Pectinia
Blainville, 1825, p. 201
Pectinia was originally described by Oken (1815). According to ICZN Opinion 417 (September 1956), the names originally proposed by Oken (1815) are rejected. Therefore authorship is assigned to the second person who used the name.
Type Species
Madrepora lactuca Pallas, 1766, p. 289; Subsequent Designation Vaughan, 1901, p. 15
Type Specimen: Neotype; NHMUK 1987.6.1.1; Verified; Dry Preserved
Type Locality: 'Mare Americanum?' (Pallas, 1766, p. 289), 'Samboanga Atoll, Philippines' (specimen label; probably incorrect) (Recent)
The holotype is lost (Cornelius and Wells, 1988, p. 85).
Classification
Synonyms
Diagnosis
Colonial, with intracalicular budding only. Corallites polymorphic and organically united; monticules absent. Coenosteum costate, extensive amount (≥ corallite diameter). Calice width medium (4–15 mm), with medium relief (3–6 mm). Costosepta confluent. Septa in 3 cycles (24–36 septa). Free septa present but irregular. Septa spaced < 6 septa per 5 mm. Costosepta unequal in relative thickness. Columellae trabecular and spongy (> 3 threads), < 1/4 of calice width, and discontinuous among adjacent corallites (lamellar linkage). Paliform (uniaxial) lobes weak or moderate. Epitheca absent and endotheca abundant (vesicular). Tooth base at mid-calice circular. Tooth tip at mid-calice irregular; tip orientation perpendicular to septum. Tooth height medium (0.3–0.6 mm) and tooth spacing medium (0.3–1 mm), with no more than 6 teeth per septum. Granules scattered on septal face; irregular in shape. Interarea formed by horizontal bands. Walls formed by dominant paratheca; abortive septa absent. Thickening deposits micro-fibrous. Costa center clusters not distinct; medial lines strong. Septum center clusters not distinct; medial lines strong. Transverse crosses absent. Columella centers clustered.
Description
'Polypier formé de feuilles minces, plus ou moins roulées, avec des étoiles des deux côtés, et il y place à peu près les mêmes espèces.' (de Blainville, 1825: 201)
Comparisons
Pectinia and Mycedium share all morphological traits examined here, resulting in a polytomy on the phylogeny. Physophyllia also scored identically for macromorphology. There are thus no apomorphies yet for Pectinia, but its members generally have thin and acute laminae that project upward, lacking the large rounded vesicular ridges separating adjacent calices and inclined corallites as seen in Physophyllia and Mycedium respectively. Synapomorphies for the well-supported Pectinia + Mycedium clade include organically united and polymorphic corallites, extensive coenosteum (≥ corallite diameter), unequal costosepta thickness, discontinuous columellae (lamellar linkage), ≤ 6 teeth per septum, interarea made up of horizontal bands, and presence of micro-fibrous deposits. Note that quantitative measurements were made on peripheral corallites; structures of the central corallite are not indicative of the main parts of the colony.
Remarks
It is the type genus of Pectiniidae Vaughan and Wells, 1943: 196, which also contains Echinophyllia, Mycedium, Oxypora, and Physophyllia, among the living scleractinians. Recent broad-scale molecular phylogenetic studies have placed the clade Echinophyllia + Oxypora within Lobophylliidae, while Pectinia and Mycedium form a monophyletic group in Merulinidae (Fukami et al., 2004, 2008; Arrigoni et al. 2012). Physophyllia is expected to be a close relative of Pectinia based on macromorphology (see remarks for Physophyllia below). Pectinia is often associated with Oulophyllia (e.g. Veron, 2000, vol. 2: 348), the latter being described as having comparatively lower walls and more spongy columellae (Milne Edwards and Haime, 1848, vol. 27: 492). As noted above, laminae of the former are probably not homologous to the walls of Oulophyllia, but the two genera are indeed closely related, and together with Caulastraea and Mycedium form a well-supported molecular clade (Fukami et al., 2008; Huang et al., 2011; Arrigoni et al., 2012).
Distribution
- East Asia; Pleistocene - Holocene
- East Asia; Pleistocene
- Indian Ocean; Recent
- Western Pacific; Recent
- Central Pacific; Recent
- East Asia; Holocene
Source: Paleobiology database (accessed June 18th, 2012), Veron (2000). Historical distribution: Recent., IndoPacific (Wells, 1956). Distribution compiled by Matthew Tibbits. Recent: Pectinia is widely distributed on reefs of the Indo-Pacific, but distinctly absent in the northwestern Indian Ocean and the Red Sea, as well as east of Samoa in central Pacific.This page has been in preparation since 06-Oct-2009 22:29
This version was contributed by Danwei Huang on 05-Feb-2014 23:27.
Page authors are: Ann Budd Danwei Huang. Please contact the editor if you would like to contribute to the diagnosis of this taxon.
The editor is: Ann Budd
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