Unraveling Cryptic Diversity in the Indo-West Pacific Gastropod GenusLunella(Turbinidae) using Elliptic Fourier Analysis^*

Abstract

Morphological variation in shell shape was quantitatively evaluated among newly identifi ed cryptic species in two species complexes (coronata and cinerea groups) belonging to the gastropod genus Lunella (Turbinidae) using elliptic Fourier descriptors (EFDs). Sympatric species of the coronata group show greater phenotypic diversity than the entirely allopatric cinerea group. We suggest that if morphological divergence is driven most strongly in sympatry, cryptic species are more likely to occur in taxa with allopatric speciation. Discriminant analysis showed that one species (L. aff. coronata ophiolite) was signifi cantly different and could be distinguished from its two sister species (L. coronata (Gmelin, 1791), L. aff. coronata Oman) by shell outline with a high degree of success. In pairwise analyses two pairs from the cinerea group were also signifi cantly different and species could be determined with a modest degree of success: L. aff. cinerea Fiji with L. aff. cinerea SW Pacifi c and L. aff. cinerea Indian Ocean with L. aff. cinerea central Indo-West Pacifi c (cIWP). The remaining species could not be accurately identifi ed by shell shape alone in this study. We also used a combination of shell shape and shell sculpture to determine that the coronate form of L. coronata, which occurs along the east coast of Africa and along the Arabian Peninsula into India, corresponds to L. coronata sensu stricto. We were unable to assign either a holotype for L. cinerea (Born, 1778) or a fi gured specimen of L. versicolor (Gmelin, 1791) to genetic lineages with any statistical confi dence, although the shell outline of the former is most similar to L. aff. cinerea cIWP and the latter to L. aff. cinerea SW Pacifi c. Finally, using morphometrics, in combination with other shell characters, two fossil species, one from the cinerea group from the Pleistocene and one Japanese species from the Eocene, were compared with extant species. Using this method in combination with other characters, we suggest that the Japanese L. kurodai Itoigawa, 1955 is most likely a member of the coronata group and the Pleistocene cinerea fossil is most similar to L. cinerea cIWP.

Phylogeography and Genetic Differentiation among Populations of the Moon Turban Snail Lunella granulata Gmelin, 1791 (Gastropoda: Turbinidae)

“…The moon turban snail ( Lunella granulata Gmelin, 1791), distributed primarily in the Indo-West Pacific area and ranging from Japan and Korea to China, preferentially inhabits rocky shores in the intertidal zone [3–5]. From an economic perspective, L. granulata is one of the most important species for the residents of the Penghu Archipelago and Taiwan due to its abundance and widespread distribution.…”

Elliptic Fourier analysis of leaf shape in southern AfricanStrychnossectionDensiflorae(Loganiaceae)

“…Combining these data with genetics, they unravel the origin and domestication history of ancient European cultivars of grapevine ( Vitis vinifera L.). Other authors have found the technique useful for uncovering cryptic diversity and for quantifying allometry (Langlade et al ., ; Feng et al ., ; Williams, Hall & Kuklinski, ).…”

Phenotypic divergence in viviparid snails in a recently converted freshwater lagoon

“…Elliptic Fourier analysis was used to describe and quantify shell morphology (Williams et al 2012, Doyle et al 2018, Jackson & Claybourn 2018. Images of S. quadrata shells were acquired using a digital camera (K-S2, Ricoh, Japan), from which elliptic Fourier analysis was performed using SHAPE (Iwata & Ukai 2006).…”