Caecum draperi, Raines, 2020

Raines, Bret K., 2020, A Rosetta Stone for eastern Pacific Caecidae (Gastropoda: Caenogastropoda), Zootaxa 4827 (1), pp. 1-146 : 128-131

publication ID	https://doi.org/ 10.11646/zootaxa.4827.1.1
publication LSID	lsid:zoobank.org:pub:2CE528C2-DE07-4155-B37D-BE2C342A3901
DOI	https://doi.org/10.5281/zenodo.4457839
persistent identifier	https://treatment.plazi.org/id/03A3DF49-FF9D-FF03-FF44-F9F6FA8F395A
treatment provided by	Plazi
scientific name	Caecum draperi
status	sp. nov.

Treatment

Caecum draperi View in CoL species novum

Figures 111 View FIGURE 111 A–G, 112A–J, 113A–B, 126B

Brochina carpenteri — Lightfoot, 1993b: 82, fig. 30.

Type material. Holotype, SBMNH 637748 About SBMNH ; paratypes, SBMNH 637747 About SBMNH (4 figured); SBMNH 637749 About SBMNH (3 figured, 1 unfigured); LACM 3756 About LACM (2 figured).

Additional material examined. NHMLAC: LACM 1977-144.15, Chame Point, Panama Bay, Panama Prov., Panama, 6 sh. SBMNH: SBMNH 452501, Punta Chame, Panama Bay, Panama Prov., Panama, 6 sh; SBMNH 452539, Pier 18, Balboa, Panama Prov., Panama, 2 sh; SBMNH 452440, Pier 18, Balboa, Panama Prov., Panama, 2 sh; SBMNH 452441, Pier 18, Balboa, Panama Prov., Panama, 3 sh; SBMNH 620531, Playa Venado, Panama Prov., Panama, 20 sh; SBMNH 637751, Fuerte Amador, Panama, intertidal, 1 sh; SBMNH 637746, Punta Chame, Panama Bay, Panama Prov., Panama, 3 sh.

Type locality. Chame Point , Panama Bay, Panama Prov., Panama.

Diagnosis. Teleoconch subcylindrical, with slight increase in diameter from posterior end to aperture. Surface smooth with 12–16 large, irregularly spaced, axial ribs, which increase in strength aperturally, semi-translucent to creamy white in color. Septum mucronate, moderately inflated, with low blunt mucro. Aperture simple, rather thin. Periostracum thin, yellowish.

Description. Protoconch and teleoconch I unknown. Teleoconch II surface smooth ( Fig. 112D View FIGURE 112 ), transition to teleoconch III marked by slight incised axial line ( Fig. 112A View FIGURE 112 ). Teleoconch III smooth with irregularly spaced, axial ribs near apertural end ( Figs. 112B View FIGURE 112 ), transition to teleoconch IV marked by suture ( Fig. 113A View FIGURE 113 ). Teleoconch IV with identical characters as previous stage, transition to teleoconch V marked by suture ( Fig. 113A View FIGURE 113 ). Teleoconch V smooth with large, irregularly spaced axial ribs ( Figs. 112 View FIGURE 112 G–H), transition to teleoconch VI marked by suture, followed by increase in diameter ( Fig. 112I View FIGURE 112 ). Teleoconch VI (last growth stage) large for genus [Tol 4.90–5.18 mm], tubular, rather thin, mildly and regularly arched [Larc: 1.81–2.00 mm; Arc: 0.40–0.53 mm], subcylindrical, with slight increase in diameter from posterior to aperture, semi-translucent to creamy white ( Figs. 111A View FIGURE 111 , 112J View FIGURE 112 ). Axial sculpture of 12–16 large, rather irregularly spaced axial ribs, increasing in strength aperturally ( Fig. 112J View FIGURE 112 ). Surface smooth with thin axial lines overall ( Fig. 112G View FIGURE 112 ). Posterior [Dpe: 0.80–0.82 mm] with rather thick edge, squared shoulder ( Fig. 111E View FIGURE 111 ). Septum mucronate, moderately inflated ( Fig. 112J View FIGURE 112 ). Mucro conical, low, blunt, positioned near dorsal margin ( Fig. 112C View FIGURE 112 ). Aperture [Da: 0.90–0.95 mm] simple, rather thin ( Fig. 111E View FIGURE 111 ). No varix. Lip smooth ( Fig. 111E View FIGURE 111 ). Periostracum thin, smooth, yellowish ( Fig. 111A View FIGURE 111 ). Operculum thick, multi-layered, tapering, light brown, interior surface with central subcylindrical cusp ( Fig. 111F View FIGURE 111 ); exterior surface with 6–7 concentric rings ( Fig. 111G View FIGURE 111 ). Conceptual reconstruction of growth stages shown in Fig. 113A View FIGURE 113 .

Etymology. The species is named in honor of the late Bertram “Bert” C. Draper (1904 – 2000), for his work on Caecidae while a Museum Associate with the Los Angeles County Museum of Natural History.

Distribution and Habitat. From Chame Point, Panama Bay, Panama to Carrillo Peninsula de Nicoya, Costa Rica. Intertidal to subtidal. Uncommon on algae and coarse sand substrates.

Remarks. Lightfoot (1993b) misidentified Caecum draperi as C. carpenteri = C. adamsi from Panama. However, C. draperi can be distinguished by its well-defined undulating axial ribs, lack of microsculpture, and unique multi-layered operculum. And as previously noted, the range of C. adamsi is restricted to southern California south to the Gulf of California, Mexico. Lightfoot also noted examining three specimens from Costa Rica. Given the close proximity to the type locality, it is reasonable to deduce these three specimens are C. draperi as well.