Lepanthes astraea is a small, caespitose, epiphytic orchid with fine roots. The ramicauls are slender and erect, 1.9–12.5 cm tall, with minutely verrucose ridges, enclosed by 7–10 narrowly-applied lepanthiform sheaths with oblique, narrowly-acuminate margins. The single leaf is erect, densely coriaceous, ovate and acuminate, 2.1–3.8 cm long and 0.8–1.5 cm wide, with a tridentate apex and a cuneate base contracted into a short petiole; the abaxial surface is reticulated with purple along the veins — a character visible in well-lit field photographs and a useful field-recognition feature.

The inflorescence is highly congested, distichous, with up to 6 successive racemes of many flowers each, up to 11 mm long, produced on either side of the leaf on a filiform peduncle 3–5 mm long. The floral bracts are echinate, 0.9 mm long; pedicels 1.4 mm; ovary smooth, 0.9 mm. The sepals are translucent yellow and glabrous: the dorsal sepal reflexed, elliptic, acute, 1.5 × 0.8 mm, 3-veined, connate to the laterals for 0.16 mm; the lateral sepals reflexed, elliptic, divergent, obtuse, 1.3 × 0.7 mm, 2-veined, connate for 0.3 mm. The petals are pale orange basally tinged with red, microscopically densely pubescent, transversely bilobed, 0.2 mm long at the middle — and each of the two halves is itself bifurcated, producing four narrowly linear-triangular lobules of equal length, each 0.6–0.75 mm long. This four-lobuled petal architecture is the most distinctive external character of the species. The lip is dark orange tinged with red basally and along the margins, microscopically pubescent, without blades, subcordate, 0.7 × 0.6 mm, incised at the apex by 0.32 mm into two triangular lobes with long-ciliate apex; basal lobes 0.15 mm long, connate to the base of the column. The column is red, microscopically cellular-pubescent, terete, 0.8 mm long, with apical anther and sub-apical stigma; the capsule is unknown.

Despite the flower's overall size of only 2–3 mm, the structure is intricate: paired pink-red dorsal sepals form an arched hood above the flower, the orange petals fan out laterally with their four-lobule architecture, and the rounded pink lip projects forward — an arrangement sometimes likened to a starlike or multi-armed silhouette, which the specific epithet ("astraea", from Greek astēr, "star") evokes.

The morphological characters described here follow the protologue: Vieira-Uribe & Larsen (2014), Orquideología 31: 12.

According to the protologue, Lepanthes astraea grows as an epiphyte at 1,900–2,000 m elevation in well-conserved, very humid montane forest, both in the forest interior and along forest edges, usually within two metres of the ground, often co-occurring with Lepanthes escifera. Vieira-Uribe & Larsen (2014) also reported the species growing on moss-covered concrete bridge railings beside a forest river, alongside Lepanthes acarina, Fissia picturata (Rchb.f.) Luer, Buccella molossus (Rchb.f.) Luer, and other Pleurothallidinae — an unusual substrate observation that suggests the species accepts mineral surfaces with sufficient bryophyte and moisture cover.

In La Honda, L. astraea has been observed both as an epiphyte and growing on wet, moss-covered stones beside trails, the latter directly consistent with the protologue's bridge-railing observation. Plants flower successively in La Honda almost throughout the year, again matching the protologue's note that cultivated plants flower year-round and that the same pattern is presumed in situ.

Lepanthes astraea is endemic to the eastern slope of the Cordillera Central in Antioquia, Colombia. The species was described from two localities: the holotype from Guatapé, vereda El Rosario, at 1,950 m (S. Vieira 0017, JAUM); and the paratype from El Carmen de Viboral, vereda Santo Domingo, at 2,000 m (S. Vieira 0018, JAUM). Vieira-Uribe & Larsen (2014) describe the species as known only from this corner of eastern Antioquia, on the eastern flank of the Cordillera Central east of Medellín.

The La Honda record extends the documented occurrence by approximately 5 km northwest of the paratype locality, within the same biogeographic corridor of eastern-Antioquian montane forest. La Honda is, to date, the closest documented occurrence of L. astraea to its paratype locality.

Lepanthes astraea has been observed flowering successively almost throughout the year in La Honda — consistent with the protologue's observation that cultivated plants flower year-round, and that the same pattern is presumed to occur in situ. The successive-flowering pattern (multiple racemes producing flowers in sequence rather than synchronously) is a useful field-survey character: a fertile plant of L. astraea is rarely without at least one open flower or developing bud at any time of year.

Recognition rests on a combination of vegetative and floral characters. Vegetatively, the densely coriaceous ovate leaf with a tridentate apex and purple-reticulated abaxial veins is a useful starting feature, alongside the slender, minutely-verrucose ramicauls 1.9–12.5 cm tall enclosed by 7–10 narrowly-applied lepanthiform sheaths.

Florally, the diagnostic character is the four-lobuled petal architecture: each transversely bilobed petal is itself bifurcated into two narrowly linear-triangular lobules of equal length, producing four projecting "arms" total per petal. This is the source of the species's epithet (astraea, "starry"). Combined with the translucent yellow reflexed sepals, the bright pink-red lip, and the small overall flower size (~2–3 mm across), the four-lobuled orange petals make the species unambiguous in the field. The successive-flowering habit and frequent occurrence on moss-covered mineral substrates (stones, bridge railings) provide additional secondary clues.

Lepanthes astraea has not been evaluated globally on the IUCN Red List (status NE, Not Evaluated, as of the date of this sheet). At the national regulatory level in Colombia, the species is not listed in Resolución 0126 de 2024 of the Ministry of Environment; it is therefore not classified as threatened under current Colombian environmental law.

"Not Evaluated" is not a statement that the species is safe — it is a statement that no formal assessment has been made. The species is currently known only from a small portion of eastern Antioquia, and the type and paratype localities both lie in a landscape under continuing pressure from agricultural expansion, road infrastructure, and the residential and recreational development associated with the reservoir corridor at Guatapé. The narrow documented range, combined with the species's epiphytic and lithophytic habitat preferences, suggests that population persistence depends on the continuity of mature-secondary cloud forest and undisturbed mossy substrates at the documented elevations.

For these reasons — and to maintain consistency with the locality-redaction practice applied to the other Lepanthes sheets in this book — the specific location within La Honda where L. astraea has been documented is not published. Requests for further locality detail from researchers or conservation practitioners with a legitimate scientific or institutional purpose may be directed to [email protected].