Jaltomata darcyana Mione
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The information on this page may be cited as a communication with professor Thomas Mione, Central Connecticut State University, Biology Department, Copernicus Hall, 1615 Stanley Street, New Britain, CT 06050-4010
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Mexico and Central America
Jaltomata darcyana is known only from the seasonally dry Pacific Coast of Costa Rica where it grows at lower elevations than the other Jaltomata species of Costa Rica. The combination of large somewhat coriaceous leaves, and flowers that lack protogyny, last only a single day and have curved styles, contributed to the recognition of this taxon as a distinct species. It is possible that this species will be found in similar habitats (low elevation, seasonally dry) elsewhere in Central America (Nicaragua?).

Upper Left: Flower. This species lacks a pistillate phase (anthers open and present pollen as soon as the flower opens). Early September 2002.

Upper Right: Ripe fruit and unripe fruit turned downward. Metric ruler across top.

Left: Two inflorescences, each with one open flower.

Lower Left: Overhead view of flower. Shape of the base of the stamen is evident, as are corolla maculae and curved style.

Lower Right: Flower. One stamen was removed to reveal style and ovary. Droplets of clear nectar are evident on the corolla where the corolla meets the expanded bases of the stamens. Anthers have all dehisced.

All Photos by T. Mione in Connecticut, USA of plants grown from seeds of the type collection Mione & Yacher 694.


Reproductive Biology of Jaltomata darcyana

This species is self-compatible and autogamous, based on abundant fruit production by spatially isolated plants grown for study in 2000, 2001 and 2002. 

Nectar: Translucent nectar droplets were observed where the corolla and androecium meet. This nectar is likely produced by the ovarian disk and then, taking the path of least resistance, seeps through the bases of the stamens on to the corolla.

Flowers of this species last only a single day during which they are functionally hermaphroditic. The flowers of all other Jaltomata of the black/purple fruited clade studied to date last at least two days and are always pistillate for a day prior to filament elongation and anther dehiscence. In contrast, J. darcyana has lost this initial period during which the flower cannot self-pollinate. To date, this is the only Jaltomata species of the black/purple fruited clade that is not protogynous. Link to Floral Phenology of Jaltomata darcyana.

Cleistogamy: Plants grown in Connecticut showed self-pollination in the bud! The above bud (left) would open for the first time the day after this photo was taken (note small slit beginning to appear where corolla lobes meet). When I opened the bud (with fine forceps) I found (flower above right) that all five anthers had dehisced. Now we can see (above right) that the style curves slightly, and pollen is present on the stigma; the curve of the style seems to facilitate self-pollination. WE CAN SEE POLLEN ON THE STIGMA in the above right photo, pollen that either got there prior to my opening the bud, or during the opening of the corolla (by me). Given the curve of the style, it is entirely possible that the pollen got on the stigma (pollination took place) prior to the bud being manually opened.

In both of these photos two mm were cut from a plastic ruler, taped to the plant, and can be seen in the photos. All Photos by T. Mione in Connecticut, USA; plants grown from seeds of the type collection Mione & Yacher 694.

Seed Germination: Seeds planted 1 April 2009 germinated sporadically; 5 showed their first above-ground sign of germination on 6 June 2009, over 2 months after being planted! Germination was very poor indoors where there was no natural light, distilled water was used for watering, and a heat mat was used to warm cups holding seeds). When the cup holding the seeds was placed outdoors (date not recorded, approximately end of May or first few days of June) germination was triggered. Why was germination triggered by the outdoors? Was it natural light, heat, fluctuating temperatures, drying between waterings, or some combination of these?

Seedling Hairs: Seedlings have gland-tipped stem hairs! (spring 2009).

TYPE: Costa Rica. Nicoya Peninsula, Curú, 90 46’ 50” N, 840 56’ 05” W, 98 m, edge of pasture, 11 Jan. 2000, T. Mione & L. Yacher 694 (holotype, NY!; isotypes: CONN!, CR!, MO!).
Described by Mione, T. & L. Yacher. 2005. Jaltomata (Solanaceae) of Costa Rica. In: A Festschrift for William G. D'Arcy, The Legacy of a Taxonomist. Edited by R. C. Keating, V. C. Hollowell and T. B. Croat. Monographs in Systematic Botany from the Missouri Botanical Garden Press, volume 104. ISBN 1-930723-45-8.

In this description trichomes are not gland-tipped unless indicated as such. Finger hairs are uniseriate, unbranched and multicellular. Branchlet hairs have multiple termini (Seithe, 1979). Gland-tipped finger hairs (on the Jaltomata of Costa Rica found only on the adaxial face of the corolla) have an expanded terminal cell that stains densely with neutral red. As well, the multicellular head of the stalked glands (common on the abaxial faces of the perianth) also stains densely with neutral red. Pollen grain diameter was measured after staining pollen 30 minutes in "cotton blue" stain; anthers were stored in 70% ethanol prior to staining. Floral phenology was observed in the field, and on healthy plants grown for study both outdoors, and indoors under lights. Pollen grains were counted using the method of Anderson and Symon (1989). The ovule count of one locule was doubled to obtain the total ovules per ovary.

Habit & Height Erect glabrous herb to 1.17 m high x 0.91m across.
Stems Stems hollow, green to purple, strongly angulate with 4 to 5 raised longitudinal ridges (see photos above), to 3.5 cm diameter at or just above base.
Older Branches different from younger?
Leaf Size alternate, often geminate, to 30 cm long, , the margin entire or nearly so and on smaller, younger leaves sparsely ciliolate with finger hairs to 0.1 mm long; petiole to 2.5 cm long.
Leaf Shape the blade elliptic, the proximal most 13—16% of the blade cuneate, the tip usually acuminate, the length to width ratio 1.5 to 1.8, the margin entire or nearly so
Leaf texture and hairs the faces glabrous and lustrous, somewhat coriaceous, younger leaves sparsely ciliolate with finger hairs to 0.1 mm long
Inflorescence axillary or arising from a stem dichotomy, umbellate, to 23-flowered
Peduncle & Pedicel Peduncle to 2.1 cm long and pedicel to 2.3 cm long; both green, glabrous, and with raised longitudinal ridges.
Calyx at Flowering green, 5.2—7.4 mm from pedicel to tip of lobe, 12--14 mm in diameter, the midrib raised, ciliolate near apex with 1 to 3 celled finger hairs 38—138 µm long, the hairs usually simple but occasionally with more than one terminus, abaxially with abundant stalked glands 60—75 µm long.
Corolla shape including lobes/lobules, and size rotate, 5-lobed
Corolla lobes/lobules Corolla (see above photos), light-green with dark-green maculae collectively stellate in outline, 17—20 mm (-25 mm, cultivated) in diameter, the margin ciliolate with branchlet hairs to 190 µm long, adaxially densely pilosulose with erect, gland-tipped (droplet-tipped on fresh flowers) finger hairs, (4) 5—6 celled and 210—290 µm long, abaxially with abundant stalked glands 70—80 µm long.
Corolla color and hairs
Stamens (see illustration below) 4.5—5 mm long; filaments straight or nearly so, nearly glabrous with unpigmented finger hairs to 0.3 mm long only on expanded base
Anther length & color anthers1.4—1.9 x 1.0—1.8 mm, yellow (see below illustration)
Pollen Grains 25—27.5 µm in diameter (n = 59 grains);
74,000—149,000 grains per androecium (n = 2 androecia)
Stigma green, capitate,with a shallow medial groove (when living), 0.33—0.51 mm wide (when pressed), the papillae to 28 µm long (living)
Disk around ovary off-white to light orange disk girdling the base of the dark green ovary
Style length style 4.2—5.1 mm long, curving and therefore orienting the stigma to the side (see photos above)
Ovules per ovary 158—168 per ovary (n = 2 ovaries)
Nectar Translucent nectar droplets were observed where the corolla and androecium meet. This nectar is likely produced by the ovarian disk and then, taking the path of least resistance, seeps through the bases of the stamens on to the corolla.
Herkogamy? No
Protogyny No
Fruit color (at maturity) and size Mature berries dark black-blue (see photo), subspherical, to 14 mm in diameter.
Calyx at fruit maturity to 26 mm in diameter, stellate, green, rotate to slightly reflexed, not hiding fruit in side view.
Infructescence
Seeds subovate, alveolate,1.8—1.98 X 1.41—1.62 X 0.45—0.54 mm thick,
to 146 per fruit.
Chromosome number 2n = 24. Chromosomes were counted with the method of Bernardello & Anderson (1990); to obtain root tips seeds were sown on wet filter paper in a petri dish at room temperature under ambient light.
Growability in Connecticut, USA, outdoors Easy to grow

Herba, caulibus insigniter angulatis, foliis ad 30cm longis, inflorescentiis floribus 23 ut maxime, calyce aequabiliter viridi, corolla rotata, filamenta recta, antheris non mucronulatis, stylo curvo dirigente stigma ad latus, floribus numquam non hermaphroditis.

Paratypes. COSTA RICA. Guanacaste: Santa Rosa National Park, ca. 10 50’ N., 85 37’ W., 0--320 m, 16 July 1981, Janzen 12113 (MO), and 10 50’ N., 85 35’ W., 8 Nov. 1981, Janzen 12125 (F); Nicoya Peninsula, Cantón Nandayure, Pilas de Bejuco, Quebrada Seca, 9o 52’ 01” N., 85o 20’ 45” W., 40 m, 15 Oct. 1994, Estrada & Rodríguez 242 (CR, INB). Puntarenas: Reserva Biológica Carara Estación Quebrada Bonita, 9 46’ N., 84 36’ W., 30 m, 26 June 1990, Bello & Rojas 2295 (CR, F, INB); Nicoya Peninsula, Curú, pastures S of entrance road, mouth of Marianas Canyon, 50 m, 13 Sep. 1995, Sanders & Baker 17892 (F, NY).
Leaves of Jaltomata darcyana (larger) and J. spooneri (smaller and darker). These leaves were selected because they were among the largest on the plants. Plants cultivated indoors (April and May) and outdoors (June and July) by and scanning done (July 2009) by Thomas Mione. Both of the plants shown were grown from seeds of the type collections. Upper photo shows upper side of leaves; lower photo shows lower side of leaves.

 

Literature Cited