Diaphanosoma sarsi Richard, 1894

Pascual, Jhaydee Ann F., Rizo, Eric Zeus C., Han, Boping, Dumont, Henri J. & Papa, Rey Donne S., 2014, Taxonomy and distribution of four Cladoceran families (Branchiopoda: Cladocera: Moinidae, Bosminidae, Chydoridae and Sididae) in Philippine inland waters, Raffles Bulletin of Zoology 62, pp. 771-794 : 784-787

Diaphanosoma sarsi Richard, 1894

Specimen examined. Ten parthenogenic female, eight mounted specimens ( UST-ZRC 0097 , 0099 - Lake Paoay, Ilocos Norte; 0098 - Lake Danao, Camotes Island , Cebu; 0100- Lake Buhi , Camarines Sur; 0101- Lake Tambo , Tarlac; 0102- Lake Nalbuan , Cagayan; 0103, 0104- Lake Sampaloc , Laguna), two were damaged beyond repair .

Description. Diaphanosoma sarsi is the most well-distributed cladoceran found throughout the Philippines. It is found in almost all types of water bodies from swamps to a few river systems. This species is distinguished by a small roundish rectangular head with sloping dorsal side. Its eye occupies almost the whole area of the head. The carapace of D. sarsi is situated high on its body with its ventral parts forming a broad free flap. Its ventral margins have around 13–40 small denticles. It is fairly common throughout inland water bodies especially in lakes and reservoirs in the tropics except Africa ( Fernando, 2002). In the Philippines it co-exists with three other species of Diaphanosoma ( Figs. 27 , 28 ).

Distribution. Ilocos Norte: Lake Paoay; Cagayan: Lake Nalbuan, Lake Nagatutuan Lake, Lake Bangalau; Benguet: Ambuklao dam; Kalinga: Fish pond in Laoagan Resort Inn; Pampanga: Candaba swamp; Tarlac: Lake Tambo; Zambales: Lake Mapanuepe; National Capital Region (NCR): Pasig River, Marikina River; Laguna: Lake Bunot, Lake Yambo, Lake Mohicap, Lake Pandin, Lake Sampaloc, Lake Tadlak, Lake Kalibato, Lake Lumot-Mahipon, Lake Caliraya, Laguna De Bay; Batangas: Lake Taal; Camarines Sur: Lake Baao, Lake Buhi; Sorsogon: Lake Bulusan; Oriental Mindoro: Lake Naujan; Negros Oriental: Lake Balinsasayao; Leyte: Lake Danao, Lake Bito; Bohol: Malinao Dam; Agusan del Norte: Agusan River; Lanao del Norte:Agus IV Dam, Tubud- Mayahay River; Bukidnon: Lake Apo, Lake Pulangi, Lake Pinamaloy; South Cotabato: Lake Lahit ( Fig. 23 )

Remarks. Species is found in tropical and sub-tropical Asia. Populations have been found in Nepal, Eastern China, Australia, New Guinea, New Caledonia, New Hebrides, Guam and few sites in tropical Africa. It can be found in a wide range of water bodies from large ancient lakes to rice fields. Common sidid found in lotic ecosystems. Prefers shallow waters with heavy vegetation but can also be observed in the limnetic zones of lakes. They are more sensitive to physico-chemical parameters in comparison with other Diaphanosoma species. D . sarsi has a noticeable sloping dorsal portion of its head that can easily differentiate it from other closely related species.

Figures

Fig. 27. Diaphamosoma sarsi, parthenogenetic female; A, habitus; B, postero-ventral valve margin; C, distal part of first segment of upper 2-segmented antennal branch; D, post abdomen.

Fig. 28. Scanning electron micrographs of Diaphanosoma sarsi. A, habitus; B, antennule.

Fig. 23. Distribution of family Sididae based on recently collected samples (2013) and stored samples in the UST ZRC.