Megabalanus zebra (Darwin, 1854)

Pitriana, Pipit, Valente, Luis, von Rintelen, Thomas, Jones, Diana S., Prabowo, Romanus E. & von Rintelen, Kristina, 2020, An annotated checklist and integrative biodiversity discovery of barnacles (Crustacea, Cirripedia) from the Moluccas, East Indonesia, ZooKeys 945, pp. 17-83 : 17

Megabalanus zebra (Darwin, 1854) Figure 27a-c , Table 1: species no. 98

Balanus tintinnabulum var. (4) zebra Darwin, 1854: 195. pl. 1 fig. g.

Balanus tintinnabulum zebra : Pilsbry 1916: 57, pl. 10 figs 2, 3; Stubbings 1967: 264; Dong et al. 1982: 86, fig. A-C.

Balanus tintinnabulum var. zebra Karande & Palekar, 1966: 143, pl. I, fig. 2.

Megabalanus zebra : Newman & Ross, 1976: 69; Henry and McLaughlin 1986: 47, figs 2f, 4j-k, 12e-l; Pitombo 2004: 275; Chan et al. 2009a: 265, fig. 232; Pitombo et al. 2017: 135, figs 2, 4, 5, 6, 7, 8.

Material examined.

Ambon Island: 4 specimens, MZB Cru Cir 068, Galala, 3°41'22.2"S, 128°10'52.6"E, coll. P. Pitriana & D. Tala, 6 Sep 2016; 4 specimens, MZB Cru Cir 069, Laha, 3°43'22.5"S, 128°05'02.5"E, coll. P. Pitriana & D. Tala, 5 Sep 2016.

Diagnosis.

Parietes reddish purple with strong longitudinal white ribs; radii and sheath dark purple to reddish brown; scutum with narrow tergal segment slightly inflected; tergum approximately as wide as scutum, crest for depressor muscle prominent.

Synoptic Description.

Shell conic, six-plated; parietes smooth, purple with well-developed white ribs and dark purple interspaces; radii wide, summits horizontal, white with dark purple spots on proximal side (Fig. 27a ); orifice rhomboidal; scutum triangular, external surface withe intersecting horizontal and longitudinal striations; tergum triangular, white with purple spots in some areas, scutal margin slightly curved, basal margin inclined, spur short (Fig. 27b, c ); mandible with five teeth, labrum with deep cleft, three teeth on each side. Basal length 5.4-19.0 mm, basal width 5.0-20.0 mm, height 4.4-13.1 mm. Orifice length 3.1-7.6 mm, orifice width 1.7-6.2 mm (measurements for eight specimens are presented in Suppl. material 1: Table S26).

Distribution.

Megabalanus zebra is a well-known fouling species of ship hulls, floating structures, moveable oil platforms, etc., and has been widely recorded from the Atlantic Ocean; W Africa; Indo-west Pacific: Indian Ocean; Australia; Thailand; China; Philippines; Taiwan ( Pilsbry 1896, 1916; Stubbings 1961; Karande and Pakelar 1966; Foster and Willan 1979; Chan et al. 2009a; Jones and Hosie 2016; Pitombo et al. 2017). In this study, Megabalanus zebra was found on Ambon Island (at Galala and Laha) on stones and the capitulum of Lepas anserifera (a map with the occurrence of Megabalanus zebra in the Moluccas is shown in Suppl. material 1: Fig. S1).

Remarks.

Megabalanus zebra can be distinguished from other species in the Megabalanus group by, for example, the inflection of the tergal segment of the scutum and the position of the spur ( Henry and McLaughlin 1986). M. zebra can also be differentiated by an intermediate shape of the tergum and scutum compared to M. tintinnabulum and M. coccopoma ( Pitombo et al. 2017).

Figures

Figure 27. Megabalanus zebra (Darwin, 1854) (MZB Cru Cir 068 - 3) a upper view b external view of scutum and tergum c internal view of scutum and tergum. Scale bars: 4 mm (a); 2 mm (b-c).