''Mesospora negrosensis'' is a species of macroalga occurring in the western Atlantic.

Taxonomy

''Mesospora negrosensis'' is one of nine species under the genus based on the record of AlgaeBase, of which only seven are accepted taxonomically based on literature. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''negrosensis'' was derived from where the locality of the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

species was first collected (Lalaan, Negros Oriental, Philippines).

Morphology

The genus ''

Mesospora ''Mesospora'' is a genus of macroalgae that was described by Anna Weber-van Bosse in 1911. Although considered a taxonomic synonym of ''Hapalospongidion'', the World Register of Marine Species cites six accepted species of the genus. Description ...

'' as described by Anna Weber-van Bosse (1911) is a crustose brown macroalga with the following characteristics: a saxicolous habitat, gelatinous crustose thallus, adherent to the substrate without rhizoids, several cells thick basal layer, unbranched erect free filaments, intercalary plurilocular reproductive structures uniseriate or biseriate and unilocular reproductive structures stalked and borne laterally at base of erect vegetative filaments. ''Mesospora'' is said to be morphologically similar to '' Diplura''. Their difference lies in the number of

chloroplast A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in ...

s per cell. The ''Mesospora'' has a single chloroplast per cell, a one-celled sterile tip of the erect filament and unilocular sporangia, while the ''Diplura'' has several chloroplasts per cell and lacks unilocular sporangia. The plurilocular reproductive structures of ''M. negrosensis'' are described as being mostly uniseriate while '' M. schmidtii'' were described as biseriate and triseriate and compared to genus ''Diplura'', where the plurilocular sporangia are often biseriate. ''M. negrosensis'' was said to be plurilocular sporangia and non-unilocular as compared to ''M. schmidtii'', which contains unilocular sporangia.

Distribution

The holotype was collected on a rock at Lalaan, Negros Oriental, Philippines. Poong et al., in 2013 collected a specimen from the water of Malaysia.

Ecology

''Mesospora negrosensis'' are usually found attached to small igneous rocks at the mid-intertidal region with no other macroalgae present. Nearby large rocks were covered with patches of '' Lyngbya'' and other unbranched filamentous cyanobacteria. The area is said to be nutrient-rich due to runoff water from agricultural lands and storm drainage.

References

{{Taxonbar, from=Q29476585 Ralfsiales Flora of the Philippines Plants described in 1996