Chodsigoa dabieshanensis sp. nov.
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publication ID |
https://dx.doi.org/10.3897/zookeys.1083.78233 |
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publication LSID |
lsid:zoobank.org:pub:0BB575E8-AF6A-4FEB-A41A-D3FFD27B01FC |
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persistent identifier |
https://treatment.plazi.org/id/AFACD42E-DC6C-5657-8612-A6C37DF62B8B |
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treatment provided by |
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scientific name |
Chodsigoa dabieshanensis sp. nov. |
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Chodsigoa dabieshanensis sp. nov.
Figures 4 View Figure 4 , 5 View Figure 5
Suggested common name.
Dabieshan long-tailed shrew; 大别山缺齿鼩 (Dabieshan Quechiqu)
Holotype. AHU2008FZL005, an adult female collected by Zhen Xu and Ruolei Sun in August 2020, at Foziling natural reserve (31°07'07"N, 116°14'41"E, 1187 m a.s.l.), the north slope of the Dabie Mountains, Huoshan County, Luan City, Anhui province, China. Cleaned skulls and remaining carcasses frozen at -20 °C deposited in the Biological Museum of Anhui University (BMAHU).
Paratypes. AHUDBS017001-005; AHU2008FZL001-004, 006. Ten specimens collected between May 2017 and August 2020 from the Dabie Mountains, Anhui province, China. All specimens are deposited in the Biological Museum of Anhui University (BMAHU).
Etymology.
The specific name Chodsigoa dabieshanensis is derived from the Dabie Mountains, the type locality of the new species: - shan means mountain in Chinese, and the Latin adjectival suffix - ensis means "belonging to".
Diagnosis.
The new species is assigned to the genus Chodsigoa for having three upper unicuspid teeth, with the tips of the teeth lightly pigmented (Fig. 4 View Figure 4 ). Chodsigoa dabieshanensis sp. nov. can be distinguished from the other known species of Chodsigoa by the following combination of characters: small to medium in size (HB = 67.22 mm; CIL = 19.08 mm), dark brownish pelage; tail shorter than the HB, nearly similar ventral and dorsal pelage color, a small tuft of longer hairs at the tip of the tail (Fig. 5 View Figure 5 ); markedly flattened braincase; and the foramen magnum is relatively wider than C. hypsibia . Phylogenetic analyses show that the new species is monotypic, sister to C. hypsibia and C. parva (Fig. 3 View Figure 3 ).
Description.
A small to medium-sized shrew (W = 5.24 ± 0.36 g, range 4.67-5.89 g; HB = 67.22 ± 3.23 mm, range 62.00-73.00 mm, Table 2 View Table 2 ) with dark brown dorsal pelage and slightly paler ventral pelage (Fig. 5 View Figure 5 ). Tail is short (TL = 59.67 ± 3.28 mm), about 90% of the head and body length, brown above, slightly paler below, and with a small tuft of longer hairs at the tip. External ears are prominent, rounded, and covered with very short dark hairs. Eyes are very small. The dorsal surfaces of hands and hind feet are covered with short brown hair, lighter at the margin. The thenar and hypothenar pads at the soles of the hindfeet are well separated.
The skull of C. dabieshanensis sp. nov. is short and broad, and the braincase is markedly flattened (Fig. 4 View Figure 4 ). The skull is similar to C. hypsibia , but much shorter and broader. The rostrum is short, and the interorbital region is wide. From the ventral view, the rostrum gradually narrows in the premaxillary region. The palate is short, with an abrupt posterior edge. The basisoccipital is developed and the ridges are approximately parallel. The dentition is the same for the genus: 3.1.1.3/2.0.1.3 = 28. The first incisor is long, falciform; the apex straight downwards; the talon much lower than U1, approximately equal to U3. Three upper unicuspids are present. All unicuspids are crowded and overlap slightly at the base. U1-U3 gradually decrease in size; U3 is about half as high as U1, and in contact with P4, which is large and triangular in outline. The posterior borders of P4 and M1 are deeply excavated, appearing crescent, while the posterior borders of M2 are much shallower. M3 is reduced and much narrower with a single lobe. The tips of the anterior teeth have a lightly pigmented chestnut color except the molars.
The mandible is slender. The coronoid process is tall and squared, rising straight upward from the posterior of the toothrow. The condyloid process is weak and bi-faceted, forming an angle at approximately 45° with the coronoid process. The angular process is long, straight, and very thin. The first lower incisor is long, with only a single basal cusplet. The incisor is slightly curved upwards, forming a hook at the tip. The first lower unicuspid is small and procumbent, crowded with a large incisor and the following premolar. The premolar has one forward-leaning cusp. The molar gradually decreases in size from M1 to M3. Only the tips of I1, U1, P1, and M1 are chestnut-pigmented but not those of M2 and M3.
Comparison.
Among the species in the genus Chodsigoa , C. dabieshanensis sp. nov. is morphologically similar to the widely distributed C. hypsibia . However, the new species can be distinguished from C. hypsibia by many characters. In terms of body size, C. dabieshanensis sp. nov. is much smaller than C. hypsibia for most external and craniomandibular measurements (Table 2 View Table 2 ). In particular, the range of weight (4.67-5.89 g vs 6.40-14.00 g) and rostral length (6.48-6.81 mm vs 6.93-9.00 mm) between the two species does not overlap. The overall pelage of C. dabieshanensis sp. nov. is dark brown, almost black, which differs from the gray pelage of C. hypsibia. The skull of C. dabieshanensis sp. nov. is relatively shorter and broader than C. hypsibia , especially in the interorbital region, which appears much flatter (Fig. 4 View Figure 4 ). The foramen magnum breadth is relatively larger than C. hypsibia. The posterior borders of M2 in C. hypsibia are much more deeply excavated than in C. dabieshanensis sp. nov.. In C. dabieshanensis sp. nov., the basioccipital is well developed and the ridges are approximately parallel. By contrast, the basioccipital of C. hypsibia is narrow, so the ridges are nearly confluent in the middle.
Chodsigoa dabieshanensis sp. nov. (CIL = 19.08 ± 0.22 mm) can be easily distinguished from C. parva (CIL = 15.79 ± 0.27 mm) by its much larger size and the ranges of most of their external and cranial measurements do not overlap (Table 2 View Table 2 ). Furthermore, the tail of C. dabieshanensis sp. nov. (TL/HB = 80%) is relatively longer than C. parva (TL/HB = 88%). If the mean condyloincisive length is used as an indicator of overall size, C. dabieshanensis sp. nov. (CIL = 19.08 ± 0.22 mm) is larger than C. sodalis (CIL = 17.97 ± 0.12 mm), but smaller than C. furva (CIL = 20.63 ± 0.39 mm), C. parca (CIL = 20.37 ± 0.29 mm), and C. smithii (CIL = 22.23 ± 0.54 mm) (Table 2 View Table 2 ). The markedly flattened cranium of C. dabieshanensis sp. nov. is clearly distinguished from all other species in the genus, including C. caovansunga , C. furva , C. hoffmanni , C. parca , C. salenskii , C. smithii , and C. sodalis. The tail of C. dabieshanensis sp. nov. is shorter than head and body length, and it differs from C. sodalis (TL/HB ≈ 100%) and all other Chodsigoa species (TL/HB> 100%). The new species has a tuft of longer hair at the tip of the tail, in contrast to C. caovansunga , C. furva , and C. smithii . The thenar and hypothenar pads at the soles of the hindfeet are well separated and distinguishable from C. caovansunga , whose thenar and hypothenar pads of hindfeet are close together.
Distribution and habits.
Chodsigoa dabieshanensis sp. nov. is currently known from Yaoleping National Nature Reserve, Bancang Natural Reserve, and Foziling Natural Reserve, all located in the Dabie Mountains, Anhui province, eastern China. Most specimens were collected from deciduous broad-leaf forests at 750-1250 m a.s.l.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.