Ptychococcus
Encyclopedia
Ptychococcus is a monoecious genus
of flowering plant
in the palm
family from New Guinea
and the Solomon Islands
. They are closely related to Ptychosperma
, only differentiated by the seed shape and endocarp type. The name is a combination of the Greek
for "fold" and the Latin
for "berry".
ed. The leaf
is pinnately compounded, in long sheaths, usually covered in scales and hairs, as is the short petiole
. The ridged rachis
is flattened on the bottom and also covered in hairy tomentum
. The unusual leaflets are once-folded and toothed, twisting upwards in their bottom half. Each leaflet also bears scales and a prominent midrib, with tomentose margins, and lacking visible veinlets.
The inflorescence
emerges below the crownshaft
, stiff and horizontal, and branched to three orders. Covered in scales, the peduncle
is short and thick, the prophyll is tubular, beaked and tomentose, and the long rachis bears numerous short rachillae which are often Z-shaped. The rachillae bear short round bracts subtending triads of large flower
s throughout.
The staminate flowers are more or less asymmetrical and bear three distinct, hairy sepal
s, and three ovate, scaly petal
s. There may be as many as 100 stamens, with short filaments, and elongated, apically-notched, deeply-bifid
anthers. The exine is finely reticulate and tectate. The pistilode is bottle-shaped and has pointed tips. The pistillate flowers are smaller, ovoid, and occasionally hairy; both sepals and petals are imbricate, the latter bearing scales. There are three united staminodes forming a small cup, the gynoecium
is ovoid and uniovulate; the pendulous stigma has three lobes. The fruit
is egg-shaped with a wrinkly exterior, divided into lobed segments when dry, and mature at orange or red. The epicarp is fibrous, the mesocarp fleshy, covering a five-lobed seed
, resembling the dry fruit.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of flowering plant
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
in the palm
Arecaceae
Arecaceae or Palmae , are a family of flowering plants, the only family in the monocot order Arecales. There are roughly 202 currently known genera with around 2600 species, most of which are restricted to tropical, subtropical, and warm temperate climates...
family from New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
and the Solomon Islands
Solomon Islands
Solomon Islands is a sovereign state in Oceania, east of Papua New Guinea, consisting of nearly one thousand islands. It covers a land mass of . The capital, Honiara, is located on the island of Guadalcanal...
. They are closely related to Ptychosperma
Ptychosperma
Ptychosperma is a genus of flowering plant in the Arecaceae family. Most are native to Australia and/or New Guinea, but some have been cultivated abroad as house or garden plants.It contains the following species:*Ptychosperma burretianum...
, only differentiated by the seed shape and endocarp type. The name is a combination of the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
for "fold" and the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
for "berry".
Description
The trunks grow to 15 m, usually no wider than 25 cm, and both are solitary, ringed, and crownshaftCrownshaft
An elongated circumferential leaf base formation present on some species of palm is called a crownshaft.The leaf bases of some pinnate leaved palms form a sheath at the top of the trunk surrounding the bud where all the subsequent leaves are formed.The crownshaft...
ed. The leaf
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
is pinnately compounded, in long sheaths, usually covered in scales and hairs, as is the short petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
. The ridged rachis
Rachis
Rachis is a biological term for a main axis or "shaft".-In zoology:In vertebrates a rachis can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the rachis usually form the supporting axis of the body and is then called the spine or vertebral column...
is flattened on the bottom and also covered in hairy tomentum
Tomentum
Tomentum may refer to the following:*In botany, a covering of closely matted or fine hairs on plant leaves. *A network of minute blood vessels in the brain.* Tomentum in zoology are a short, soft pubescence...
. The unusual leaflets are once-folded and toothed, twisting upwards in their bottom half. Each leaflet also bears scales and a prominent midrib, with tomentose margins, and lacking visible veinlets.
The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
emerges below the crownshaft
Crownshaft
An elongated circumferential leaf base formation present on some species of palm is called a crownshaft.The leaf bases of some pinnate leaved palms form a sheath at the top of the trunk surrounding the bud where all the subsequent leaves are formed.The crownshaft...
, stiff and horizontal, and branched to three orders. Covered in scales, the peduncle
Peduncle (botany)
In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...
is short and thick, the prophyll is tubular, beaked and tomentose, and the long rachis bears numerous short rachillae which are often Z-shaped. The rachillae bear short round bracts subtending triads of large flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s throughout.
The staminate flowers are more or less asymmetrical and bear three distinct, hairy sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s, and three ovate, scaly petal
Petal
Petals are modified leaves that surround the reproductive parts of flowers. They often are brightly colored or unusually shaped to attract pollinators. Together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals lying...
s. There may be as many as 100 stamens, with short filaments, and elongated, apically-notched, deeply-bifid
Bifid
Bifid refers to something that is split or cleft into two parts. It may refer to:* bifid rib, a congenital abnormality of the human anatomy* bifid penis* bifid cipher, a type of cipher in cryptography...
anthers. The exine is finely reticulate and tectate. The pistilode is bottle-shaped and has pointed tips. The pistillate flowers are smaller, ovoid, and occasionally hairy; both sepals and petals are imbricate, the latter bearing scales. There are three united staminodes forming a small cup, the gynoecium
Gynoecium
Gynoecium is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves which evolved to form a closed structure containing the ovules...
is ovoid and uniovulate; the pendulous stigma has three lobes. The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
is egg-shaped with a wrinkly exterior, divided into lobed segments when dry, and mature at orange or red. The epicarp is fibrous, the mesocarp fleshy, covering a five-lobed seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
, resembling the dry fruit.