Carl Weekley
Archbold Biological Station
P.O. Box 2057
Lake Placid, FL 33862

Abstract

Tanaostigmodes pithecellobiae LaSalle, a chalcidoid wasp, induces foliar galls on Pithecellobium keyense Britton ex Britton & Rose, a mimosoid legume native to South Florida. This paper provides the first description of the gall-maker’s natural history: it is monophagous and multivoltine; its phenology varies with the season of gall initiation; and it is preyed upon by chalcidoid parasitoids and by an unusual microlepidopteran "gall-miner".

Key Words: insect gall-makers, cecidology, plant galls, gall-making wasps

Resumen

Tanaostigmoides pithecellobiae LaSalle es una avispa que induce la formación de agallas en hojas de Pithecellobium keyense Britton ex Britton y Rose, una planta leguminosa originaria del sur de la Florida. Este trabajo representa la primera descripción de la historia natural de este insecto. Esta especie es monófaga, multiovular y su fenología varía con las épocas de producción de agallas. Es parasitada y devorada por chalcicoides y por un microlepidóptero poco común que causa minas en las agallas.

Tanaostigmodes pithecellobiae LaSalle (Hymenoptera: Tanaostigmatidae) induces foliar galls on Pithecellobium keyense Britton ex Britton & Rose, blackbead, a mimosoid legume native to South Florida. The gall-maker was named and described in LaSalle’s (l987) taxonomic revision of the New World Tanaostigmatidae, a small but well-circumscribed family of gall-making chalcidoids. It is indicative of the present state of knowledge of the Tanaostigmatidae that of the 74 New World species treated in LaSalle’s monograph, two-thirds (49) were new to science. The present paper is among the first to characterize the biology of a tanaostigmatid.

Blackbead is an arborescent, evergreen shrub of the coastal scrub zone and of pineland and hammock margins (Tomlinson 1980). Its leaves are bipinnately compound, with four to eight leaflets in two pairs (Tomlinson 1980). The leaflets are elliptical to obovate, 4-5 cm long, and dark green and leathery at maturity. New growth is produced in recurrent flushes throughout the year, but appears least abundant during the dry season. During the initial stage of leaf development, which lasts about 1 week, opposite leaflets are oriented with their upper surfaces facing one another, leaving the lower surfaces exposed (personal observation).

The congeneric P. unguis-cati (L.) Benth., catsclaw, is also listed by LaSalle as a host species for T. pithecellobiae. Catsclaw closely resembles blackbead in leaf and flower morphology and occupies similar coastal habitats (Wunderlin 1998, Tomlinson 1980). Blackbead and catsclaw occur sympatrically in the Florida Keys, but their ranges diverge on the mainland. Blackbead occurs on the Atlantic Coast to Martin County, while catsclaw occurs on the Gulf Coast to Hillsborough County (Wunderlin et al. 1996, Isely 1990, Little 1978).

This paper establishes the host specificity of T. pithecellobiae, provides the first description of its natural history, and examines seasonal variation in gall density and patterns of development.

Materials and Methods

Host Specificity

Host-plant specificity was determined by a survey of 463 individuals of the two candidate species at nineteen sites in South Florida, extending from Key West to Sanibel Island on the Gulf coast and to Juno on the Atlantic coast. I examined blackbead and catsclaw plants in areas where they occurred together and in areas where one or the other was absent. Each plant surveyed was scrutinized for the presence of galls, and where galls were present I quantified gall density per plant by haphazardly censusing 100 leaflets. Per site gall density was estimated by calculating the mean percentage of galled leaflets based on all galled plants censused at a given site.

Natural History

Study site. The primary study site was the Deering Estate, part of the Metro-Dade Park system, in Miami, Fl. I monitored about 20 blackbead plants growing along the shoulders of a roadway through a coastal pine rockland/oak hammock established on Miami oolitic limestone. Average temperatures in Miami range between 10 and 32°C (Tomlinson 1980), with an annual average of ~23°C (Migliaccio 1987). Rainfall averages ~1500 mm per year, with about 70% of the annual precipitation occurring during the May-to-October rainy season (Migliaccio 1987).

Gall-maker phenology. To determine gall-maker phenology, I followed the development from oviposition to gall-maker emergence of successive cohorts of galled leaflets. Between July l99l and March l993, I marked seven cohorts (designated I-VII) of newly galled leaflets. Each cohort consisted of at least 100 galled leaflets. I monitored four of these cohorts (I, II, V and VII) weekly from first emergence of the gall-maker to depletion of the cohort (with an 8 week gap in the case of cohort V). I have only partial data for cohorts III and IV, and cohort VI was destroyed by Hurricane Andrew (24 August 1992) prior to maturation.

Gall demographics. From November 1991 to March 1993, I periodically collected samples of 30 leaflets with mature galls for rearing in the lab. I set up 23 such samples, comprising 690 leaflets and approximately 5,000 galls. Each leaflet was maintained in its own 16 oz plastic container with a clear plastic lid for a minimum of 2 weeks. Moist tissue paper was kept in each container to maintain humidity. Temperature in the lab was approximately 20°C.

For each leaflet, I recorded the initial number of exited and unexited galls and marked the exited galls. I censused emerging wasps by species and sex and preserved voucher specimens of all wasps obtained. At the end of the rearing period, unexited galls were dissected and gall contents were recorded. M. E. Schauff of the U.S. Department of Agriculture (USDA) Agricultural Research Service/Systematic Entomology Laboratory provided species determinations.

I periodically collected additional leaflets with mature or immature galls for observation and dissection. Galled leaflets with leaf mines that encircled or invaded developing galls were also collected. I reared the caterpillars obtained from these "gall-mines" and sent larvae, pupae and moths to R. W. Hodges of the USDA Agricultural Research Service/Systematic Entomology Laboratory for identification.

Data Analysis

I constructed a phenology chart to show the duration of successive cohorts of galls and the timing of gall-maker emergence at the Deering Estate over a period of 22 months. To highlight seasonal variations in patterns of emergence, percent exited galls was plotted against the age of the galls (in weeks) for early, mid- and late season cohorts. To see if the proportion of emerging wasps per month differed statistically for early, mid- and late season cohorts, I used c2 contingency tables. Analysis of variance (ANOVA) was used to evaluate differences in gall density per cohort among early, mid- and late season cohorts.

To determine the statistical significance of the sex ratios for the wasps reared in the lab, I performed c2 goodness-of-fit tests.

All statistical tests were conducted using SAS version 6.1 (SAS Institute, 1990).

Results and Discussion

Tanaostigmodes pithecellobiae is monophagous (host- specific) and multivoltine. The phenology of gall-maker development varies seasonally and within a cohort. T. pithecellobiae is parasitized by at least two other chalcidoids and is preyed upon by an unusual "gall-mining" microlepidopteran.

Host Specificity

Eighty-two percent of the 266 blackbead plants censused between Key West and Juno had galls (Table 1). The percentage is even higher (96%) if the 30 blackbeads surveyed north of Boca Raton, on which no galls were found, are excluded. I found no galls on the 197 catsclaws censused between Big Pine Key and Sanibel Island.

In populations of blackbead containing galls, the mean percentage of galled leaflets per site (based on haphazard censuses of 100 leaflets per galled plant) varied from <10 to >40% (Table 1).

In addition to blackbead (P. keyense), LaSalle (1987) lists the sympatric catsclaw (P. unguis-cati) as a host plant for T. pithecellobiae. But LaSalle examined only museum specimens of T. pithecellobiae galls, and the congeneric putative host plants are often confused. From my survey of blackbead and catsclaw plants growing throughout most of their South Florida ranges, I conclude that only blackbead is a host for T. pithecellobiae, and that the gall-maker is therefore monophagous in the strictest sense (i.e., a single host-plant species).

At present, T. pithecellobiae is recorded only from Florida (LaSalle 1987). The distribution of its host plant is, however, complicated by taxonomic uncertainties. Long & Lakela (1976) list P. keyense as a South Florida endemic. Wunderlin et al. (1996) and Wunderlin (1998), using the same binomial, do not consider the taxon a Florida endemic, but fail to specify its range beyond Florida. Other authors (e.g., Little 1978, Tomlinson 1980, Isely 1990) refer to blackbead as P. guadalupense (Pers.) Chapm., with a distribution which includes the Yucatan peninsula and the West Indies. Further clarification of the degree of host specificity of T. pithecellobiae requires resolution of the taxonomic status and geographical distribution of its Florida host plant.

The absence of T. pithecellobiae galls from the 30 blackbead plants surveyed north of Boca Raton suggests that the gall-maker may be excluded from the northernmost parts of its host plant’s range.

Gall-maker Phenology

Tanaostigmodes pithecellobiae females oviposit on the lower surface of expanding leaflets within 1 week of bud break. One bladder of the encyrtiform egg is inserted beneath the lower epidermis of the rapidly growing young leaflet; the other bladder, connected to the first by a short stalk, remains on the leaflet surface for 1 or 2 days. Apparently the inserted bladder absorbs the contents of the external one, which disappears. Within a few days the eggs hatch and larval feeding begins.

Gall development parallels leaflet development. It takes 8 to 10 weeks for leaflets to become dark green and leathery. During this time the galls develop from pimple-like eruptions on the upper surface of the leaflet to tumor-like swellings. Galls mature in about 10 weeks and do not change in physical appearance until emergence of the adult gall-maker (or one of its parasitoids). Gall-maker emergence begins only after 14 weeks (later for overwintering galls). Exited galls necrose and once all the galls are exited the leaflet abscises prematurely.

Since blackbead produces flushes of new growth throughout the rainy season, T. pithecellobiae is able to initiate several (overlapping) generations per year. A mass emergence of overwintering gall-makers may result in high densities of galls (per leaflet) on the first rainy season flush. Because of differential rates of gall-maker development within a cohort, emergences may be staggered to take advantage of the patchier availability of oviposition sites as the season progresses.

The time required for the development of insect gall-makers from oviposition to eclosion of the adult varies from a few days to over a year (Mani 1964) and may be prolonged by diapause (Mani 1964, Abrahamson and Weis 1987). T. pithecellobiae galls initiated in early or mid-season (March-July) may complete their emergence in as few as 14 weeks. Some mid-season wasps, as well as wasps oviposited late in the season, apparently undergo larval diapause and thus avoid emergence in the dry season when oviposition sites are unavailable.

Gall Demographics

Between February 1992 and March 1993, I reared 892 wasps from galls collected at the Deering Estate. Excluding 4 unidentified wasps of uncertain role, 65% were T. pithecellobiae and 35% were parasitoids belonging to 2 chalcidoid genera in the Eulophidae (Table 2). Chrysonotomyia sp. outnumbered Aprostocetus sp. by 2 to 1. Neither has been identified to species (M. E. Schauff personal communication). I obtained pupae of both parasitoid species from dissected galls and it appears that both are endoparasitoids on the later stages of gall-maker development.

Sex ratios of the gall-maker and its 2 major parasitoids showed a statistically significant 60:40 female bias (Table 2).

The only predator obtained was an undescribed microlepidopteran in the Cosmopterygidae (R. W. Hodges personal communication). The caterpillar mines into developing galls and consumes both gall tissue and the gall-maker, leaving only the upper and lower epidermis of the leaflet.

The "gall-mining" caterpillar is of interest both taxonomically—it may represent a new genus within the family Cosmopterygidae (Hodges personnel communication)—and ecologically. Mani (1964) recognized "cecidophages" (i.e., "gall-eaters") as a "highly specialized group that feed either preferentially or obligatorily on galls". He singled out "cecidophagous insects [which] bore into the tissues of galls, eating the entire flesh [of the gall] and leaving only the outer skin in the form of an empty bag, inside of which they even pupate". Several microlepidoptera are mentioned by Mani as belonging to this category.

Table 2. A summary of wasps reared over a 13 month period (February 1992 to March 1993) from galled leaflets collected at the Deering Estate, Miami. Sex ratios are significantly female-biased; sex ratios among the three species did not differ. Total percent parasitism = 35.4%.
Species
Sex ratios
% of galls yielding each species
Number females
Number males
Total number
% female
T. pithecellobiae
345
231
576
59.91
64.6
Chrysonotomyia sp.
126
90
216
58.32
24.2
Aprostocetus sp.
61
39
100
61.03
11.2
Totals
532
360
892
59.64
100.0
1c2 (1) = 22.16, p < 0.01.
2c2 (1) = 5.67, p < 0.025.
3c2 (1) = 19.36, p < 0.01.
4. c2 (2) = 0.246, p > 0.88.
Gall Season and Cohort Longevity

There was a distinct seasonality to gall-maker development as shown by the 7 cohorts monitored at Deering Estate over a 22 month period (Fig. 1). Gall season, the period of gall initiation and active development, corresponds roughly to the traditional South Florida rainy season (Chen and Gerber 1990), anticipating it by 2 months (March-April) during which mean precipitation increases from the November-February low. Within the gall season, I distinguish 3 periods: early (March-April), mid (May-July) and late (August-September). Each of the 7 cohorts was initiated during one of these three periods. Cohort VI was destroyed by Hurricane Andrew prior to maturation and is excluded from the following analysis.

The 2 early season cohorts, cohorts III (early March 1992) and IV (mid April 1992), showed first emergences in their 14th and 16th weeks, respectively (though for cohort IV, I do not have a confirmed gall-maker exit for that period) (Fig. 1). Data are not available for these 2 cohorts from mid June to late August. But on August 21, with only 18% of its original 1,195 galls present (80% of which were exited), cohort III had essentially completed its development within 24 weeks. Similarly, only 14% of cohort IV’s original 1,141 galls remained on August 21, its 16th week, and of these 16% showed exit holes. It is likely that many (if not most) of these galls were exited before August 21 and their leaflets abscised. Further development of these cohorts was cut short by Hurricane Andrew.

The 2 mid season cohorts, cohorts I (mid-July 1991) and V (mid-June 1992), also produced gall-maker adults after 14 weeks, but emergence was discontinuous, with a hiatus during the dry season (Fig. 1). For cohort I there was a 12 week gap (November-February), after which emergences resumed and continued until April. Data are lacking for cohort V from November to early January, but I have records for weekly emergences from January to March (Fig. 2). Thus cohort V deviated from the pattern set by cohort I by yielding gall-makers during the dry season. For both cohorts gall-maker emergence extended over a period from 14 to 32+ weeks.

The two late season cohorts, cohorts II (mid- September 1991) and VII (early September 1992), were both initiated within 8 weeks of the onset of the dry season (Fig. 1). Cohort II yielded wasps only after 21 weeks, while cohort VII began to show exits at week 20 (Fig. 2). Both cohorts produced continuous weekly emergences at least through their 30th weeks. In both cases gall-maker emergence was delayed by the onset of the dry season. However, cohort VII wasps began to emerge in January 1993, about 2 months earlier than cohort II wasps had emerged the previous year.

The earlier emergences of cohort V and cohort VII gall-makers compared to the corresponding cohorts of the previous year correlate with higher temperatures (Fig. 3) and greater rainfall (Fig. 4) in January 1993 compared to January 1992.

Seasonal Variation in Patterns of Development and Gall Density

Comparison of early, mid-, and late season cohorts revealed distinctly different seasonal patterns of emergence (Fig. 2). Cohort III gall-makers developed more rapidly than cohort V or cohort VII gall-makers, as measured by the proportion of exited galls per month for the three cohorts (c2(2) = 528.2, p < 0.001). Gall densities, the mean number of galls per leaflet, also varied with the season, being significantly greater for early season than for either mid- or late season galls (Table 3).

Gall densities and patterns of gall-maker emergence varied among early, mid- and late season cohorts. Early season cohorts had statistically greater gall densities (per leaflet) and completed development more rapidly than either mid- or late season cohorts (Table 3, Fig. 2). Greater gall densities per leaflet early in the season were related to the mass emergence of overwintering wasps.

Table 3: A comparison of the mean number of galls per leaflet for early (III), mid- (V), and late (VII) season cohorts of galls at the deering estate. the mean number of galls per leaflet was significantly greater for early season cohort III than for mid-season cohort V or late season cohort VII.

Cohort
Number galled leaflets
Mean number galls/leaflet1
III
106
11.23 ± 16.4
V
91
5.5 ± 4.5
VII
93
4.2 ± 2.8
1F(2, 287) = 13.34, p < 0.001.

Emergence schedules were protracted in mid- and late season cohorts compared to early season cohorts. Most early season wasps emerged within 24 weeks, with the first emergences at 14 weeks (Fig. 2). Some mid-season wasps also emerged in 14 weeks, but some overwintered and resumed emergence over a period from 26 to 32 weeks. No wasps emerged in 14 weeks in either of the two late season cohorts. Emergences began only after 20 weeks for cohort II and 21 weeks for cohort VII, and for both cohorts emergences continued for more than 30 weeks.

Insect gall-makers co-opt host plant resources and are thus dependent on the availability of those resources (Hovanitz 1959, Abrahamson & Weis 1987, Hori 1992). Seasonal variation in patterns of gall-maker development on blackbead are undoubtedly related to plant resource allocation which varies from wet to dry season. Within-cohort variations may be due to environmental stimuli, condition of the host plant, gall density per leaflet, per leaf, or per plant, or some combination of these factors.

Comparison of T. pithecellobiae’s phenology to that of other gall-making tanaostigmatids is precluded for lack of information on other species. A non-gall-making tanaostigmatid from India, T. cajaninae LaSalle, ecloses in less than three weeks (Lateef et al. 1985).

Acknowledgments

This research was conducted in partial fulfillment of the requirements for a Master of Science in Biology at Florida International University (FIU) and was supported by an FIU Teaching Assistantship and by a Grant-in-Aid of Research from Sigma Xi, The Scientific Research Society. For their support and advice, I thank the members of my graduate committee: Suzanne Koptur (chairperson) and Steve Oberbauer of FIU and Jorge Peña of the Tropical Research and Education Center (Institute of Food and Agricultural Sciences/University of Florida). For species determinations, I thank M. E. Schauff and R. W. Hodges of the USDA Agricultural Research Service/Systematic Entomology Laboratory. For permission to work at the Deering Estate, I thank Metro-Dade Natural Areas Management. I also thank Gary Steck, John LaSalle, and an anonymous reviewer for their editorial comments and advice.

References Cited

Abrahamson, W. G., and A. E. Weis. 1987. Nutritional ecology of arthropod gall makers, pp. 235-258 in F. Slansky and J. G. Rodriquez [eds]. Nutritional ecology of insects, mites, spiders and related invertebrates. John Wiley & Sons, Inc., New York, NY. 1016 pp.

Chen, E., and J. F. Gerber. 1990. Climate, pp. 11-34 in R. L. Meyers and J. J. Ewel [eds]. Ecosystems of Florida. Univ. Central Florida Press, Orlando, FL. 765 pp.

Hori, K. 1992. Insect secretions and their effect on plant growth, with special reference to Hemipterans, pp. 157-170 in J. D. Shorthouse and O. Rohfritsch [eds]. Biology of insect-induced galls. Oxford University Press, New York, NY. 285 pp.

Hovanitz, W. 1959. Insects and plant galls. Scientific American. 201: 1511-162.

Isely, D. 1990. Vascular flora of the southeastern United States. Vol. 3, Part 2 Leguminosae (Fabaceae). Univ. North Carolina Press, Chapel Hill, NC. 277 pp.

Lasalle, J. 1987. New World Tanaostigmatidae (Hymenoptera, Chalcidoidea). Contributions of the American Entomological Institute. 23: 1-181.

Lateef, S. S., W. Reed, and J. Lasalle. 1985. Tanaostigmodes cajaninae LaSalle sp. n. (Hymenoptera: Tanaostigmatidae), a potential pest of pigeon pea in India. Bull. ent. Res. 75: 305-313.

Little, E. L., Jr. 1978. Atlas of United States trees. Vol 5: Florida. U.S. Government Printing Office, Washington, DC.

Long, R. W., and O. Lakela. 1976. A flora of tropical Florida. Univ. Miami Press, Miami, FL. 963 pp.

Mani, M. S. 1964. Ecology of plant galls. Dr. W. Junk Publishers, The Hague, The Netherlands.

Migliaccio, C. P. 1987. Dade County’s natural environment, pp. 4-25 in S. Ross, D. M. Ross and J. E. Podgor, Jr. [eds]. The Dade County environmental story. Environment Information Service of Friends of the Everglades, Miami Springs, FL. 255 pp.

Statistical Analysis System (SAS). 1990. SAS/STAT user’s guide. Version 6. SAS Institute Inc., Cary, NC.

Tomlinson, P. B. 1980. The biology of trees native to tropical Florida. Harvard University Printing Office, Allston, MA. 480 pp.

Wunderlin, R. P., B. F. Hansan, and E. L. Bridges. 1996. Atlas of Florida vascular plants. Institute for Systematic Botany, University of South Florida, Tampa, FL.

Wunderlin, R. P. 1998. Guide to the vascular plants of Florida. University Press of Florida, Gainesville, FL. 806 pp

Table 1. A survey of 463 individuals of blackbead and catsclaw at nineteen sites from Key West to Sanibel Island on the Gulf Coast and to Juno on the Atlantic Coast. Shown are the total number of plants censused at each site; the number of each species censused; the percent of individuals of each species with galls; and, for blackbead, the mean percent of galled leaflets per site (based on censuses of 100 leaflets per galled plant at each site).

Date
Site
Location
Total
number plants surveyed
Blackbead
Mean %
galled
leaflets
per site
Catsclaw
Number
plants
% Plants
with galled
leaflets
Number
plants
% Plants
with galled
leaflets
12/31/91
Harry Harris Rd.
Key Largo
100
60
92
24.3 ± 18.8
40
0
12/31/91
Easement PP181
Key Largo
49
42
100
18.1 ± 9.7
7
0
12/31/91
Dynamite Docks
Key Largo
50
12
100
9.3 ± 5.7
38
0
12/31/91
Old SR 905
Key Largo
2
2
100
NA
0
0
06/10/92
Deering Estate
Miami
20
20
100
NA
0
0
06/26/93
Cactus Hammock
Big Pine Key
30
5
100
36.2 ± 13.97
25
0
06/26/93
Wilder Blvd.
No Name Key
10
10
100
25.9 ± 9.2
0
0
06/26/93
Blue Hole
Big Pine Key
10
10
100
42.3 ± 19.2
0
0
06/26/93
Roadway
Little Torch Key
10
10
90
13.4 ± 7.3
0
0
06/26/93
Roadway
Sugarloaf Key
10
10
100
19.4 ± 9.1
0
0
06/26/93
Little Hamaca Park
Key West
10
10
100
37.0 ± 13.9
0
0
07/17/93
Catsclaw Trail
Rookery Bay
36
0
0
NA
36
0
07/17/93
Delnor-Wiggins Pass
Naples
21
0
0
NA
21
0
07/17/93
Ding Darling NWR
Sanibel
30
0
0
NA
30
0
07/31/93
H. T. Birch State Park
Ft. Lauderdale
25
25
100
43.1 ± 13.0
0
0
07/31/93
Red Reef Park
Boca Raton
9
9
78
17.8 ± 19.9
0
0
07/31/93
Gumbo Limbo EnvCnt
Boca Raton
2
2
0
NA
0
0
07/31/93
MacArthur Beach SP
N. Palm Beach
19
19
0
NA
0
0
07/31/93
A1A N of Marcinski
Juno
20
20
0
NA
0
0
Totals
463
266
82
197
0

Fig. 1. A 22-month history of seven successive cohorts of galls at the Deering Estate, Miami (July 1991 to June 1993). Gall season (March to October) is indicated by stippled background. Width of horizontal bars indicates duration of cohort. Stars show first confirmed emergence of T. pithecellobiae; dots show weeks for which additional exits—either T. pithecellobiae or parasitoids—were recorded. Heavy vertical line represents Hurricane Andrew (August 24, 1992).

Fig. 2. Seasonal variation in patterns of gall-maker emergence. A comparison of the seasonal variation in patterns of gall-maker emergence among early (III), mid- (V) and late (VII) season cohorts of galls at the Deering Estate, Miami. Percent exited galls based on total number of exited galls recorded. Dotted lines for cohorts III and V indicate weeks for which data are unavailable. Cohort III galls were initiated about 1 March 1992; cohort V galls initiated about 10 July 1992; cohort VII galls initiated about 1 September 1992.

Fig. 3. A comparison of average monthly temperatures in °C for South Dade County for the winter of 1991-92 versus 1992-93. The sharp increase in monthly average temperature for January 1993 compared to January 1992 corresponded to the early emergence of overwintering gall-makers in cohorts V and VII. Temperature averages computed from data collected in Homestead and supplied by the U.S. Weather Service.

Fig. 4. A comparison of total monthly rainfall in mm for South Dade County for the winter of 1991-92 versus 1992-93. The sharp increase in rainfall for January 1993 compared to January 1992 corresponded to the early emergence of overwintering gall-makers in cohorts V and VII. Rainfall totals computed from data collected in Homestead and supplied by the U.S. Weather Service.