AMERICAN MUSEUM Novitates PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, N.Y. 10024 Number 3065, 17 pp., 22 figures June 10, 1993

Natural History and Systematics of Symbionts (Araneae; Hemiptera; Diptera) Inhabiting Webs of the Tengella radiata (Araneae, )

WILLIAM G. EBERHARD,' NORMAN I. PLATNICK,2 AND RANDALL T. SCHUH3

ABSTRACT

The webs of the Costa Rican tengellid spider er numbers include the theridiid spider Tengella radiata (Kulczyinski) are regularly inhab- bryantae Exline and Levi, the mysmenid ited by at least four species of arthropod symbi- Mysmenopsis dipluramigo Platnick and Shadab onts: the phorid fly Megaselia scalaris Loew; the and Maymena rica Platnick, new species, and the plokiophilid bug Lipokophila eberhardi Schuh, new plokiophilid bug Lipokophila tengella Schuh, new species; the uloborid spiderPhiloponella vicina (O. species. The behaviors ofthe symbionts and hosts, P.-Cambridge); and the mysmenid spider Mys- and the interactions among them (which include menopsis tengellacompa Platnick, new species. contest competition, parasitism, , and Other found in Tengella webs in small- commensalism) are described.

' Staff Scientist, Smithsonian Tropical Research Institute; Professor, Escuela de Biologia, Universidad de Costa Rica, Ciudad Universitaria, Costa Rica. 2Chairman and Curator, Department of Entomology, American Museum of Natural History; Adjunct Professor, Department of Biology, City College, City University of New York; Adjunct Professor, Department of Entomology, Cornell University. 3Curator, Department of Entomology, American Museum of Natural History; Adjunct Professor, Department of Biology, City College, City University of New York; Adjunct Professor, Department of Entomology, Cornell Uni- versity.

Copyright © American Museum of Natural History 1993 ISSN 0003-0082 / Price $2.00 2 AMERICAN MUSEUM NOVITATES NO. 3065

INTRODUCTION The webs oflarge spiders, such as the orb- Other arthropod species that inhabit Ten- weavers Nephila and Cyrtophora, and some gella webs but have been collected in smaller diplurids, psechrids, and social theridiids, are numbers include the theridiid spider Argy- known to harbor a number of species of rel- rodes bryantae Exline and Levi, the mys- atively small kleptoparasites such as ulobor- menid spiders Mysmenopsis dipluramigo id, theridiid, pholcid, and mysmenid spiders, Platnick and Shadab and Maymena rica Plat- chloropid and drosophilid flies, and others nick, new species, and the plokiophilid bug (Exline and Levi, 1962; Thornhill, 1975; Lipokophila tengella Schuh, new species. Vollrath, 1976, 1979a, b, c; Robinson and We thank Drs. F. C. Thompson and R. Robinson, 1977; Robinson and Lubin, 1979; Peterson ofthe Systematic Entomology Lab- Eberhard, 1980; Nyffeler and Benz, 1980; oratory, Department of Agri- Rypstra, 1981; Sivinski and Stowe, 1981; Ta- culture, for identifying the phorid flies. In naka, 1984; Griswold, 1985; Nentwig, 1985; addition to material in the American Mu- Sivinski, 1985; Forster and Murphy, 1986; seum of Natural History (AMNH), speci- Whitehouse, 1986; Baert and Murphy, 1987; mens were supplied by Mr. Darrell Ubick of Coyle and Meigs, 1989, 1992; Coyle et al., the California Academy of Sciences (CDU), 1991). In general, these species take advan- Mr. John A. Murphy of Hampton, England tage ofthe fact that the large spiders often do (JAM), and Dr. H. W. Levi of the Museum not respond to the presence of very small of Comparative Zoology, Harvard Univer- in their webs (presumably thus sity (MCZ). Help with illustrations was pro- avoiding expenditures of energy that are un- vided by Dr. Mohammad U. Shadab likely to significantly enhance prey intake). (AMNH). We thank Drs. Jonathan A. Cod- Some symbionts capture small prey that fall dington of the National Museum of Natural into the web and are undetected or ignored History and Frederick A. Coyle of Western by the owner, and some feed directly from Carolina University for helpful comments on prey being consumed by the owner. a draft of the manuscript. This paper describes still another situation of this sort, with the unusual complication that four rather than one species ofinsect and NATURAL HISTORY spider regularly inhabit webs of the host, METHODS Tengella radiata (Kulczy'nski). These include a phorid fly, a plokiophilid bug, and repre- Most of the behavioral observations were sentatives of two other spider families (Ulo- made on animals kept on Tengella webs in boridae and ). The interactions 22 x 30 x 10 cm plastic containers with glass among these species are complex, and include tops. This permitted observations of details contest competition, parasitism, predation, of behavior inside the tubular retreats that and commensalism. Two of the species, the would otherwise have been difficult or im- mysmenid spider Mysmenopsis tengellacom- possible. Some additional observations were pa and the plokiophilid bug Lipokophila made in the field near San Antonio de Escazu, eberhardi, are described below as new by the Costa Rica. Counts of symbionts were made second and third authors, respectively. by collecting entire webs, including retreats, Fincke (1981) showed that one of the as- and carefully examining their contents. sociated species, the uloborid spider Philo- ponella vicina (0. P.-Cambridge), faculta- THE HOST tively builds its orb-webs in the mesh of Tengella radiata is an unusual spider, and threads above Tengella sheet webs, and ap- the family Tengellidae is of uncertain limits. parently prefers such websites over alterna- The association with Tengella ofsuch genera tives. Those spiders associated as Calamistrula, Lauricius, Liocranoides, and with Tengella fed more often and disap- Zorocrates proposed by Lehtinen (1967) re- peared less often from their websites than did mains unsupported by synapomorphies, but nonassociated conspecifics. Griswold (cited in Coddington and Levi, 1993 EBERHARD ET AL.: TENGELLA SYMBIONTS 3

Fig. 1. Webs of mature Tengella radiata females. Lateral (a) and end-on (b) views of a newly built web (probably built the preceding evening). Lateral view (c) of an older web, with close-up (d) of outer edge of sheet. The tunnel retreat is at the right in (a) and (c). Arrow in (c) marks long, sagging sticky line. Note also sparse mesh and orbs ofPhiloponella vicina which are present in (c) but nearly completely lacking in (a) and (b). Scale bar = 10 cm in (a), (b), and (c), 2 cm in (d).

1991) has treated tengellids as the sister group (Wolff, 1977; W. Eberhard and M. Santana, of the classical Lycosoidea. Only three spe- unpublished data). Despite its obvious suc- cies of Tengella are known, and two of those cess in varied habitats, however, T. radiata are apparently very rare, being represented is unknown outside Costa Rica. In Panama by a total of four specimens from , and further south, similar webs in similar Guatemala, and "South America" (Wolff, sites are constructed by mygalomorph spi- 1977). Tengella radiata, however, is ex- ders of the family Dipluridae. What factors tremely common in a wide variety ofhabitats limit the ranges of these apparently ecologi- in Costa Rica, ranging from elevations of cally equivalent groups remain unknown. about 50 m in tropical rain forest up to at The web of T. radiata is generally a large, least 1500 m in secondary growth in and flat sheet turned up at the edges, narrowing around coffee fields in the Valle Central to a tube at the rear, protected side (fig. 1). 4 AMERICAN MUSEUM NOVITATES NO. 3065

During the day, the spider, which is about 2 BEHAVIOR AWAY FROM cm long, is usually found in the tube, whereas THE TENGELLA RETREAT at night it rests at the mouth or on the upper surface of the sheet near the entrance. Con- Both Mysmenopsis tengellacompa and Li- trary to the report of Fincke (1981), spiders pokophila eberhardi were frequently seen on will often attack prey during the day. There the sheet of the host's web. Both walked ei- is a meshwork of threads of variable density ther on top of or under the sheet without and extension above the sheet, and long, sag- apparent difficulty. Most movements were ging lines of cribellum (sticky) silk are often relatively leisurely, but M. tengellacompa in- attached to the meshwork near the edges of dividuals occasionally made brief, quick runs, the sheet (fig. 1). In a newly built web, the especially when fighting among themselves mesh above the sheet was reduced, and there near prey. In both cases, and probably es- were no lines of cribellum silk. When prey pecially in the case of the bug, older individ- falls onto the sheet, the spider usually rushes uals (both males and females) were more like- out, seizes it with its chelicerae, and rushes ly to be found on the sheet away from the back to the tube, where it finishes subduing tube than were younger ones. the prey and feeds. Both ofthese species attacked small insects (e.g., ants about 2 mm long) dropped onto the web. The spiders usually moved to the THE SYMBIONTS prey in a series of short bursts of running or Lipokophila, Mysmenopsis, and Philopo- walking that were interspersed with short nella symbionts were present in appreciable pauses. They often reoriented and moved numbers in the webs of larger Tengella at more directly toward the prey after such both Finca La Selva (elev. 100 m, near Puerto pauses, and in general gave the impression Viejo, in Heredia province) and San Antonio of having only an imprecise ability to orient de Escazu (elev. 1300-1400 m, in San Jose toward prey struggling on the sheet. Attacks province). The phorid fly Megaselia scalaris by M. tengellacompa were simple, with the Loew was uncommon in San Antonio, and spider running or walking toward the prey, not seen at La Selva. At another highland site usually on the undersurface of the sheet, and (Monteverde, elev. approximately 1200 m, biting it through the sheet. When the prey in Puntarenas province), an additional sym- became more or less immobile, the spider biont, Argyrodes bryantae Exline and Levi, pulled it through the sheet by cutting a small was also common, along with species of Li- hole, and carried it away. The spiders did not pokophila and Mysmenopsis (J. Crawford, usually wrap their prey either before or after unpublished data). immobilizing it, but in one case a spider, after At all sites symbionts were usually absent having had a difficult time pulling the prey from the webs ofearly instar nymphs of Ten- free from the sheet (due to another spider gella. In a collection of 25 webs of adult fe- holding it from the other side of the sheet), male and penultimate nymphs of Tengella wrapped the prey with slow alternate move- made on 10 Dec. 1982 at La Selva, there were ments of its legs IV. an average of 5.8±6.0 Lipokophila bugs On one occasion (in the field), a spider at- (range 0-20) and 2.0±2.2 Mysmenopsis spi- tacked and fed on an intermediate-sized ders (range 0-6); these counts are conserva- nymph of L. eberhardi that was feeding with tive, since the considerable quantities of de- several other bugs on a dead ant that had tritus in some webs made it difficult to find been killed but then rejected by the Tengella. the symbionts. There was a strong positive Specimens of M. tengellacompa usually ei- correlation between the numbers ofbugs and ther fled from the vicinity of prey trapped in spiders (linear correlation coefficient r = 0.69, the sheet that were larger than themselves, or p = 0.00013); possibly this was due to older approached only part way and then retreated. Tengella webs having accumulated larger Both male and female spiders attacked prey, numbers ofsymbionts. All behavioral obser- but females that were carrying egg sacs (held vations reported below were made on spec- with one leg IV on a short line from the spin- imens from San Antonio de Escazu. nerets, in the manner of some theridiids and 1993 EBERHARD ET AL.: TENGELLA SYMBIONTS 5 nesticids-see, e.g., Bristowe, 1958) did not its struggle with the Tengella, and again the respond to prey except to move away. M. tengellacompa fed on this overlooked food Sometimes more than one M. tengellacom- item. pa responded to the same prey, and in these M. tengellacompa also chased L. eberhardi cases aggressive interactions often ensued bugs that approached when the spiders were (aggression was also seen once around a drop attacking or feeding on prey. The bugs usually of water on the web from which one of the retreated, but on one occasion the bug re- spiders had been drinking). When the two turned and inserted its proboscis into the prey spiders were of unequal sizes, the larger one for 30-60 sec while the spider chased off a generally chased the smaller one from the second spider. On another occasion, the bug vicinity of the prey. When spiders of ap- fed from below the sheet while the spider fed proximately equal size fought, they met head- on the prey from above. The bugs often re- to-head and interlocked legs I and perhaps turned persistently, usually each time from a also legs II. In some cases they remained more different angle than before, with the eventual or less immobile in this position for several result in some cases of having the prey more seconds before one withdrew a little and the or less between themselves and the spider. other then chased it away. When the prey was When the prey was large enough, this some- large compared to the spiders, several often times resulted in both the spider and bug fed on it simultaneously, with the smaller feeding from the same prey. It appeared from ones positioned so that the prey was between the bugs' behavior that they may have been themselves and the larger spiders. Most spi- able to distinguish the general area where a ders were on the underside ofthe sheet; those spider and its prey were from a distance, but on the other side from an attacker were less that they had to touch the prey with an an- susceptible to being chased. On some occa- tenna in order to guide the insertion of their sions, a smaller spider on the other side of probosces. Occasionally an adult bug did not the sheet fed, despite apparent attempts to run from an approaching M. tengellacompa, chase it away, until the larger one finally made but instead flattened itself to the sheet and a hole in the sheet to pull the prey through. remained immobile while the spider arrived. Once a small prey was freed from the sheet, In some cases the spider tapped the bug with the spider that carried it always moved away its legs and pedipalps, and it was clear that at least a few millimeters, and extended ag- the spider could have attacked the bug, but gressive interactions ceased, as the spider car- did not. rying the prey simply moved away when oth- These were not the only species to squabble ers approached. over small prey on the sheet. On two occa- On two occasions when a larger prey was sions the relatively huge Tengella came onto dropped onto the sheet, a large M. tengella- the sheet to seize a Drosophila-size prey that compa that had been resting near the mouth M. tengellacompa spiders were about to at- of the tube retreat ran out under the sheet to tack. And on one occasion, a Philoponella wander more or less in the area of the sheet that had an orb whose frame lines were close where the Tengella had attacked the prey, to the edge of the sheet came to the edge of stopping briefly at pieces ofdebris it encoun- its web and attacked a prey that was near the tered there. On other occasions, the rush of edge of the sheet, and then carried it back to the Tengella onto the sheet to attack prey its hub. apparently stimulated several M. tengella- The L. eberhardi bugs also attacked prey compa to a burst of less directed movement. by themselves. They generally approached In two cases this type ofbehavior resulted in slowly, and probed repeatedly with their ex- a meal for the M. tengellacompa. In one case tended probosces. When a bug was below the the Tengella had been feeding on another sheet, it inserted its proboscis through the prey, and when it initiated its attack on the sheet to reach the prey. The bugs were quite second prey it laid the first on the sheet, where cautious, and often made repeated approach- the M. tengellacompa began feeding on it from es without inserting the proboscis. In one case below. In the second case one of the prey's an adult bug made a series of unsuccessful legs became detached from its body during approaches to a struggling prey on the top of 6 AMERICAN MUSEUM NOVITATES NO. 3065 the sheet, then moved through a hole in the the tunnel. Their approaches to the prey were sheet to the underside and approached much clearly cautious, and it appeared that they less cautiously and succeeded in inserting its were stimulated to move by movement on proboscis, suggesting an ability to take ad- the part of the Tengella, a tactic also seen in vantage ofthe protection offered by the sheet. parasitic wasps attempting to attack eggs de- Both the spiders and the bugs also fed on fended by female pentatomid bugs (Eber- inanimate objects. On several occasions bugs hard, 1975). The larger spiders (all the adults inserted their probosces into a discarded prey observed) differed in that they never moved package that had fallen onto the sheet from inside the retreat. They remained instead on a Philoponella web above; in some of these the retreat's outer surface, and attempted to cases the bug's proboscis remained in the bite the prey that the Tengella was feeding package for a minute or more, suggesting that on where it contacted the tunnel wall. It was the bug was actually extracting nourishment clear on several occasions that an M. tengel- rather than just testing. In one case (in cap- lacompa had been successful in doing this, as tivity), a Tengella constructed an egg sac when the Tengella began to move its prey it above the web's sheet, but its eggs failed to came loose with a jerk from the point on the adhere to the sac and fell onto the sheet in a tunnel wall where the M. tengellacompa was wet mass, where bugs, Mysmenopsis, and the biting. female Tengella all fed on it. No aggressive interactions were observed among symbionts within the retreat. Occa- sionly large M. tengellacompa on the outside BEHAVIOR WITHIN surface THE TENGELLA RETREAT squabbled over access to a point where the prey contacted the wall of the retreat. Three ofthe symbiont species (all but Phil- Sometimes it seemed that a Tengella sensed oponella and Argyrodes) were often found near the movement of M. tengellacompa on the the tunnel-like retreat of the Tengella, and other side ofthe tunnel wall. It responded by observations in captivity showed that they tapping the sheet carefully with its palps where fed there on prey captured by Tengella. The the other spiders were moving, and by re- simplest behavior was that ofthe L. eberhardi peatedly shifting the prey, setting it down, bugs and Megaselia flies. In both cases, the wrapping it, and picking it up again, and also insects walked slowly toward the spider, and by moving back and forth within the tunnel. climbed directly onto the prey that it held in Such movements of the prey often (but not its chelicerae. Once on the prey, they applied always) caused the bugs that were on it to their mouthparts to it, and within several decamp. Only infrequently did a Tengella ap- minutes their abdomens were usually dis- pear to sense the presence of other species tinctly swollen. After obtaining a meal, the inside the tunnel with it, or on the prey, but insects dropped from the prey onto the floor on several occasions spiders used a leg or palp of the tunnel. The flies usually stayed near in an apparent attempt to brush one of them the tunnel even when not feeding (they were offthe prey. The Tengella either quickly with- found in spiders' retreats in the field), but the drew its leg or brushed it with another when bugs, as noted above, were also commonly a bug or M. tengellacompa touched it. found out on the sheet. When the Tengella At night Tengella fed on prey near the tun- rushed out, attacked a prey, and then rushed nel mouth, and stilted high on its legs as it back to its retreat, the bugs on the sheet gen- did so. This stilting may represent a further erally began moving slowly but directly to- defense against the kleptoparasites, making ward the tunnel. The nymphs ofLipokophila it more difficult for them to climb onto the are bright red, and the "mites" noted by prey and to bite the prey from the other side Fincke (1981) on the prey of Tengella in the of the web. The Tengella never made any retreat were probably these bugs. more forceful defensive responses to any of The behavior ofthe M. tengellacompa spi- the parasites, despite the fact that they were ders was more complex. Younger juveniles able to locate and attack such small prey as behaved much as did the flies and bugs, Drosophila flies and small calliphorid larvae climbing slowly directly onto the prey inside on their webs. One observation suggested that 1 993 EBERHARD ET AL.: TENGELLA SYMBIONTS 7 this lack of responsiveness by the Tengella This movement may serve as a defense against may be due to previous unpleasant experi- egg parasites; similar movements are made ences rather than an inability to sense the by theridiid spiders defending against sce- presence of the parasites. When a prey that lionid wasp egg parasites (Valerio, 1984). a Tengella was holding in its retreat was ex- perimentally poked with a small stick, a L. DISCUSSION eberhardi nymph that had been feeding there was inadvertently squashed. The spider im- The ecological relationships documented mediately dropped the prey and rushed to here are outlined in figure 2. At least three of the far edge of the web, where it remained the symbionts parasitize the host by feeding motionless, hanging over the edge, for 10-20 on prey (or digestive juices) that would oth- min. A moment after squashing the bug, a erwise have been utilized by Tengella. There pungent odor was apparent; presumably, the is also direct competition between M. ten- spider's flight was caused by the odor of the gellacompa and L. eberhardi for food, with squashed nymph. This odor may also induce the spiders attempting to sequester food from dispersal among the bugs, as the attack on a other spiders and also from the bugs. The nymph by an M. tengellacompa noted above spiders are apparently better able to subdue was immediately followed by the dispersal of prey than the bugs, and feeding by the bugs all the bugs that had been feeding on the same at prey captured by M. tengellacompa can be prey, with only a gradual return later. considered parasitism (or, in this case, hy- perparasitism). In addition, the M. tengel- lacompa at least occasionally prey on the bugs. OTHER BEHAVIORS The relationship ofPhiloponella to the oth- Mating. One pair of Lipokophila was seen er symbionts is not as intimate. The discard- copulating while they were on a prey held in ed prey packages of these spiders may rep- the chelicerae of a Tengella. After several resent a portion of the diet of the bugs, and minutes, the spider brushed them off, and the spiders may occasionally take prey that they separated. When several adults were in would have been captured by one ofthe sym- close proximity, as when near a large prey, bionts or by the Tengella. It seems very un- males made short, quick dashes in apparent likely that the Philoponella capture the bugs attempts to mount other individuals. The with any frequency, as Fincke (1981) sug- other individuals either avoided the dashes gested might happen. In general the biological or quickly ran out from under the males. impact of Philoponella on the other species Two mating pairs of Mysmenopsis were is probably of minor importance. observed. In both cases, the spiders were fac- The puzzling lack ofresponsiveness by the ing each other (in mating position I of Ger- Tengella to the presence of symbionts in its hardt), and each held the sheet with all its retreat and on its prey may be explained by legs. The male's legs were folded quite tightly the defensive odor of the bugs. If this is the to his body, whereas the female's legs were case, then both the flies and the Mysmenopsis somewhat more extended, and partially en- spiders may derive benefit from the presence circled the male. One palp was inserted at a ofthe bugs because the bugs' odor makes the time in the opposite side of the female (i.e., host spider less likely to attack them. the male's right palp reached across the fe- The bugs and the M. tengellacompa and male and inserted in her right epigynal open- Tengella spiders all show behavioral re- ing). Each palp was inflated repeatedly during sponses to the presence of other species in each insertion, but otherwise the spiders were the Tengella webs. The stilting and frequent nearly motionless. changes of feeding site by Tengella make it Maternal Care. Several Mysmenopsis fe- more difficult for the M. tengellacompa, par- males carried an egg sac attached to a short ticularly the larger ones, to feed on its prey. line held with one leg IV. One female with The change in M. tengellacompa feeding sites an egg sac passed her leg III repeatedly over from inside to outside the tunnel with in- the surface of the sac while she held it in the creased size, their cautious approaches inside normal position dangling from one leg IV. the tunnel, and their apparent searches in ar- 8 AMERICAN MUSEUM NOVITATES NO. 3065

Tengella radiata Chiriqui, Panama, in Museum of Comparative Zoology, not examined).

Megaselia scalaris Exline and Levi (1962) presented a descrip- Mysmenopsis tion of both sexes of this species. Unfortu- tengellacompa nately, the epigynum of their only female specimen was lost before it could be illus- trated. A pair ofspecimens taken from a Ten- gella web at an elevation of 1350 m at Mon- - parasitism Lipocophila predation teverde, Puntarenas, Costa Rica (June 1986; eberhardi competition W. G. Eberhard; AMNH) allows us to present benefits here illustrations (figs. 3, 4) ofthe epigynum. Fig. 2. Possible ecological relationships among The species has been collected in both Costa the taxa discussed. Rica and Panama, but because no habitat data accompanied any of the original speci- mens, it is unknown whether the species is eas where the Tengella hadjust attacked prey restricted to Tengella webs. may all be adaptations to the behavior of Tengella. Similarly, the tendency for L. eber- FAMILY MYSMENIDAE hardi to reapproach prey defended by M. ten- gellacompa from different directions in suc- Mysmenopsis tengellacompa cessive tries, to crouch when approached by Platnick, new species an M. tengellacompa, to move from the sheet Figures 5-9 into the tunnel when Tengella captures a prey, TYPES: Male holotype taken in a web of and their less cautious attack when the sheet Tengella radiata at an elevation of 100 m at is between them and a potential prey all sug- La Selva, near Puerto Viejo, Heredia, Costa gest adaptations to interactions with other Rica (Apr. 1983; W. G. Eberhard), deposited species on Tengella webs. in AMNH. ETYMOLOGY: The specific name refers to SYSTEMATICS the lifestyle ofthese spiders as Tengella com- ARANEAE panions. FAMILY THERIDIIDAE DIAGNOSIS: This species seems most close- ly related to Mysmenopsis cymbia (Levi), Argyrodes bryantae Exline and Levi which is known only from Florida. In the Figures 3, 4 cladogram ofthe proposed by Platnick Argyrodes bryantae Exline and Levi, 1962: 172, and Shadab (1978: fig. 1), M. cymbia repre- figs. 286-288 (male holotype from Boquete, sents the sister group ofall other known Mys-

3 4

Figs. 3, 4. Argyrodes bryantae Exline and Levi, epigynum, ventral and dorsal views. 1993 EBERHARD ET AL.: TENGELLA SYMBIONTS 9

9

Figs. 5-9. Mysmenopsis tengellacompa Platnick, new species. 5. Left male palp, prolateral view. 6. Same, ventral view. 7. Same, retrolateral view. 8. Epigynum, ventral view. 9. Same, dorsal view. menopsis, and this new species agrees with outlining six pairs ofdark rectangles. Femora M. cymbia rather than its congeners in having without median dark rings; tibiae with prox- the embolus encircling the palpal bulb, a fea- imal dark spots on venter only. Clypeal height ture judged plesiomorphic because of its oc- about five times anterior median eye diam- currence in Mysmena and Maymena. The eter; pair ofconspicuously lightened oval ar- new species is united with M. cymbia by the eas present below those eyes. Femora II, III, presence ofa greatly thickened embolus found and basal one-third of IV with row of stiff only in those two species. Males of M. ten- setae retroventrally. Tibia I with strong sub- gellacompa can be distinguished by the trans- distal clasping spine, metatarsus with strong, versely oriented embolar origin (figs. 5-7), sinuous subproximal clasping spine. Palp as females by the more complex spermathecal in figures 5-7. ducts (fig. 9). FEMALE: Total length 2.70 mm. Carapace MALE: Total length 2.03 mm. Carapace 1. 14 1.18 mm long, 1.01 mm wide, 0.38 high. As mm long, 0.99 mm wide, 0.56 mm high. in male, except as follows. Clypeal height only Structure and coloration typical for genus (see about four times anterior median eye di- Platnick and Shadab, 1978: 6) except as fol- ameter; no pale areas noticeable below those lows. Pars thoracica paler medially than lat- eyes. Clasping spines absent; femur I sinuous erally. Transverse abdominal white bands but without ventral or prolateral tubercles, 10 AMERICAN MUSEUM NOVITATES NO. 3065

10 12

13

Figs. 10-13. Maymena rica Platnick, new species. 10. Left male palp, prolateral view. 11. Same, ventral view. 12. Same, retrolateral view. 13. Epigynum, dorsal view. with ventral subdistal sclerotized spot. Meta- 1100 m, cloud-rainforest transect (D. Ubick, tarsus I without spines. Epigynum as in fig- CDU), 26, 3Q; San Antonio de Escazu, June ures 8, 9. 1983, elev. 1300-1400 m (W. G. Eberhard, OTHER MATERIAL EXAMINED: Except as AMNH), 56, 5. noted, all specimens were captured in Ten- DISTRIBUTION: Known only from the webs gella webs. COSTA RICA: Heredia: La Sel- of Tengella and unidentified agelenids and va, near Puerto Viejo, Apr.-June 1982-1983, diplurids in Costa Rica. elev. 50-100 m (W. G. Eberhard, AMNH), 126, 152. Limon: 2 km W Bribri, May 17, Mysmenopsis dipluramigo 1987, elev. 100 m, moist tropical forest (D. Platnick and Shadab Ubick, CDU), 26, 22. Puntarenas: Montev- erde, Feb. 10, 1978, from diplurid web along Mysmenopsis dipluramigo Platnick and Shadab, stream (N. Moran, AMNH), 16, 42, Aug. 26, 1978: 10, figs. 22-27 (male holotype from Pipe- line Road, Canal Area, Panama, in AMNH, ex- 1983, hotel grounds (J. A. Murphy, JAM), amined). 26, 12, June 1986, elev. 1350 m, near cheese factory (W. G. Eberhard, AMNH), 26, 12, NEW RECORDS: COSTA RICA: Heredia: June 1986, elev. 1350 m, in web of uniden- La Selva, near Puerto Viejo, Mar.-Apr. 1983, tified agelenid near cheese factory (W. G. elev. 100 m, in webs of Tengella and an un- Eberhard, AMNH), 16. San Jose: Parque Na- identified ctenid (W. G. Eberhard, AMNH), cional Braulio Carillo, Apr. 28-30, 1983, elev. 36, 1 . PANAMA: Canal Area: 4 mi W Gam- 1993 EBERHARD ET AL.: TENGELLA SYMBIONTS I1I

boa, Aug. 7, 1983, lowland rainforest (R. J. 0; metatarsus III pO-1-0. Palp as in figures Raven, AMNH), 38,12; Rio Frijolita, July 4, 10-12. 1976 (L. Kirkendall, AMNH), 16. Panama: FEMALE: Total length 1.24 mm. Carapace upper Rio Maje, Bayano region, June 13, 0.59 mm long, 0.53 mm wide, 0.26 mm high. 1976, in pisaurid web (L. Kirkendall, As in male, except as follows. Chaetotaxy: AMNH), 1. femur IV dl-0-0; tibia I dl -0-0, pO-0 - 1, rO- DISTRIBUTION: Known only from the webs 0-1, without clasping spur; metatarsus I with- of Tengella and unidentified pisaurids, cten- out clasping spur. Epigynum with only slight ids, and diplurids (probably Linothele sp.; see posteromedian evagination externally, dorsal Paz, 1988) in Panama and Costa Rica. view as in figure 13. OTHER MATERIAL EXAMINED: COSTA Maymena rica Platnick, RICA: Cartago: Guyabo, near Turrialba, May new species 1981, elev. 1300 m (W. G. Eberhard, Figures 10-13 AMNH), 1Q; Tuis hilltops, Apr. 1, 1979 (J. Coddington, MCZ), 12. Heredia: West River TYPE: Male holotype and female allotype Road, OTS Station, Finca La Selva, near taken on West River Road at the Organiza- Puerto Viejo, Nov. 14-Apr. 12, 1979-1982 tion for Tropical Studies field station at Finca (J. Coddington, MCZ), 116, 132, Dec.-Mar. La Selva, near Puerto Viejo, Heredia, Costa 1978-1983, elev. 50-100 m (W. G. Eberhard, Rica (Jan. 13, 1982; J. Coddington), depos- MCZ, AMNH), 16 (penultimate), 122. Pun- ited in MCZ. tarenas: Llorona, Corcovado National Park, ETYMOLOGY: The specific name is a noun Aug. 10, 1979 (J. Coddington, MCZ), 12. San in apposition taken from the type locality. Jose: Parque Nacional Braulio Carrillo, Apr. DIAGNOSIS: This distinctive species is eas- 26-30, 1983, elev. 1100 m, cloud-rainforest ily recognized by genitalic characters. The transect (D. Ubick, CDU), 18; Rio Hondura, relatively short but complexly twisted cym- Mar. 1986, elev. 1200 m (W. G. Eberhard, bium of the male palp (figs. 10-12) is diag- AMNH), 22. nostic; the female epigynum (fig. 13) most DISTRIBUTION: Known only from Costa closely resembles that ofthe Mexican species Rica, where it occasionally inhabits the webs Maymena cascada Gertsch, but has the scler- of Tengella. otized ducts straight rather than curved. In NOTE: The web and web-building behavior both sexes, the abdomen is posteriorly flat- of this species were described (as Maymena tened, so that it appears triangular in lateral sp.) by Eberhard (1986); because specimens view, rather than rounded as in typical mem- of this species do construct a normal May- bers of the genus. mena web, their occurrence in Tengella webs MALE: Total length 1.08 mm. Carapace 0.56 may be accidental. mm long, 0.49 wide, 0.21 mm high. Structure typical for genus (see Gertsch, 1960: 30-31) HETEROPTERA except as follows. Carapace light brown, FAMILY PLOKIOPHILIDAE lightest near margins; tibiae, metatarsi, and Three species of spider-web dwelling Plo- tarsi III and IV with distal dark rings; ab- kiophilidae have previously been described domen dark gray anteriorly, with about seven from the New World: Plokiophila cubana transverse white stripes posteriorly, most an- ( and Myers, 1929) from Cuba and Li- terior stripe thickest. Ocular area protruding pokophila chinai Stys (1967), and L. stysi strongly forward, clypeal height only twice Carayon (1974), from Santa Catarina, . the anterior median eye diameter; anterior Two additional species ofLipokophila are de- lateral eyes smaller than anterior medians, scribed below from Costa Rica, both occur- not on ocular protrusion. Chaetotaxy: fem- ring in the webs of Tengella radiata, some- ora: I dl-0-0, pO-1-i, rO-O-1; II dl-0-0, pO- times in the same web. Lipokophila eberhardi 0-1, rO-O- 1; III dl -0-0; patellae I-IV dO-O- 1; is the more common of the two species and tibiae: I pO-1-0, rI -0-0 plus distal prolater- is also available from nymphs of nearly all oventral clasping spur that overlaps similar instars. sput situated proximally on metatarsus I; II In addition to the Plokiophilinae, repre- pO-1-i. rl-0-l; III dl-0-0, pO-1-0; IV dl-0- sentatives of at least three other groups of 12 AMERICAN MUSEUM NOVITATES NO. 3065

Heteroptera appear to live as commensals in one sees a large pelucid glandular body (Car- spider webs. Some Emesinae (Reduviidae) are ayon, 1974: fig. 1B), whereas the SEM reveals regularly found in webs, and many have an opening with an attenuated structure ris- modifications of the foretarsi that may rep- ing above it and directed posteriorly (fig. 20; resent adaptations for such a mode of life Carayon 1974: fig. 13). The corium in the (Wygodzinsky, 1966). abovementioned Embiophila sp. is also com- The genus Ranzovius (Miridae: Phylinae) pletely covered with corial glands but the contains seven species (Henry, 1984), all of structure ofthe openings is somewhat differ- which are apparently obligate web dwellers. ent from that found in L. eberhardi. During the course of this study Schuh ex- The male genitalic structures of Lipoko- amined specimens from Costa Rica identi- phila were described in detail by Stys (1967) fiable as Ranzovius crinitus (Distant) and an- for L. chinai and for L. stysi by Carayon other unidentifiable species represented only (1974). The structure and location ofthe cop- by females, all from the webs of Anelosimus ulatory tubes for both those species was de- (family Theridiidae) from Costa Rica. Whee- scribed by Carayon (1974: figs. 25, 26). ler and McCafferty (1984; see also Henry, KEY TO SPECIES OF LIPOKOPHILA 1985: 1130) reviewed the biology of Ran- zovius clavicornis (Knight) from eastern North 1. Large species, approximate total length from America. apex oftylus to apex ofmembrane 2.70-2.90 Kerzhner (1990) described two new species mm; corium generally brown, pale basally of Arachnocoris (Nabidae) from the webs of and apically (fig. 14); pygophore elongate, tu- with the bular, and somewhat decurved (fig. 2 1), para- Pholcidae from Costa Rica, along meres nearly straight and apically decurved recognition of Arachnocoris panamensis (fig. 22); Costa Rica ...... eberhardi (Distant), from the same area. Lopez (1989) -Smaller species, approximate total length length described a new species ofArachnocoris from from apex oftylus to apex ofmembrane 2.10 the Lesser Antilles, also commensal in the mm or less; coloration and structure of py- webs ofPholcidae, bringing the total number gophore variable ...... 2 of described species to 12. Members of the 2. Hemelytra with a more or less quadrate pattern genus had previously been keyed by China of pale and brown (fig. 15); pygophore de- (1946), and a key to the Costa Rica species curved and parameres nearly straight and was provided by Kerzhner (1990). slightly decurved apically, structurally sim- The general morphology of Lipokophila ilar to eberhardi (figs. 21, 22); Costa Rica ...... tengella has been well described by Stys (1967) and -Hemelytra largely brown, with some lighter ar- amplified by Carayon (1974). The claws are eas on corium basally and apically; pygo- very long, slender, nearly straight, and of un- phore not decurved, parameres never nearly equal length (fig. 18), a feature common to straight and decurved apically ...... 3 many web-inhabiting Heteroptera (Cobben, 3. Pygophore very short, parameres broadened 1978; Stys, personal commun.). There is a mesially, narrowing and recurved apically single setiform parempodium associated with (Carayon, 1974: fig. 23); Santa Catarina, Bra- the longer claw. By contrast, the claws of an zil ...... stysi undescribed Embiophila sp. from near Tax- -Pygophore weakly elongate, parameres slender co, Mexico, are relatively shorter, stouter, and and ofnearly uniform width ofentire length, very broadly curving and nearly forming a more strongly curved and both parempodia semicircle (Carayon, 1974: fig. 24); Santa Ca- are lacking. tarina, Brazil ...... chinai In the first instar nymph of Lipokophila eberhardi the compound eye is composed of Lipokophila eberhardi Schuh, five ommatidia with a single central eye seta new species and a second seta lying outside the ring of Figures 14, 16-22 ommatidia (fig. 17), conforming in general to the pattern in the Euheteroptera described by HOLOTYPE: 6, COSTA RICA: Heredia Cobben (1978). Prov.: La Selva, nr. Puerto Viejo, ca. 100 m, The corium in L. eberhardi is uniformly Apr. 1983, W. Eberhard, on webs of Tangella covered with what Carayon (1974) referred radiata; deposited in AMNH. to as corial glands. Under transmitted light DiAGNosIs: Recognized as a member ofLi- 1 993 EBERHARD ET AL.: TENGELLA SYMBIONTS 13

i.:ir

Figs. 14-17. 14. Lipokophila eberhardi Schuh, new species, male, habitus. 15. L. tengella Schuh, new species, female, habitus. 16. L. eberhardi, fifth instar nymph, lateral view of head. 17. L. eberhardi, first instar nymph, lateral view of head. pokophila by the long, three-segmented tarsi nae, and coxae deep brown to castaneous; and the structure of the male genitalia. Dis- pronotal collar and most of exocorium pale tinguished from its congeners by its large size and distinctly contrasted with surrounding (total length 2.70-2.90 mm) and largely brown areas; legs, including trochanters, light brown. coloration of the hemelytra (fig. 14). Membrane with a large, round, whitish area DEScRIPTION: MACROPTEROUS MALE. laterally and just posterior to cuneus and a Coloration, vestiture, and surface texture. smaller, lateral, subapical whitish area. Head General coloration ofdorsum, venter, anten- and venter polished and shining; pronotum 14 AMERICAN MUSEUM NOVITATES NO. 3065 pp-.P"pp,

Figs. 18-21. Lipokophila eberhardi Schuh, new species. 18. Pretarsus, foreleg. 19. Detail o0 pretarsus, foreleg. 20. Corial surface showing corial gland openings. 21. Lateral view of phygophore. and hemelytra appearing smooth but dull. apex tylus-cuneal fracture 2.70; width head Entire body clothed with relatively short, re- across eyes 0.30; interocular space 0.18; length clining, golden, common setae. pronotum 0.52; width pronotum 0.78; length General structure. Very similar to that of antennal segment 2 0.55. Lipokophila chinai as described by Stys MACROPTEROUS FEMALE. General (1967). Antennal segments 3 and 4 subequal coloration, vestiture, and structure as in male. in length to segment 2 and somewhat more Ovipositor valves completely absent. Length slender. Dorsal external orifices of corial apex tylus-cuneal fracture 2.90; width head glands as in figure 20. Pretarsus as in figures across eyes 0.30; interocular space 0.17; length 18 and 19, claws nearly straight over most of pronotum 0.48; width pronotum 0.80; length length, of conspicuously unequal length, a antennal segment 2 0.56. single parempodem present. Genital capsule NYMPHS. Compound eye of first instar and parameres as in figures 21 and 22. Length with five ommatidia and a single centrally 1993 EBERHARD ET AL.: TENGELLA SYMBIONTS 15

located seta (fig. 17). Compound eye of fifth 22 instar similar to adult (fig. 18). ETYMOLOGY: Named after the collector, William G. Eberhard. PARATYPES: Same data as holotype, 416, 262 (AMNH; Universidad de Costa Rica). COSTA RICA: Puntarenas: Monteverde, 1500 m, Jan. 1983, W. Eberhard, on agelen- did web, SA1-92A (AMNH), 1Q; Monte- verde, 1350 m, nr cheese factory, June 1986, W. Eberhard (AMNH), 12 in agelenid web, Fig. 22. Lipokophila eberhardi Schuh, new spe- 16, 3Q in web of Tengella radiata. San Jose: cies, lateral view ofpygophore, showing parameres San Antonio de Escazu, 1400 m, June 1983, and phallus. W. Eberhard, in web of Tengella radiata (AMNH), 76, 72. ADDITIONAL SPECIMENS: COSTA RICA: Same data as holotype, approximately 80 trasted with surrounding areas; legs, includ- nymphs (some of these may belong to Li- ing trochanters, light brown. Membrane with pokophila tengella). San Jose: San Antonio a large, round, whitish area laterally and just de Escazu, 1400 m, June 1983, W. Eberhard, posterior to cuneus and a smaller, lateral, in web of Tengella radiata (AMNH), 6 subapical whitish area. Head and venter pol- nymphs. ished and shining; pronotum and hemelytra appearing smooth but dull. Entire body Lipokophila tengella Schuh, clothed with relatively short, reclining, gold- new species en, common setae. Figure 15 General structure. Very similar to that of L. eberhardi, but overall dimensions smaller. HOLOTYPE: 6, COSTA RICA: Heredia Male genitalia similar in structure to those of Prov.: La Selva nr. Puerto Viejo, ca. 100 m, L. eberhardi. Measurable male specimens not Apr. 1983, W. Eberhard, on webs of Tengella available. radiata; deposited in AMNH. MACROPTEROUS FEMALE. General DiAGNOsIs: General structure similar to that coloration, vestiture, and structure as in male. of L. eberhardi, but differing as follows: Ovipositor valves completely absent. Length smaller, total length offemale approximately apex tylus-cuneal fracture 2.07; width head 2.07, basal one-third ofcorium pale, exorium across eyes 0.23; interocular space 0.15; length dark across middle one-third, in conjunction pronotum 0.65; width pronotum 0.58; length with dark cuneus giving appearance of four antennal segment 2 0.28. large, dark maculae on hemelytra (fig. 15). ETYMOLOGY: Named for its occurrence in DESCRIPrION: MACROPTEROUS MALE. the webs of Tengella; a noun in apposition. Coloration, vestiture, and surface texture. PARATYPES: Same data as holotype, 16, 32 General coloration ofdorsum, venter, anten- (AMNH). COSTA RICA: San Jose: Braulio nae, and coxae deep brown to castaneous; Carrillo N. P., Send. Nat. cloud-rainforest pronotal collar, and one-third ofcorium, and trans., 1100 m, Apr. 29-30, 1983, D. Ubick, antennal segment 4 pale and distinctly con- ex Tengella web (AMNH), 12.

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