Skip to main content

Stone pen in new genus Lithoptilum and sea pen in Anthoptilum, Calibelemnon removed

Stone pen in new genus Lithoptilum and sea pen in Anthoptilum, Calibelemnon removed

NEWS - Researchers report new analysis results that support the establishment of a new genus, Lithoptilum, to accommodate rock pens as a taxon close to Anthoptilum within the Anthoptilidae (Pennatuloidea) and require the deletion of the species Calibelemnon francei and the genus Calibelemnon within the Scleroptilidae.

Upasana Ganguly and Scott France of the University of Louisiana at Lafayette used a phylogenetic tree based on multilocus data and a single mitochondrial marker that showed all rock pens form a monophyletic clade within a larger clade representing the Anthoptilidae, deleting Calibelemnon (Scleroptilidae) and erecting the genus Lithoptilum.

Sea pens (Pennatuloidea) are a specialized group of octocorals that evolved to live anchored to the seafloor on soft sediments using their stalks as anchors, whereas rock-dwelling sea pens or rock pens use sucker-like stalks to attach to hard substrate surfaces, an adaptation previously unknown to sea pens.

Four species have now been identified as rock pens based on stalk morphology, three species within Anthoptilum and one within Calibelemnon. But this study found that the type specimen of Calibelemnon symmetricum (Nutting, 1908) is a colony with an elongated stalk, which is typical of soft-sediment sea pens, making the genus homogeneous.

Ganguly and France explored the geographic distribution and habitat depths using the NOAA Ship Okeanos Explorer and operated ROVs to record high-definition video to investigate the evolutionary origins of rock pens. They found thousands of colonies in the central Pacific Ocean at a depth of 450 meters. No such rock pen fields were observed in deeper waters.

Phylogenomic analyses were based on DNA sequences of ultraconserved elements (UCEs) and compared with trees constructed using mitochondrial genes. The ancestors of sea pens evolved along a single lineage that is sister to the lineage comprising the genus Anthoptilum. All rock pen species should be grouped into a new genus within Anthoptilidae.

Mitochondrial gene sequence analysis shows that the rock pen has the same gene sequence as Anthoptilum grandiflorum and Anthoptilum murrayi in the Octocoral B gene sequence. The arrangement is different from all other sea pens but matches that of bamboo corals (Keratoisididae). Among the 7 species that have been described in Anthoptilidae, 6 species have the same gene sequence.

Original research

Upasana Ganguly & Scott C. France (2024). Expanded distribution and a new genus for rock-inhabiting sea pens (Cnidaria, Anthozoa, Octocorallia, Pennatuloidea). Zootaxa, 5507 (1): 123-139, DOI:10.11646/zootaxa.5507.1.5

Popular Posts

Bugang (Clerodendrum calamitosum)

Bugang ( Clerodendrum calamitosum ) is a species of plant in the Lamiaceae family. It is an erect shrub, growing up to 1 meter tall, with cylindrical, green stems and white hairs. The leaves are opposite. The leaf blade is oval, wavy, with a central main vein with numerous pinnate minor veins, and serrated margins. The leaves are up to 9 cm long and 7 cm wide. The petiole is up to 2 cm long. The flowers are star-shaped, white, up to 3 cm in diameter and up to 6 cm in total length. The fruit is round, dark green, turning black when ripe. TAXON Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Magnoliopsida Order: Lamiales Family: Lamiaceae Subfamily: Ajugoideae Genus: Clerodendrum L. in Sp. Pl.: 637 (1753) Species: Clerodendrum calamitosum L. in Mant. Pl. 1: 90 (1767) HETEROTYPIC SYNONYMS Clerodendrum fastigiatum (W.Hunter ex Ridl.) H.J.Lam in Verben. Malay. Archip.: 317 (1919) Volkameria alternifolia Burm.f. in Fl. Indica: 137 (1768) Volkameria fastigiata W.Hunter...

Durian (Durio zibethinus)

Durian ( Durio zibethinus ) is a species of tropical plant in Malvaceae, an annual tree, everlasting green but there are certain times to grow new leaves after the fruiting period is over, popularly called "king of fruit" and considered a controversial fruit where many people like, but some others are even fed up with the scent. D. zibethinus grows to 25-50 m, reddish brown bark and irregular peeling, leafy and stretched canopy. The leaves are oval shaped to lanceolate, 10-15x3-4.5 cm, sitting alternately, stemmed, taper or blunt base and taper-pointed sloping, bright green upper side, the lower side covered with silver or golden scales. Flowers and fruit Flowers appear directly on the trunk or old branches at the proximal, clustered in panicles containing 3-10 florets or flat-shaped florets. Rounded flower buds, 2 cm in diameter and long stem. Tubular petals, 3 cm long, additional petals split into 2-3 round lobes. Crown shaped spatula with a length of 2 times the ...

Common sun skink (Eutropis multifasciata)

Kadal kebun or bengkarung or Mabuya multifasciata or common sun skink ( Eutropis multifasciata ) is a species of lizard in Scincidae, has a pattern of faint lines extending to the sides of the body, measuring 18 to 22 cm in length with a tail length of about 60% of the overall body and more many live on the ground. E. multifasciata has a sharp head with a very short neck and a square cross section. The upper part is dark brown or shiny grayish brown with a golden body side especially near the neck. Sometimes also decorated with small pale spots on the back. The lower neck is light brown and the abdomen to the anus is pale brown. The muzzle is reddish, the tail is the same color as the body, decorated with a faint dark line on the sides. The arms are also the same color as the upper body. Common sun skinks usually live on the edge of forests, gardens, rice fields and human settlements. They spend most of their time on the ground, usually in crevices and rocky cliffs as a place t...