Crocidura brevicauda, Esselstyn & Achmadi & Handika & Swanson & Giarla & Rowe, 2021

Esselstyn, Jacob A., Achmadi, Anang S., Handika, Heru, Swanson, Mark T., Giarla, Thomas C. & Rowe, Kevin C., 2021, Fourteen New, Endemic Species Of Shrew (Genus Crocidura) From Sulawesi Reveal A Spectacular Island Radiation, Bulletin of the American Museum of Natural History 2021 (454), pp. 1-109 : 67-69

Crocidura brevicauda , new species

LSID: urn:lsid:zoobank.org:act:62AA5599-D510-4AAB-B516-1D901C972A6E

HOLOTYPE: MZB 43009 (= MVZ 237632 ), an adult female collected on 12 August 2016 by H. Handika, and prepared as a cleaned skull, forma-

lin-fixed carcass, and tissue samples. External measurements of the holotype are 130 mm × 56 mm × 15 mm × 9 mm = 12.0 g. The voucher specimen and a tissue sample will be permanently curated at MZB and an additional tissue will be retained at MVZ.

TYPE LOCALITY: Indonesia, South Sulawesi Province, Luwu Regency, Latimojong District, Ulusalu , Gamaru Village , Mt. Latimojong ; 3.43103° S, 120.09457° E, 2518 m elevation.

ETYMOLOGY: Brevicauda is Latin for “short tail,” indicating the relatively stubby tail that this species possesses.

GEOGRAPHIC DISTRIBUTION: Only known from Mt. Latimojong of the west-central area of endemism ( fig. 1 ), between 2300 and 2500 m elevation ( fig. 13 ). The surveys we conducted on Mt. Latimojong during 2011 between 2000 and 2300 m did not find this species ( table 3 ).

DIAGNOSIS: Crocidura brevicauda is a fairly large shrew ( tables 2 , 12 ) with a stocky build ( fig. 17 ) and relatively short tail ( fig. 9 ). The tail is somewhat thick and dark brown with many applied hairs. It has sparse, but long bristles along nearly its entire length ( fig. 33A ). The long dorsal fur (7–8 mm at middorsum) is gray-brown to dark brown, with a gray base and short brown tip. The fur coat is sufficiently thick and long that it somewhat obscures the ears. The hind feet are darker than the forefeet, the former being brown to dark brown dorsally, while the latter are pale brown. On all four feet, the thenar and hypothenar are less prominent than the four interdigital pads ( fig. 33A ). The skull width relative to length is midsized at the braincase and interorbital region ( figs. 10 , 34A ). The rostrum is long relative to skull length ( fig. 10 ). The lambdoidal ridge is prominent and the lateral margins of the braincase are somewhat angular, forming a dull point at the squamosal-parietal suture ( fig. 34A ).

COMPARISONS: Crocidura brevicauda is considerably larger than all members of the Small-Bodied Group, larger than C. australis and C. pallida of the Rhoditis Group, has a much shorter tail than members of the Long-Tailed Group, is slightly smaller and has a narrower braincase than C. rhoditis and C. pseudorhoditis of the Rhoditis Group, is darker in color (pelage and feet) than all members of the Rhoditis Group, and is larger than all members of the Ordinary Group (detailed below) except C. nigripes . Crocidura nigripes , however, is usually very darkly colored, particularly on its feet, whereas C. brevicauda has pale brown to dark brown feet ( fig. 33 ). Crocidura brevicauda also has a somewhat stockier body ( fig. 17 ), much wider interorbital region ( fig. 10 ), more rounded braincase, and a less robust dentition ( fig. 34A ) than C. nigripes . Crocidura brevicauda has a more luxuriant pelage than all other species except C. musseri and C. caudicrassa , the other member of the Thick-Tailed Group. Crocidura caudicrassa is generally similar to C. brevicauda , but can be distinguished by its even thicker fur, heavier body ( fig. 17 ), longer skull, wider rostrum and braincase, and thicker tail ( table 12 ).

COMMENTS: The extent of montane habitats on Mt. Latimojong is fairly limited and isolated from other such areas ( fig. 1 ). As such, the geographic range of Crocidura brevicauda may be quite small. See the next account for details of phylogenetic relationships and coalescent species delimitation results.

SPECIMENS EXAMINED: Mt. Latimojong ( MVZ 237568 , 237597 , 237616 , 237629–237631 , 237633 ; MZB 43009 ).

Figures

FIG. 1. Maps of A, Southeast Asia and B, Sulawesi showing topographical relief and the approximate boundaries (thick black lines) between areas of endemism (sensu Evans et al., 2003). Two-letter abbreviations in dark gray typeface identify the north-east (NE), north-central (NC), north-west (NW), west-central (WC), eastcentral (EC), south-west (SW), and south-east (SE) areas of endemism. Diamonds label localities where we, or others, have collected shrew specimens since 2010 with the mountain (or locality) name. Stars indicate type localities (Temboan and Pinedapa) from Miller and Hollister (1921). The type localities for the only two Crocidura described from the island since 1921 are Mt. Rorekatimbo (west-central area of endemism) for C. musseri Ruedi (1995) and Mt. Dako (north-west area of endemism) for C. caudipilosa Esselstyn et al. (2019).

FIG. 13. Elevational records of all species of Crocidura known from Sulawesi. Each point represents a specimen. For specimens associated with a minimum and maximum elevation, we used the center of the given elevational range. Sample sizes are given above the x-axis. Species are grouped according to the species groups used in the text (Thick = Thick-Tailed Group).

FIG. 17. Box plots showing the length of the hind foot (HF) relative to the head-and-body length (HBL) and the ratio of mass to HBL. Plots show the median, 1st and 3rd quartiles, the maximum value within 1.5 × interquartile range (distance between 1st and 3rd quartiles; IQR), the minimum value within 1.5 × IQR, and outliers (black circles). Sample sizes are shown along the x-axis. Species are ordered along the x-axis according to the species groups used in the text (Thick = Thick-Tailed Group). Lengths are in mm and mass is in grams.

FIG. 9. Box plots showing variation in external measurements from all species of Sulawesi shrew. Plots show the median, 1st and 3rd quartiles, the maximum value within 1.5 × interquartile range (distance between 1st and 3rd quartiles; IQR), the minimum value within 1.5 × IQR, and outliers (black circles). Sample sizes are shown along the x-axis. Species are grouped according to the species groups used in the text (Thick = Thick- Tailed Group). All measurements in mm. HBL = head-and-body length.

FIG. 33. Images showing the ventral surface of the hind foot and dorsal surfaces of the tail base (approximately 1 cm from rump) and tail tip from the two members of the Thick-Tailed Group: A, Crocidura brevicauda, MVZ 237632 (left hind foot); and B, C. caudicrassa, MZB 34795 (right hind foot). In B the upper scale bar applies to the foot and the lower to the tail.

FIG. 10. Box plots of relative skull measures showing braincase breadth (BB), interorbital width (IOW), and rostral length (RL) divided by condyloincisive length (CIL) and BB divided by IOW for all species of Sulawesi shrew. Plots show the median, 1st and 3rd quartiles, the maximum value within 1.5 × interquartile range (distance between 1st and 3rd quartiles; IQR), the minimum value within 1.5 × IQR, and outliers (black circles). Sample sizes are shown along the x-axis. Species are ordered according to the species groups used in the text (Thick = Thick-Tailed Group).

FIG. 34. Images showing dorsal, ventral, and lateral views of the skull and lateral and occlusal views of the dentary of the two members of the Thick-Tailed Group: A, Crocidura brevicauda, MVZ 237632; and B, C. caudicrassa, MZB 34795.