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Abstract We describe 3 new species of shrews (Eulipotyphla, Soricidae, Crocidura) from West Sumatra, Indonesia. Two of these taxa were found above 1,800 m on Mt. Singgalang. The third taxon was found above 1,660 m on Mt. Talamau, 65 km northwest of Mt. Singgalang. We also resurrect Crocidura aequicauda based on 2 specimens from Mts. Tujuh and Kerinci, which lie near the border between West Sumatra and Jambi provinces. Several methodological approaches support our findings: linear cranial morphometrics, landmark-based 2D geometric morphometrics, and molecular phylogenetics using both mtDNA and 6 nuclear exons. A multilocus species-tree analysis places the 3 new species and C. aequicauda in a clade with the Javan endemics C. monticola and C. umbra. Although the 2 taxa from Mt. Singgalang are recovered as sister species, 1 is nearly twice the size of the other, and they are divergent in several other morphological characters, such as tail length, cranium size, and pelage color and texture. Recently diverged yet morphologically disparate sister taxa living syntopically in an isolated habitat “island,” like the montane forests of Mt. Singgalang, is unusual in mammals but documented in other Crocidura on neighboring Java and Borneo; these 2 new taxa represent the first known case of this phenomenon on Sumatra. Our results bring the number of Sumatran Crocidura to 10, 9 of which are endemic to the island. All 3 of the new species appear to be endemic to a single mountain and were not detected in similar surveys of nearby mountains. If this local endemism pattern is common, it would indicate that Sumatra’s mammal diversity may be severely underestimated, largely due to the paucity of small-mammal surveys and museum specimens.
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A new species of Rigiolepis (Ericaceae: Vaccinioideae) from the Gayo Plateau, Aceh Province, Indonesia
A new species of Ericaceae from the Gayo Plateau, Aceh Province, Indonesia is described. Rigiolepis gayoensis resembles R. lanceolata but differs by having shorter leaves, non-protruding basal leaf glands, longer flowering pedicels, a glabrous hypanthium, and a dark red or maroon corolla. A detailed morphological description, ecological notes, conservation status, and photographs are presented. The new species represents the third species of Rigiolepis found in the island of Sumatra. A key to the species of Rigiolepis in Sumatra is provided.
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- PAR ID:
- 10533643
- Publisher / Repository:
- Webbia
- Date Published:
- Journal Name:
- Webbia
- Volume:
- 78
- Issue:
- 2
- ISSN:
- 2169-4060
- Page Range / eLocation ID:
- 73 to 78
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.36253/jopt-14872
