Choeroniscus minor (Peters, 1868)

Velazco, Paúl M., Voss, Robert S., Fleck, David W. & Simmons, Nancy B., 2021, Mammalian Diversity And Matses Ethnomammalogy In Amazonian Peru Part 4: Bats, Bulletin of the American Museum of Natural History 2021 (451), pp. 1-201 : 42-43

Choeroniscus minor (Peters, 1868)

Figure 10B

VOUCHER MATERIAL (TOTAL = 9): Jenaro Herrera (MUSM 862, 5586), Nuevo San Juan (AMNH 273066, 273106; MUSM 13195, 15171– 15173), Quebrada Lobo (MUSA 15127); see table 21 for measurements.

UNVOUCHERED OBSERVATIONS: None.

IDENTIFICATION: Before the revision by Simmons and Voss (1998), specimens of Choeroniscus minor were referred to several species ( C. inca , C. minor , and C. intermedius ) that were diagnosed primarily by the length of the rostrum (Koopman, 1978). After reviewing specimens (including holotypes) throughout the distribution of these nominal taxa, Simmons and Voss (1998) concluded that they represent a single species for which C. minor (Peters, 1868) is the oldest available name. Choeroniscus minor is distinguished from other congeners by the following combination of characteristics: rostrum shorter than braincase, posterolateral margin of palate unnotched, pterygoids moderately inflated, forearm ≤ 38 mm, greatest length of skull> 21 mm, and maxillary toothrow>7.5 mm (Simmons and Voss, 1998; Griffiths and Gardner, 2008a; Solmsen and Schliemann, 2008). This species exhibits marked sexual size dimorphism, with females being larger than males (Husson, 1962; Brosset and Charles-Dominique, 1990; Simmons and Voss, 1998; Solmsen, 1998; Solmsen and Schliemann, 2008). Additional descriptions and measurements of C. minor have been provided by Goodwin and Greenhall (1961), Husson (1962), Swanepoel and Genoways (1979), Brosset and Charles-Dominique (1990), Lim et al. (2005), and Solmsen and Schliemann (2008). No subspecies are currently recognized (Simmons and Voss, 1998; Griffiths and Gardner, 2008a; Solmsen and Schliemann, 2008).

The Jenaro Herrera specimens were originally identified as Choeroniscus intermedius by Ascorra et al. (1993), but Fleck et al. (2002) and Medina et al. (2015) correctly identified their specimens from Nuevo San Juan and Quebrada Lobo, respectively, as C. minor . The voucher material we examined from the Yavarí-Ucayali interfluve conforms to previous descriptions of C. minor , with measurements that fall within the range of size variation now documented for the species. However, it is noteworthy that one specimen (MUSM 15172) possesses an extra pair of lower molars. 5

REMARKS: The only specimens of Choeroniscus minor accompanied by ecological data from our region were collected at two roosts near Nuevo San Juan. The first, encountered on 8 September 1999, consisted of two adult females under the buttresses of a fallen tree in secondary growth at the edge of a Matses swidden. The second roost, encountered on 20 September 1999, consisted of two adult males and one adult female perched on the underside of an unmodified frond of the stemless palm Attalea racemosa , about 1 m above the ground, in primary hilltop forest.

Our discovery of Choeroniscus minor roosting in foliage represents atypical behavior; all previously described roosts of this species have been

5 Supernumerary teeth usually occur unilaterally in glossophagines, but supernumerary teeth are known to occur bilaterally in numerous other bat taxa, especially nectarivorous and frugivorous species (Slaughter, 1970; Phillips, 1971; Bergmans and Van Bree, 1972; Bergmans, 1976; Giannini and Simmons, 2007).

found under fallen trees or inside hollow logs (Sanborn, 1954; Patterson, 1992; Simmons and Voss, 1998; Rengifo et al., 2013).

Figures

FIG. 10. Photographs of A, an adult Anoura caudifer captured at Quebrada Blanco; B, an adult Choeroniscus minor captured at Quebrada Blanco; C, an adult Glossophaga bakeri captured at El Chino Village; and D, an adult female (ROM 122150) G. soricina captured at Jenaro Herrera. Photographs by Marco Tschapka (A, B), Brock Fenton (C), and Burton Lim (D).