Tag Archives: westindies

Urocoptidae revisited

Uit de Weerd et al. (2016) have published a paper on the evolutionary history of biogeography of the land snail family Urocoptidae. It is a sequel following previous papers of Uit de Weerd dealing with the Caribbean region.

The authors reconstructed the phylogeny of Urocoptidae based on multi-locus (partial 28S, H3 and COI sequences) analyses (MrBayes, BEAST, GARLI) of 65 species, representing 44 recognized genera. Biogeographical analyses of a subset of the time-calibrated BEAST trees were made both with (DEC and DEC+J analysis in BioGeoBEARS) and without (S-DIVA in RASP) palaeo-geographical assumptions. In the DEC and DEC+J analyses we examined the effect of different settings for dispersal between directly connected areas relative to that between areas without direct land connection. Urocoptidae has been present on the Greater Antilles Arc from at least Middle Eocene onwards. Morphologically diverse and previously unrecognized clades evolved on most Caribbean (palaeo)islands. Jamaica was colonized at least twice. Dispersal multiplier matrices with moderately constrained dispersal between areas without direct land connections describe the phylogeographical history of the family with higher DEC and DEC+J lnL scores than uniform matrices. Urocoptids constitute an old element of the Greater Antillean biota, predating a proposed GAARlandia landspan connection to South America. The biogeographical history and evolution of Urocoptidae were shaped primarily by the geographical distribution of Caribbean landmasses, in combination with occasional oversea dispersal. Oversea dispersal allowed colonization of palaeogeographically isolated areas, such as Jamaica and present-day western Cuba, where presumably the absence of ecological competitors led to independent radiations into similar shell types. A follow-up paper will be dealing with the taxonomic consequences of this study.

Uitdeweerd16

With the representation of 44 genera out of the total 65 recognized genera within the family, this is a comprehensive molecular analysis. No other Caribbean family has been treated this way, thus this study provides unique insights and helps to test competing biogeographical theories about land snail distribution in this region.

Reference:
Uit de Weerd, D.R., Robinson, D.G. & Rosenberg, G., 2016. Evolutionary and biogeographical history of the land snail family Urocoptidae (Gastropoda: Pulmonata) across the Caribbean region. – Journal of Biogeography (early online access) http://wileyonlinelibrary.com/journal/jbi | doi:10.1111/jbi.12692

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Photo of the day (163): Polydontes

These are some additional photos by Rolf Nijsse, kindly transmitted by Herman Cremers, taken during a recent trip to Puerto Rico, Luquillo Experimental Forest. They show Polydontes acutangula (Burrow, 1815), which is very similar to the species shown here but may be distinguished by its dark rim of the foot. N.B.: A recent preliminary report on the terrestrial snails of the island by Robinson & Field mentions this species as Parthena acutangula.

P1130654

P1130661

The classification of this group of snails (currently in Pleurodontidae) is to a large extent based on anatomical differences (see Wurtz, 1955).

The Luquillo Experimental Forest is a field station for ecological work, and snails have been the subject already for decades. A review may be found here.

Reference:
Wurtz, C.B. (1955). The American Camaenidae (Mollusca: Pulmonata). – Proceedings of the Natural Sciences of Philadelphia 107: 99-143. [http://www.jstor.org/stable/4064483]

Photo of the day (162): Drymaeus

On Curaçao, Drymaeus virgulatus (Férussac, 1821) is occurring in a selected number of areas. One of these is the Christoffelpark. These snails are usually found as clusters on the stem of trees, in this case along a ‘rooi’ in the Zorgvlied section of this nature protection park.

01 Track Zorgvlied - Roi NE Seru Pretu 150122 K93

 

Drymaeus

Thanks to François van der Hoeven and his members of the Workgroup Archeologie, for their interesting weekly trips over the island, and the well-illustrated reports on them.

 

 

 

 

Reviews of Annulariidae

G. Thomas Watters recently had two papers out on Annulariidae. The first one (2014a) is a “preliminary review” of the Lesser Antillean species. The brief abstract reads “The Annulariidae of the Lesser Antilles, including the Virgin Islands, Isla de Vieques, and Isla Culebra, are reviewed. Eleven species are recognized in three genera. With rare exceptions, all occur in the Limestone Caribbees. One species, Parachondria basicarinatus (Pfeiffer, 1855), from St. Croix, may be extinct. All are believed to be related to Puerto Rican taxa.”

The following species are recognised: Chondropoma (Chondropoma) julieni Pfeiffer, 1866; Chondropoma (Chondropoma) pupiforme (Sowerby, 1843); Chondropoma (Chondropoma) rufilabre (Potiez & Michaud, 1838); Parachondria (Parachondria) basicarinatus (Pfeiffer, 1855); Parachondria (Parachondria) lineolatus (Lamarck, 1822); Parachondria (Parachondria) santacruzensis (Pfeiffer, 1855); Diplopoma (Diplopoma) crenulatum (Potiez & Michaud, 1838); Diplopoma (Diplopoma) decussatum (Lamarck, 1822); Diplopoma (Diplopoma) sulculosum (Pfeiffer, 1852).

Watter2014a

The second paper (2014b) presents a revision of the Central American taxa of the family. “Twenty annulariid taxa are reviewed from Central America, including three new species and one new genus. One species is regarded as an incertae sedis and two as mislabeled lots of Cuban origin. Many species are highly endemic. Although not speciose, Central America has a high diversity of conchological forms and may represent the ancestral source of annulariids
in general.” A key to the genera is also presented.

The following taxa are recognised c.q. described: Choanopomops largillierti (Pfeiffer, 1846); Halotudora gaigei (Bequaert & Clench, 1931); Halotudora gruneri (Pfeiffer, 1846); Halotudora kuesteri (Pfeiffer, 1852); Gouldipoma chiapasense (Crosse & Fischer, 1877); Gouldipoma sumichrasti (Crosse & Fischer, 1874); Gouldipoma coltrorum new species; Gouldipoma terecostatum (Thompson, 1966); Gouldipoma callipeplum (Solem, 1961); Gouldipoma chrysostiria new species; Gouldipoma thomasi (Solem, 1961); Gouldipoma trochleare (Pfeiffer, 1852); Tudorisca andrewsae (Ancey, 1886); Paradoxipoma new genus; Paradoxipoma enigmaticum new species; Diplopoma osberti (Tristram, 1861); Diplopoma rigidulum (Morelet, 1851); Parachondria cordovanus (Pfeiffer, 1857); Parachondria cordovanus (Pfeiffer, 1857); “Choanopoma” cygni Pilsbry, 1930.

Watters2014b

For all of these taxa data are given about type material, synonymy, material seen and distribution, habitat and conservation status, (re-)description, variation, comparison with other taxa, original description (translated), etymology.

These two very thorough papers are new hallmarks for this group of snails.

References:

Watters, G.T., 2014a. A preliminary review of the Annalariidae (Gastropoda: Littorinoidea) of the Lesser Antilles. – The Nautilus 128: 65–90.
Watters, G.T., 2014b. A revision of the Annulariidae of Central America (Gastropoda: Littorinoidea). – Zootaxa 3878: 301–350.

 

Cerion ABC

One of my first sights of Neotropical land snails were very large bottles full of Cerion shells from Curaçao in the lab of the late P. Wagenaar Hummelinck. Willy de Vries, who worked at the same period in the lab, studied these shells from Aruba, Bonaire and Curaçao (in Dutch ‘ABC islands’) by taking various measurements on hundreds of shells. I recall her to be disappointed to conclude that “no obvious geographic variation in Cerion uva exists” (de Vries, 1974). This contrary to H.B. Baker, who had described various subspecies from the islands, and had concluded that Curaçao has western, central and eastern faunal regions (Baker, 1924). Wagenaar Hummelinck (1990), however, rejected this hypothesis and concurred with Gould’s (1969) partition of Curaçao in a western and eastern region.

Harasewych2014_f2

Harasewych has now published a nice paper restudying the Cerions from these islands using molecular data (Harasewych, 2014). The abstract reads: “The systematic relationships of the Cerion uva complex and its constituent taxa are reviewed based on partial sequences of the cytochrome c oxidase I and 16S rDNA genes from 19 populations spanning the geographic range of the species complex and including the type localities of 8 of the 9 subspecies and forms. Molecular data support the conclusion of prior morphometric studies that all living Cerion inhabiting Aruba, Curaçao and Bonaire are members of a single species, C. uva. Sequence variability among and within populations is not sufficiently discontinuous to segregate populations into discrete, specieslevel taxa. Three of four subspecies, proposed on the basis of geographic isolation during the Quaternary, C. uva uva (Linnaeus, 1758), the nominotypical subspecies from eastern Curaçao, C. uva knipensis Baker, 1924, from western Curaçao, and C. uva bonairensis Baker, 1924, from Bonaire, are all supported by distinctive haplotypes. Cerion uva arubanum Baker, 1924, a taxon based on living specimens from Aruba, is shown to be a synonym of C. uva uva, with which it shares a preponderance of haplotypes. It is conjectured that C. uva was widespread on Aruba during the Quaternary, but had become extinct on that island, and was reintroduced from a population near Willemstad in eastern Curaçao by humans (either by Caquetío Indians or by European settlers) within the past 800 years. Further investigation is needed to determine if Quaternary Aruban Cerion warrant subspecific recognition. On the island of Curaçao, molecular data lend support to the partition of the Cerion fauna into C. uva knipensis, which is confined to an isolated western region, as defined by Baker, and C. uva uva, which inhabits a broad, eastern region that is composed of Baker’s central and eastern regions. A population at Ronde Klip in eastern Curaçao has remained genetically isolated, and retains subspecific status as C. uva diablensis Baker, 1924. A neotype is designated for Turbo uva Linnaeus, 1758, as is necessary to provide an objective standard of reference for this species-group taxon, and for the genus- and family-level taxa based upon it.”

Harasewych2014_f7

References:

Baker, H.B., 1924. Land and freshwater molluscs of the Dutch
Leeward Islands. – Occasional papers of the Museum of Zoology.
University of Michigan 152: 1–160.
Gould, S.J., 1969. Character variation in two land snails from the
Dutch Leeward Islands: geography, environment, and evolution. –
Systematic Zoology 18: 185–200.
Harasewych, M.G., 2014. Systematics and phylogeography of Cerion sensu stricto (Pulmonata: Cerionidae) from Aruba, Curac¸ao and Bonaire. – Journal of Molluscan Studies (Advance Access): 1–19.
Vries, W. de, 1974. Caribbean land molluscs: notes on Cerionidae. –
Studies on the Fauna of Curac¸ao and other Caribbean Islands 45: 81–117
Wagenaar Hummelinck, P., 1990. About the malacological
subdivision of Curac¸ao; a review. – Contributions to Zoology 60: 181–187.