Martesia striata (Linnaeus, 1758)

Mahapatro, Debasish, Sharma, Satyabrata Das & Kadam, Surendra S., 2020, On the record of two species of the family Pholadidae (Martesia fragilis and Martesia striata) off Dhamara Estuary (Odisha), Bay of Bengal, Records of the Zoological Survey of India 120 (4), pp. 351-356 : 354

2. Martesia striata (Linnaeus, 1758) ( Figure 4 & 5A )

1758. Pholas striata Linnaeus, Syst. Nat. ed. 10: 669.

2017. Martesia striata : Subba Rao, Rec. zool. Surv. India., Occ. Paper, 375: 348.

Material examined: Five live specimens from Dhamara estuarine systems from a depth of 2 meter of Dhamara estuary (Figure-1, Point-1, 20°45’29”N 87°01’39”E).

Diagnosis: Main body subovate; shell divided by a radial groove; robust; posterior part brittle; posterior extension narrower and irregular; inequilateral beaks close to the anterior part; tumid at umbos; anterior broadly rounded with initial pedal gape filled by the callum, large subcircular mesoplax; dorsal area behind mesoplax covered by a long lanceolate metaplax; posterior ventral region covered by a long lanceolate hypoplax ( Turner & Santhakumaran, 1989; Oliver, 1992; Subba Rao, 2017).

Distribution: India: Odisha coast (Dhamara estuarine system, Subarnarekha estuary), Andaman and Nicobar Is., Maharashtra ( Bombay), Gujarat (Gulf of Kutch), West Bengal (Kidderpore docks, Port Canning) Andhra Pradesh (Visakhapatnam, Godavari and Krishna estuaries); Tamil Nadu (Madras, Poto Novo, Tuticorin, Krusadai Island, Pamban); Kerala ( Cochin, Kayankulam); Karnataka ( Subba Rao, 2017). Elsewhere: Eastern Pacific; Indo- Pacific, West Atlantic; Widely distributed in Temperate and Tropical waters.

Remarks: This species is widely distributed along the coastline of India, estuarine systems & creeks. It frequently attacks the live and dead mangrove timber; makes burrow into soft clay, sand stone, wood and can tolerate a wide range of salinity fluctuation ( Subba Rao, 2017). The major morphological differentiation between M. striata and M. fragilis can be well visualised from the Figure 5 . It is evidenced that the overall body shape of M. fragilis is much straighter and more fragile than the M. striata . The posterior part of M. striata is narrow and irregular as compared to former one ( Turner & Santhakumaran, 1989). The comparison of mesoplax and metaplax of M. fragilis and M. striata which is considered as one of the important tool for species level identification can also be depicted from Figure 5 .

Figures

Figure 4. A. Image showing dorsal side and B. Ventral side of Martesia striata collected from off Dhamara estuary.

Figure 5. Image showing morphological differences between Mesoplax and Metaplax of Martesia striata from estuary and B. Martesia fragilis from offshore of Dhamara respectively.