Chthamalus barnesi Achituv & Safriel, 1980

Trivedi, Jigneshkumar N., Doshi, Mahima, Patel, Krupal J. & Chan, Benny K. K., 2021, Diversity of intertidal, epibiotic, and fouling barnacles (Cirripedia, Thoracica) from Gujarat, northwest India, ZooKeys 1026, pp. 143-178 : 143

Chthamalus barnesi Achituv & Safriel, 1980 Figures 3F-H , 11

Examined material.

Five specimens (BD: 3.03-5.57 mm), LFSc.ZRC-160, Shivrajpur, Jamnagar District (22°20'03"N, 68°57'17"E), 17 February 2019, Gujarat, India, rocky shore, leg. M. Doshi.

Diagnosis

(modified from Shahdadi and Sari 2011). Shell orifices almost kite-shaped (Fig. 3F, G ). Tergum narrow with upper part broader than lower part and suture between tergum and scutum zigzag-shaped (Fig. 3H ). Scutum elongated and triangular and lateral depressor muscle pit distinct without crest (Fig. 3H ). Maxilla bilobed (Fig. 11A ). Maxillule not notched or possess very shallow notch (Fig. 11B ). Lower part of maxillule is setose. Mandible with four teeth (Fig. 11C ). Basal comb with rows of 16-23 short spines and 2-4 stout large spines at lower angle (Fig. 11D ). Mandibulatory palp with dense setae on all margins (Fig. 11E ). Labrum with numerous fine teeth present (Fig. 11F ). Cirrus I: anterior ramus (with seven or eight segments) longer than posterior (usually with 5-7 segments) (Fig. 11G ). Cirrus II: anterior ramus (with six-seven segments) longer than posterior (usually with 5-7 segments) (Fig. 11H ). Cirri III-VI: rami almost equal in size.

Remarks.

The examined specimen in the present study agree with the description given by Achituv and Safriel (1980) and Shahdadi and Sari (2011). Chthamalus barnesi forms part of the Chthamalus challengeri group and closely resembles C. moro Pilsbry, 1916, C. neglectus Yan & Chan, 2004, and C. challengeri Hoek, 1883, but can be differentiated based on the following characters: a depression towards the tergo-occludent corner of the scutum ( C. moro , lacks this depression, Southward and Newman 2003), the tergal margin is not straight (tergal margin straight in C. moro , Southward & Newman, 2003), the scutal margin of the tergum shows a deep articular furrow (scutal margin of tergum almost straight in C. neglectus , Yan & Chan, 2004), and the maxillule possess a very shallow notch (maxillule possesses a distinct notch in C. challengeri , Shahdadi & Sari, 2011).

Worldwide distribution.

The species has been reported from the Red Sea, Gulf of Aden, and Gulf of Oman including Yemen, Oman, Iran, Saudi Arabia ( Shahdadi and Sari 2011), and northwest India (present study).

Distribution in India.

This species is reported for the first time in India from the coastal regions of Gujarat.

Figures

Figure 3. A Tetraclita ehsani LFSc. ZRC- 184 on shores of Diu B Tetraclita ehsani, external and internal view of scutum and tergum C Tetraclitella karandei ASIZCR 000454 on shores at Diu D shell of T. karandei E Tetraclitella karandei external and internal view of scutum and tergum F Chthamalus barnesi on shores G close up view of C. barnesi LFSc. ZRC- 160 H Internal and external view of scutum and tergum of C. barnesi I Microeuraphia withersi LFSc. ZRC- 161 (BD: 6.01 mm) J internal and external view of scutum and tergum of M. withersi.

Figure 11. Chthamalus barnesi Achituv & Safriel, 1980. (BD: 4.21 mm), LFSc. ZRC- 160, Light microscopy on mouth parts A maxilla B maxillule C mandible D close up on the inferior angle of mandible E mandibulatory palp F labrum G cirrus II H cirrus III. Scale bars in µm.