Benthic harpacticoid copepod diversity and their adaptations to the coral area of Pulau Tioman

Abstract

The study is carried out to investigate the identity of harpacticoid species, morphology and ultrastructure which might serve as their living strategy in adapting the coral environment. Field samplings were carried out between August, September and October 2017 at six selected stations, which are Salang, Tulai Station 1, Tulai Station 2, Batu Malang, Renggis and Soyak. Sediment cores were obtained by scuba divers using transparent hand core (3.5 cm mouth diameter) which later been preserved with 10% formalin added with Rose Bengal. The meiobenthos were extracted from the sediment through decantation and sieving process using 500 microns and 63 microns mesh sieve. Harpacticoid specimen were dissected and prepared for taxonomic examination with the help of Lucida camera attached to a compound microscope. The ultrastructure of the species was determined from the micrograph resulted from Scanning Electron Microscope examination. Analysis on the diversity of the species found in the study area was done by determining the Shannon’s Weiner (H’), Margalef (d) and Evenness Pielou, (J’). A total of 14 harpacticoid species representing 9 genera from the family of Dactylopusiidae (Dactylopusia sp.), family Ectinosomatidae (Ectinosoma sp.), family Miraciidae (Robertgurneya smithi, Typhlamphiascus lamellifer, Typhlamphiascus blanchardi and Delavalia clavus), family Laophontidae (Laophonte cornuta, Laophonte expansa, Quinquelaophonte quinquespinosa and Asellopsis sp.), family Tetragonicipitidae (Phyllopodopsyllus sp. 1 and Phyllopodopsyllus sp. 2) and family Canuellidae (Canuellina nicobaris and Brianola sp.) were discovered from the sampling sites. Based on taxonomic identification, the harpacticoid species in Pulau Tioman did not show a marked different from other area except presence row of spinules on the surface of swimming leg in Devalia clavus and Robertgurneya smithi, conical shape of furcal rami in Typhylamphiascus lamellifer, five setae ornamented the caudal rami of Quinquelaophonte quinquespinosa and 7 arthrites on maxillule on Canuellina nicobaris. The micrograph revealed features like strong and jagged claw of maxilliped of Asellopsis sp., and; thick and pitted integuments ornamented the cephalotorax and somites of Laophonte cornuta and Laophonte expansa. Harpacticoids in Renggis were significantly related with the hard coral (p = 0.030, p <0.05), sand (p = 0.046) and dead coral (p = 0.031, p, 0.05), while species diversity of harpacticoid copepods from the Tioman coral reef area is considered high with the H’ value > 1.8, d > 1.5 and J > 1.8. The taxonomic data and biodiversity could be further through field experimental approach to understand the harpacticoid strategy towards environmental factor.