The Bornean representatives of the genus Georissa (Hydrocenidae) have small, dextral, conical, calcareous shells consisting of ca. three teleoconch whorls. Our recent study on the Georissa of Malaysian Borneo has revealed high intra- and inter-specific variation in the "scaly" group (a group of species with striking scale-like surface sculpture). The present study on the "non-scaly" Georissa is the continuation of the species revision for the genus. The "non-scaly" species are also diverse in shell sculptures. This informal group comprises Georissa with subtle spiral and/or radial sculpture. The combination of detailed conchological assessment and molecular analyses provides clear distinctions for each of the species. Conchological, molecular, and biogeographic details are presented for 16 species of "non-scaly" Georissa. Three of these are new to science, namely Georissacorrugatasp. n., Georissainsulaesp. n., and Georissatrusmadisp. n.
The Bornean hydrocenids have so far been understudied compared to other non-pulmonate snails in this region. In the present study, we review a first group of minute land snail species belonging to the genus Georissa (Gastropoda, Hydrocenidae) from Malaysian Borneo. This group is restricted to the species with conspicuous scale-like sculpture on the shell. Based on materials from recent fieldwork, museums, and personal collections, Malaysian Borneo hydrocenids are more complex and diverse in shell characters than previously anticipated. Here, a molecular, conchological, and biogeographic study of this "scaly group" is presented. We recognise 13 species of which six are new to science, namely Georissa anyiensissp. n., Georissa muluensissp. n., Georissa bauensissp. n., Georissa silaburensissp. n., Georissa kinabatanganensissp. n., and Georissa sepulutensissp. n.
A comparative leaf micromorphological study of Melastoma malabathricum, M. malabathricum var. alba and M.
sanguineum (Melastomataceae) was carried out by scanning electron microscope. Characters such as epidermal cell
shape, trichomes and stomatal type and distribution were observed. Non-glandular trichomes are present in all species
examined. The stomata are all of paracytic type and dispersed randomly over the whole abaxial surface. The patterns of
surface sculpturing and outer stomatal rim are unique in all the species examined. Leaf micromorphology has significant
taxonomic value in the genus Melastoma and the present study has added some new taxonomic information for the genus
Melastoma.
Crassignatha Wunderlich, 1995 is redefined to include species with six eyes in three diads, chelicerae fused only near the base, sculpturing on the carapace, one or two clasping spurs on tibia II, a bilateral scutum of the male abdomen, and globular spermathecae and adjacent copulatory openings in the female. A key and distribution map are provided for 24 Crassignatha species in this paper. Diagnoses and illustrated photographs are provided for 22 species from China, Malaysia, Thailand, and Vietnam. Thirteen species are described and documented as new to science: C. baihua Y. Lin & S. Li, sp. nov. (♂♀), C. bangbie Y. Lin & S. Li, sp. nov. (♀), C. changyan Y. Lin & S. Li, sp. nov. (♀), C. dongnai Y. Lin & S. Li, sp. nov. (♀), C. gucheng Y. Lin & S. Li, sp. nov. (♂♀), C. mengla Y. Lin & S. Li, sp. nov. (♂♀), C. nantou Y. Lin & S. Li, sp. nov. (♂♀), C. nasalis Y. Lin & S. Li, sp. nov. (♂♀), C. rostriformis Y. Lin & S. Li, sp. nov. (♂♀), C. shunani Y. Lin & S. Li, sp. nov. (♂♀), C. si Y. Lin & S. Li, sp. nov. (♂♀), C. thamphra Y. Lin & S. Li, sp. nov. (♀), and C. xichou Y. Lin & S. Li, sp. nov. (♀). Three new combinations are proposed: C. bicorniventris (Lin & Li, 2009), comb. nov., C. quadriventris (Lin & Li, 2009), comb. nov., and C. shiluensis (Lin & Li, 2009), comb. nov. are transferred from Patu Marples, 1951. DNA barcodes and genetic distances of seventeen species are obtained to confirm correct identification. Types of seven known Chinese Crassignatha species are re-examined, and the taxonomic placement of C. longtou Miller, Griswold & Yin, 2009 may be incorrect based on morphological and molecular data.