Octomeris brunnea Darwin, 1854

Chan, Benny K. K., Tsao, Yao Feng & Ganmanee, Monthon, 2020, Morphological and molecular evidence support the intertidal barnacle Octomeris intermedia Nilsson-Cantell, 1921 (Thoracica, Chthamalidae) as a valid species in Indo-Pacific waters, ZooKeys 914, pp. 1-31 : 1

publication ID	https://dx.doi.org/10.3897/zookeys.914.49328
publication LSID	lsid:zoobank.org:pub:6EC16BE4-BC22-4559-9163-7F406EB24597
persistent identifier	https://treatment.plazi.org/id/22EBAAB5-3E73-5B62-BFB7-7FECE103B54A
treatment provided by	ZooKeys by Pensoft
scientific name	Octomeris brunnea Darwin, 1854
status

Treatment

Octomeris brunnea Darwin, 1854 Figures 2G View Figure 2 , 3 View Figure 3 , 4 View Figure 4 , 5 View Figure 5 , 6 View Figure 6 , 7 View Figure 7 , 8 View Figure 8 , 9 View Figure 9 , 15D-F View Figure 15 , 16D-F View Figure 16

Octomeris brunnea Darwin, 1854: 484, pl 20, figs 3a, b; Weltner 1897: 274; Gruvel 1905: 197, fig. 217; Nilsson-Cantell 1921: 299, figs 58, 59, pl 3, fig. 7; -1931: 108; - 1932, 14; Hiro 1939: 252, figs 3-4, 6a, b; Utinomi 1949: 25; -1958: 307; Endean, Kenny and Stephenson 1956: 122, 127, tab. 1; Endean, Stephenson and Kenny 1956: 332, 336, app II; Pope 1965: 20, figs 1c, 2b, pl 1: figs 3, 6; Newman and Ross 1976: 40; Poltarukha 1996: 992; Liu and Ren 2007: 283, fig. 123; Chan et al. 2009: 153: figs 128-130; Jones 2012: tabs 1, 2.

Materials examined.

ASIZCR-000431. Intertidal rocks at General Rock, Green Island, Taiwan (22°40.35'N, 121°29.45E, 16 August 2019, 1 specimen). CEL-Octm_GI_01. Intertidal rocks at General Rock, Green Island, Taiwan (22°40.35'N, 121°29.45'E, 16 August 2019, 5 specimens). CEL-KT-131. Intertidal rocks at Hai Kou, Kenting, Taiwan (22°06.06'N, 120°42.56'E, 4 Dec 2007, 7 specimens). CEL-LAN-178. Intertidal rocks at southern Lanyu, Lanyu, Taiwan (22°00.82'N, 121°33.94E, 19 June 2019, 2 specimens). CEL-Octm_sp_01. Intertidal rocks at Shi-Ti-Ping, Hualien, Taiwan (23°28.56'N, 121°30.41E, 13 May 2009, 1 specimen). CEL-Octm-G05. Intertidal rocks at Puerto Galera, Philippines (02 June 2009, 20 specimens). CEL-Octm-G23. Intertidal rocks at Varadaro Point, Puerto Galrea, Philippines (02 June 2009, 1 specimen).

Diagnosis.

Shell eight plated, conically depressed. Shell brown, surface with longitudinal furrows and tergo-scutal junction straight in young and uneroded specimens. Shell gray, surface smooth and tergo-scutal junction sinuous in old and eroded specimens. Maxillule with deep notch at upper 1/3 of cutting edge, lower 1/3 strongly protruded, cutting edge clearly divided into upper, middle, and lower region by the clear notch and protrusion of lower margin.

Description.

Shell 8 plated, composed of piece of rostrum (R), carina (C), paired rostro-lateral (RL), carino-lateral (CL) and lateral (L) (Figs 2G View Figure 2 , 4A, B View Figure 4 ). Shell conically depressed. Shell brown, surface with longitudinal furrows and tergo-scutal junction straight in young and uneroded specimens (Figs 3 View Figure 3 , 4A View Figure 4 ). Shell grey, smooth, tergo-scutal junction sinuous in old and eroded specimens (Figs 3 View Figure 3 , 4B View Figure 4 ). Sutures of shell plates serrated (Figs 2G View Figure 2 , 4A, B View Figure 4 ). In young and uneroded specimens, scutum triangular, outer surface with horizontal growth lines (Fig. 4A View Figure 4 ). Scutum inner surface brown, tergal and occludent margins straight in young specimens, basal margin slightly convex (Fig. 4A View Figure 4 ). Tergal margin straight, with conspicuous articular ridge. Adductor muscle scar shallow (Fig. 4A View Figure 4 ). In older and eroded specimens, tergal margin of scutum strongly sinuous, adductor muscle scar deep (Fig. 4B View Figure 4 ). Tergum with basal margin strongly bended in an angle, scutal margin straight with deep articular ridge in young specimens, depressor muscle distinct, muscle crests prominent and extended slightly out of the carinal margin of tergum (Fig. 4A View Figure 4 ). In older and eroded specimens, the scutal margin strongly concaved (Fig. 4B View Figure 4 ).

Cirrus I rami unequal (Fig. 5A View Figure 5 ). Posterior ramus short, six-segmented. Anterior ramus seven-segmented. All segments height greater than width (Fig. 5A View Figure 5 ). Bidentate serrate setae and simple setae present. Bidentate serrate setae appear up to seven segments in anterior ramus and present up to first three distal segment in posterior ramus (Fig. 5B-D View Figure 5 ). Cirrus II, posterior ramus seven-segmented, anterior ramus eight-segmented. Bidentate serrate setae present up to seven segments in anterior ramus and up to first four distal segments in posterior ramus (Fig. 5E-H View Figure 5 ). Cirri III to VI similar in morphology, long and slender (Figs 6 View Figure 6 , 7 View Figure 7 ). Cirrus III, posterior and anterior rami 12 segmented (Fig. 6A-D View Figure 6 ). Cirri IV and V, posterior and anterior rami 15-segmented (Figs 6E-H View Figure 6 , 7A-C View Figure 7 ). Dorsal surface of cirri IV- VI has small spines (Figs 6G View Figure 6 , 7F View Figure 7 ). Cirrus VI with 16 segmented rami (Fig. 7D-E View Figure 7 ). Intermediate segments of cirri III and VI with three pairs of long and one pair of short simple setae (Figs 6B, F View Figure 6 , 7B, E View Figure 7 ). Distal segments of cirrus III bear two pairs of long and one pair of short setae (Figs 6C, D, H View Figure 6 , 7C View Figure 7 ). Caudal appendage absent. Penis short, tip with a few simple setae (Fig. 7G, H View Figure 7 ).

Maxilla subtriangular, distal lobe prominent and proximal lobe flat, shallow notch present in inner margin between the two lobes (Fig. 8A View Figure 8 ), inner and outer margin with serrulate setae (Fig. 8B-D View Figure 8 ). Maxillule with a deep notch on upper 1/3 and lower 1/3 of cutting edge. Cutting edge obviously divided into three distinct portions. Cutting edge above upper notch with two large and a few setae (length of setae ranges from 80-100 μm); middle portion of cutting edge has six setae; 1/3 of lower portion of cutting edge has eight short setae (Fig. 8E-H View Figure 8 ). Mandibles with three teeth, cutting edge of first tooth smooth, second tooth with one or two spines, third tooth with a few spines on cutting edge (Fig. 9A-D View Figure 9 ). Mandibular palp elongated, with serrulate setae on outer margin (Fig. 9E, F View Figure 9 ). Cutting margin of labrum concave, with small fine teeth (Fig. 9G, H View Figure 9 ).

Distribution.

Southern Japan, Taiwan, Philippines, east coast of Queensland in Australia, Santa Cruz and New Hebrides (based on specimens in Australian Museum stated in Pope, 1965).