NEW SOUTHERNMOST RECORDS OF THE GENUS PUPISOMA (VALLONIDAE) USING A NOVEL COLLECTING METHOD ON TREE BROMELIADS

ANDRÉS OSVALDO PORTA; SERGIO S. MIQUEL

JOURNAL OF CONCHOLOGY

CONCHOLOG SOC GR BRIT IRELAND COURTAULD INST BIOCHEMISTRY

Lugar: Dublin; Año: 2021

0022-0019

Arboreal micromolluscs are underrepresented in natural collections probably because of the intrinsic difficulties involving their observation and collection in natural environments. Micromolluscs of the genus Pupisoma Stoliczka, 1873 (Vallonidae) usually live on the bark and leaves of trees and other plants and are distributed in tropical and subtropical regions of both hemispheres, except in arid regions and oceanic islands1. Four species have been recorded in Argentina with records in tropical and temperate areas of the country (Fig. 1A, yellow circles) 2?5: 1) P. (Ptychopatula) dioscoricola (C. B. Adams, 1845) recorded from El Zapallar and Resistencia (Chaco Province); Lumbrera (Salta Province) and San Miguel de Tucumán (Tucumán Province), as well from various localities in southern Brazil6?,8; 2) P. latens Hylton Scott, 1960 from Cabana and Mina Clavero (Córdoba Province); San Miguel de Tucumán; Cerro San Javier and Horco Molle (Tucumán Province); 3) P. puella Hylton Scott, 1960 from Iguazú (Misiones Province); and 4) P. macneilli (Clapp, 1918), from Cerro San Javier (Tucumán Province) by Hausdorf4 in his revision of South American species of the genus. In the same paper that author synonymized P. puella and P. latens with P. dioscoricola and P. comicolense, respectively on the basis of conchological characters. An unidentified species of the genus has been recorded in various localities in the Misiones Province9. Here we present new records of the genus that extend the southern distribution of the genus Pupisoma by ~500km obtained using a method that, as far as we know, has not been previously utilised to collect micromolluscs on trees10. The molluscs were collected as part of an ongoing survey of the arachnid fauna associated with the bromeliads Tillandsia aëranthos (Loisel) L.B. Sm. and T. recurvata (L.) L. in Buenos Aires City and Buenos Aires Province, Argentina. Collecting methodologyMicromolluscs were extracted from bromeliads with a shake and wash technique originally developed by Zacharda et al.11 for collectingeriophyid and phytoseid mites on plants12. In our version of this technique, epiphyte bromeliads were collected in several trees. In the laboratory, they were immersed in 70?90% ethanol in a covered beaker and gently shaken several times. After resting for several hours to allow the precipitation of the invertebrate associated fauna, the plant material was carefully removed with forceps and the alcohol containing the preserved material was transferred to a Petri dish and studied under a dissecting microscope. All the collected molluscs belong to the genus Pupisoma and were deposited in the Invertebrates Division of the Museo Argentino de Ciencias Naturales ?Bernardino Rivadavia? (MACN-In). Shells and radulae were sputter coated with gold-palladium and examined using a Phillips XL Series 30 scanning electron microscope