion pattems in and brooding males must have been present ba- the development of a larger different populations depending on the seasona- sed on instar records, neither egg clutches, or storage of larger eggs); espe lity of the area. courting, or brooding males were ever observed. opportunities may be limited At the study si te, around two hundred adults Thus, sexual behavior is extremely hard to obser- and sex ratios bias (as is the could be collected injusta few hours, under the ve in natural conditions, at least in populations ). lights of the research station in one night. inhabiting water surrounded by abundant vegeta- of sex ratio ha ve been made Nevertheless, the study pond with a circumferen- tion (the most detailed field observation in the but they point to a female ce of about 45 meters was supporting an estima- genus has been made by Smith & Larsen, 1993, (Chickering, 1932; Kraus, ted population of less than 20 adults. They were in desert ponds with almost no vegetation). E ven it was estimated that only extremely hard to find in water in the mangrove though belostomatid behavior is hard to study in 167 Macías-Ordóñez: Reproduction and population ecology ofLethocerus colossicus
the field, an effort must be maintained along this maJe in Lethocerus deyrollei Vuillefroy (Heteroptera: Be line and, along with demographic data and stu lostomatidae). Journal ofEthology, 7(2): 113-117. ICHIKA w A, N. 1990. Egg mass destroying behavior of the fe dies in captivity, will allow us to better unders mal e giant water bug Lethocerus deyrollei Vuillefroy (He COLECTA Y EVALU tand the reproductive strategies of this peculiar teroptera: Belostomatidae ). Journal ofEthology, 8( 1): 5-11. PARA EL CONTROL insect group. ICHIKA w A, N. 1995. Mal e counterstrategy against infanticide (E ofthe female giant water bug Lethocerus deyrollei (Hemi
ptera: Belostomatidae ). Jo urna/ of Insect Behavior, 8(2): 2 ACKNOWLEDGEMENTS 181-188. JAIME RUIZ VEGA , TE• 1 am grateful to the people at the "Puerto Morelos" Research KOPELKE, J.P. 1982. Brutpflegende rauber- die Belostoma Station, the support from ICMyL(UNAM), DGAP A (UNAM) tidae. Nature und Museum, 112(1): 1-14. and the group of Evolutionary Ecology (ICMyLIUNAM) KRAUS, W.F. 1989a. Is maJe back space limiting? An inves 'CIIDIR OAXACA, !Pfl under direction ofC. García. 1 also received help from O. Ca tigation into the reproductive demography ofthe giant water 1University of nul, G. Chavarría, M. Lara, the Montoya family, C. Padilla 4 bug, Abedus indentatus (Heteroptera: Belostomatidae). Univers~ty of Ar and F.J. Pizaña. Suggestions on early stages ofthis work were Journal of!nsect Behavior, 2(5): 623-648. made by C. Cordero, H. Drummond and C. Macias. Bob KRAUS, W.F. 1989b. Surface wave communication during Smith and Murray ltzkowitz made useful suggestions on early courtship in the giant water bug, Abedus indentatus. Journal Ruiz-Vega, J., T. Aquino-Bolaños, 1 drafts of this manuscript. Two anonymous reviewers greatly ofthe Kansas Entomological Society, 62(3): 316-328. el control de gallinas ciegas PhylloJ improved the manuscript. LAUCK D .R. ANDA. S. MENKE. 1961. The higher classification ofthe Belostomatidae (Hemiptera, Belostomatidae ). Annals RESUMEN. Durante el verano-otoño d REFERENCES CITED ofthe Entomological Society ofAmerica, 54: 644-57. de Oaxaca para el aislamiento de ne BEGON, M. 1979. lnvestigating Animal Abundance: Capture MAHNER, M. 1993. Systema cryptoceratorum phylogeneticum muestras positivas con un 8.9 %, sig recapturefor Biologists. University Park Press, Baltimore, (Insecta, Heteroptera). Zoologica, 143(1): 1-302. regiones mas limitativas por humedac 97 pp. SCHNAK, J.A., DOM!Zl, E .A., YA. L. ESTÉVEZ. 1990. Compor En las regiones extremadamente cál BOTTGER, K. 1974. Zur Biologie von Sphaerodema grassei tamiento reproductivo de Be los toma oxyurum (Hemiptera, número de muestras positivas se obl ghesquieri Archives in Hydrobiology, 71(1): 100-122. Belostomatidae ). Revista de la Sociedad Entomológica Ar incluyendo zonas de riego y de clima BOWDEN, J. 1964. The relation of activity of two species of gentina, 48(1): 121-128. otro en La Sierra Sur (Colecta 10 Belostomatidae to rainfall and moonlight in Ghana (He SIEGEL, S. AND N .J. CASTELLAN, N .J. 1988. Nonparamet¡ic Heterorhabditis sp .. respectivamente miptera: Heteroptera). Journal oftheEntomological Society statistics for the Behavioral Sciences. 2nd. Edition. carpocapsae Weiser (cepa ALL) y S. ¡ ofSouth Africa, 26(2): 293-301. McGraw-Hill, New York, 399 pp. variaron de 146 a 528 nemátodos po1 CHICKERING, A.M. 1932. Spermatogenesis in the Belostoma SMITH, R. L. 1976. MaJe brooding behavior of the water bug población variaron de 369 a 3910 nem tidae. III. The Chromosomes in the maJe germ cells of Le Abedus herberti (Hemiptera Belostomatidae ). Annals ofthe altos valores podrían indicar una baja thocerus from New Orleans, Louisiana. Papers ofthe Mi Entomologica/ Society of Ame rica, 69( 4 ): 740-7. mas muestreos en el futuro, especialr chigan Academy ofSciences, Arts and Letters, 15: 357-361. SMITH, R. L. 1979a. Paternity assurance and altered roles in PALABRAS CLAVE: Plagas del suelo, ' CHINA, W.E. 1955. The evolution ofthe water bugs. Natural the mating behavior of a giant water bug, Abedus herberti · Sciences, India Bulle/in, 7(1): 91-103. (Heteroptera: Belostomatidae). Animal Behavior, 27(3): Ruiz-\ega, J., T. Aquino-Bolaños CULLEN, M.J. 1969. The biology of giant water bugs (He 716-725. nematodes for wh1te grub Phyllopl miptera: Belostomatidae) in Trinidad. Proceedings of the SMITH, R. L. 1979b. Repeated copulation and sperm prece Royal Entomo/ogica/ Society, London, (A), 44(7-9): 123- dence Paternity assurance for a maJe brooding water bug. ABSTRACT. To isolate entomopatho¡ 136. Science, 205: 1029-1031. collected in eight natural regions of C DUBOIS, R. B. AND M. L. RACKOUSKI. 1992. Seasonal drift of SMITH, R. L. 1997. Evolution ofpaternal care in the giant water positive samples (8.9 %) followed by Lethocerus americans (Hemiptera: Belostomatidae) in a bugs (Heteroptera: Belostomatidae). pp. 116-149. In: J. C. (2.7 %). Drought prone areas such as Lake Superior tributary. The Great Lakes Entomologist, CHOE AND B. l CRESPI (eds ). The Evo/u/ion of Social and dry regions such as Costa and Istn 25(2) 85-89. Behavior in Insects and Arachnids. Cambridge University in medium textured soils, with adeq EMLEN, J.M. 1973. Ecology: An Evolutionary Approach. Press, Cambridge, 541 pp. obtained, two from Cañada (Sample Addison-Wesley, Reading, 493 pp. SM!TH, R. L. ANDE. LARSEN. 1993. Egg attendance and broo Steinernemafeltiae Filepjev Steiner~ EMLEN, S.T. AND L.W. ÜRING. 1977. Ecology, sexual ding by males of the giant water bug Lethocerus medius nematodes per white grub for Steine selection, and the evolution of mating systems. Science, (Guerin) in the fíe Id (Heteroptera: Belostomatidae ). Journal nematodes per larva for the promisin 197(4300): 215-223. ojlnsect Behavior, 6(1): 93-106. 391 O nematodes/larva, the highest C( GRAUL, W.D. 1973. Breeding biology ofthe mountain plover. T AWFIK, M.F.S. 1969. The life-history ofthe giant water-bug, nematodes may imply a low pathoge¡ The Wilson Bulle/in, 7( 1): 2-31. Lethocerus ni/oticus Stael. Bulle/in of the Entomologica/ out more surveys in the future, espec ICHIKAWA, N. 1988. MaJe brooding behavior of giant water Society ofEgypt, 53: 299-310. KEY WORDS: Soil-dwelling insect pe bug Lethocerus deyrollei Vuillefroy (Hemiptera: Belosto matidae). Journal ofEthology, 6(2): 121-127. Recibido: 20 de marzo del 2002 ICHIKAWA, N. 1989. Repeated copulations benefit ofthe fe- Aceptado: 2 de abril del 2003. 1 168 Proyecto financiado por UCMEXU