Pipistrellus nanulus (Thomas, 1904)

Bates, Paul J. J., Cameron, Kenneth, Pearch, Malcolm J. & Hayes, Benjamin, 2013, A review of the bats (Chiroptera) of the Republic of Congo, including eight species new to the country, Acta Chiropterologica 15 (2), pp. 313-340 : 329

Pipistrellus nanulus (Thomas, 1904)

Tiny pipistrelle

Pipistrellus nanulus Thomas, 1904: 198 ; Efulen, Cameroons (= Cameroon).

New material

HZM.1.40189 , ♂, 4 August, 2012, Forest Trails, Lekoumou , 2°45.767’S, 13°36.365’E . This is the first authenticated record for Congo ( Appendix I ). Its relative abundance in Africa is not known ( Happold and Happold, 2013).

Description

A small, nondescript, species with a very short forearm length (26.1 mm) ( Table 2 ). The interfemoral and wing membranes are uniformly dark; the pelage is also uniformly dark on the back and buff-brown on the belly. The muzzle is thick and broadly rounded. In each ear, the tragus has a very slightly concave anterior border, a rounded tip, a smoothly rounded posterior border and a well developed basal lobule ( Fig. 8G ). The skull is short (GTL= 11.99 mm) ( Table 3 ), the rostrum is short and the braincase is low ( Fig. 10C ). The first upper incisor (I 2) is strongly bicuspid; the second (I 3) is unicuspid but with a well developed cingulum, it attains two-thirds the height of the secondary cusp of I 2 ( Fig. 10C ). The small, first upper premolar (P 2) is comparatively well developed and is slightly displaced internally; the canine and second premolar (P 4) are not in contact ( Fig. 10C ). The lower canine has a small but well-developed cusp on the anterior cingulum. The first lower premolar (P 2) is about equal in crown area and two-thirds the height of the second (P 4) ( Fig. 10C ). The baculum is long, with a bifid tip, a straight shaft and two, relatively ill-defined, basal lobules ( Fig. 11D ); this compares well with the baculum of the holotype of nanulus illustrated in Hill and Harrison (1987, Figure 7f ).

Taxonomic notes

According to Simmons (2005) there are no other named forms included in the synonymy of P. nanulus .

Figures

APPENDIX I A list of the forty-three bat species currently recorded from Congo, including citations in the literature and locality data. CS (Conservation status – NT: Near threatened; DD: Data deficient; LC: Least concern) is based on IUCN Red List of Threatened Species retrieved on 8 May, 2013. Two species listed here have not been assessed (na) by IUCN for their conservation status but rather have been included within other taxa: Triaenops afer in Triaenops persicus and Chaerephon leucogaster in Tadarida pumila. Superscripts associated with localities in column 4 refer to the superscripts for the literature cited in column 3

FIG. 8. Right tragus of (A): Glauconycteris alboguttata, HZM.1.40172, ♀; (B): G. beatrix, HZM.1.40181, ♀; (C): Hypsugo crassulus, HZM.1.40190, ♂; (D): Neoromicia brunnea, HZM.1.40191, ♂; (E): N. nana, HZM.321.40186, ♂; (F): N. tenuipinnis, HZM.7.40170, ♀; (G): Pipistrellus nanulus, HZM.1.40189, ♂; (H): Mimetillus moloneyi, HZM.10.40177, ♂; (I): Miniopterus inflatus, HZM.19.40182, ♂. Scale = 2 mm

FIG. 10. Skulls of three small vespertilionids, including lateral view of right upper incisors and occlusal view of left mandibular dentition (left) and left maxillary dentition (right) of (A): Hypsugo crassulus, HZM.1.40190, ♂; (B): Mimetillus moloneyi, HZM.10.40177, ♂ and (C) Pipistrellus nanulus, HZM.1.40189, ♂. Scales for skulls and occlusal views of toothrows (left and right) = 2 mm; scale for upper incisors (centre) = 1 mm

FIG. 11. Bacula of four pipistrelles. (A): Hypsugo crassulus, HZM.1.40190; (B): Neoromicia brunnea, HZM.1.40191; (C): N. nana, HZM.321.40186; and (D): Pipistrellus nanulus, HZM.1.40189. Scale = 1 mm

FIG. 7. Nycteris hispida, HZM.52.40188. (A): Anterior, left mandible; (B): left, upper incisors and canine; (C): right tragus; (D): baculum (dorsal view [left] and lateral view [right]). Scales for A, B, and D = 1 mm; scale for C = 2 mm