Tetraclita kuroshioensis Chan, Tsang & Chu, 2007

Pochai, Ashitapol, Kingtong, Sutin, Sukparangsi, Woranop & Khachonpisitsak, Salinee, 2017, The diversity of acorn barnacles (Cirripedia, Balanomorpha) across Thailand's coasts: The Andaman Sea and the Gulf of Thailand, Zoosystematics and Evolution 93 (1), pp. 13-34 : 18-19

Tetraclita kuroshioensis Chan, Tsang & Chu, 2007 Figure 6 ; Suppl. material 1; Tables 2, 3

Tetraclita squamosa viridis : Hiro 1936: 635; 1937: 469; 1939: 271.

Tetraclita squamosa squamosal : Utinomi 1968: 178.

Tetraclita pacifica Chan et al., 2007b: 88.

Non-type material examined.

Andaman Sea: 2 specimens, Phang-nga province , Khura Buri district, Ao Khoei beach, 30.VII.2015, A. Pochai (BUU16.TC.TK01-02) . 3 specimens, Phang-nga province , Takua Thung district, Na Tai beach, 16.V.2015, A. Pochai (BUU16.TC.TK03-05) . 2 specimens, Phuket province, Mueang Phuket district, Ao Yon beach, 15.VII.2015, A. Pochai (BUU16.TC.TK06-07) . 3 specimens, Phuket province, Katu district, Kalim beach, 15.VII.2015, A. Pochai (BUU16.TC.TK08-10) .

Gulf of Thailand: 3 specimens, Prachuap Khiri Khan province, Bang Saphan district, Ban Krut beach, 06.IX.2015, A. Pochai (BUU16.TC.TK11-13) . 3 specimens, Chon Buri province, Ko Si Chang district, Ko Kham Yai beach, 05.VII.2015, S. Khachonpisitsak (BUU16.TC.TK14-16) .

Description.

Peduncle absent; base membranous; shell greyish black to purplish-grey with 4 plates (1 carina, 2 latus, 1 rostrum), parietes conical, plates inseparable, 7-8 rows of parietal tubes (parietes multiple tubiferous), external surface with mosaic scales pattern radiating randomly from base to apex, internal surface of parietes smooth and white with dark grey striations around aperture. External surface of operculum mixed grey and yellowish-light brown, internal surface of operculum greyish-dusky green. Scutum bigger than tergum, scutum triangular, external surface of scutum with horizontal striations, occludent margin of scutum with obvious shallow and rough teeth, short articular ridge-basal margin, angle between basal margin and tergal margin is quite perpendicular. Tergum higher than wide, basi-scutal angle 158°, tergum with broad spur, spur angle 30°. Mandible with 4 big teeth, 1st tooth smaller; maxillule not notched with 11 setae; labrum with 5 small teeth on each side; cirri I possessing serrulate setae.

Distribution.

Tetraclita kuroshioensis is reassigned the name from Tetraclita squamosa which were collected from Taiwan, and Okinawa and Honsu of Japan, and Tetraclita pacifica . The distribution of this species occurs in broad area along north-west Pacific region ( Chan et al. 2007a, b; Chan 2009). In this present study, the species distribution occurs along littoral intertidal zones in both the Andaman Sea (Ao Yon, Ao Khoei, Na Tai, and Kalim) and the Gulf of Thailand (Ban Krut and Ko Kham Yai).

Remark.

Tetraclita kuroshioensis is quite similar to Tetraclita singaporensis in following characteristics: tergum without beak and with wide spur, scutum with short articular ridge-basal margin. However, angle between tergal margin and basal margin of Tetraclita kuroshioensis is more perpendicular (90°) or shaper while that of Tetraclita singaporensis is curved.

Figures

Figure 6. Tetraclita kuroshioensis collected from (BUU 16. TC. TK 01) from Na Tai beach, Phang-nga. A. Dorsal and ventral view of external shell, B. External (left panel) and internal (right panel) view of tergum (upper panel) and scutum (lower panel), C-F. Light microscopy on mouthparts, C. Labrum, D. Close up on the teeth of the labrum, E. Mandible, F. Close up on the lower margin of mandible. C-F. Scale bars in µm.