Hipposideros cyclops CYCLOPS LEAF-NOSED BAT

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between penis and anus, opening posteriorly just in front of anus. (Figure 74). ... from the central Congo Basin and it remains to be established if the species ...
Family HIPPOSIDERIDAE

Hipposideros cyclops CYCLOPS LEAF-NOSED BAT Fr. Phyllorhine cyclope; Ger. Zyklopen-Rundblattnase Hipposideros cyclops (Temminck, 1853). Esquisses Zool. sur la Côte de Guiné, p. 75. Boutry River, Ghana.

Taxonomy Originally Phyllorrhina cyclops. Species-group: cyclops. Synonyms: langi, micaceus. Subspecies: none recognized. Chromosome number: not known. Description Medium-sized microbat with noseleaf (posterior component roughly elliptical); blackish-brown with woolly, frosted pelage; ears separated; noseleaf with two median club-shaped processes; FA: 66.6 (59–75) mm. Not easily distinguished from H. camerunensis. Females significantly larger and heavier than !! in most body measurements. Pelage dense, soft, woolly; extending along proximal half of forearm; mid-dorsal hairs 11–13 mm (18– 380

19 mm at high altitudes). Dorsal pelage blackish-brown with white or silvery frosting; hairs blackish-brown with curly, white or silvery tip. Head greyish-brown with darker eye-rings. Ventral pelage paler than dorsal pelage with less conspicuous frosting. No orange-phase. Ears separated, comparatively medium to long but of medium relative length (42–53% of FA), narrow, medium to dark brown, inner margin convex, outer margin convex becoming concave near tip, tip narrowly pointed. Eyes comparatively large. Noseleaf as in Figure 68a. Posterior component divided into four cells by three vertical septa, and with a club-shaped process arising from middle of posterior edge. A second median club-shaped process arises

Hipposideros cyclops

from the central component above the nostrils. Internarial septum weakly developed, not concealing nostrils. Two well-developed lateral leaflets on each side, the lower pair continuous with the base of the posterior component. Frontal sac present and prominent in both sexes; opens vertically. It is lined with long, stiff, white hairs that form a conspicuous tuft when the sac is everted. At each side of the frontal sac there is a glandular patch or shallow sac. Wing and interfemoral membranes blackish-brown; skin on forearm, digits and tibia much paler reddish-brown. Fifth metacarpal 96 (92–100)% of third metacarpal. Tibia 42–52% of FA. Tail 45–49% of HB. Males have a (glandular?) sac lined with long, stiff, reddish-brown hairs, between penis and anus, opening posteriorly just in front of anus (Figure 74). Females lack this anal sac but have a patch of bare skin with scattered long and stiff hairs near the vagina. Skull robust, elongate with broad rostrum and elongated braincase; zygomatic arches massive; zygomatic width much greater than mastoid width. Rostrum broad. Sagittal crest low. Infraorbital (= anteorbital) foramen large, rounded and closed by a moderately wide bar (cf. H. camerunensis). Cochleae greatly enlarged, their breadth four times their distance apart (Hill 1963) (Figure 73d). Upper incisor slightly bicuspid. Upper canine powerful, relatively short (42 [37–46]% of C–M3, n = 8). Anterior upper premolar very small, fully displaced labially; canine and posterior premolar in contact. Anterior lower premolar ca. one-third to half the length and half the height of the posterior premolar.

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b

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Figure 74. Pubic region of adult ! Hipposideros cyclops showing (a) the anal sac in its invaginated state and (b) in its everted state. (c) Pubic region of adult " H. cyclops showing the patch of bare skin with scattered long, stiff hairs near the vagina. All based on Allen (1917a). The pubic region is the same in H. camerunensis.

Geographic Variation Variable throughout geographic range although no subspecies are currently recognized. Populations from drier habitats have significantly longer forearms than those from wetter habitats as exemplified (in Côte d’Ivoire) by bats from the Guinea Savanna BZ (Comoé N. P.) with FA: 67.1 (62–72) mm (n = 45) compared to those from the Rainforest BZ (Taï N. P.) with FA: 65.2 (62–70) mm (n = 28). Specimens from E DR Congo, W Uganda and N Burundi seem to attain larger dimensions, but samplesize is limited. Similar Species Only one other African Hipposideros has two median club-shaped processes on the noseleaf, and frosted blackishbrown woolly pelage (Table 15, p. 370): Hipposideros camerunensis. Usually larger (FA: 75.9 [74–80] mm; CrnC: 30.2 [29.2–31.5] mm). Infraorbital foramen smaller and closed by a narrow bar. Not known west of 9° E, but geographical ranges overlap from Cameroon to Kenya. Distribution Endemic to Africa. Recorded from the Rainforest BZ (Western, West Central and East Central Regions), the adjacent Northern and Eastern Rainforest–Savanna Mosaics and Afromontane–Afroalpine BZ, with an apparently isolated population in the Eastern Arc Mts and the Coastal Forest Mosaic BZ of Kenya and Tanzania. Recorded, somewhat disjunctly, from Senegal to coastal Kenya and Tanzania. Gaps in Guinea and Nigeria might reflect insufficient sampling. There are very few records from the central Congo Basin and it remains to be established if the species ranges throughout the entire Congolian rainforest zone. The record from Bamingui-Bangoran N. P., Central African Republic, appears to be very isolated.

Hipposideros cyclops

Habitat Recorded mainly from lowland rainforest but also from coastal forest, montane forest, swamp forest and mangroves vegetation zones. Also extends far into the Rainforest–Savanna Mosaic, and into the Guinea Savanna BZ where sufficiently large relict forests and gallery forests are present. Although mostly recorded in undisturbed forest, also found in secondary forest, highly degraded areas, and converted habitats such as cocoa and rubber plantations (Lang & Chapin 1917b, Jeffrey 1975, Fedden & 381

Family HIPPOSIDERIDAE

Macleod 1986, Schlitter et al. 1986, Juste & Ibáñez 1994, USNM records). Highest reported altitudes are 1000–1200 m on Mt Nimba (Liberia), 1100 m on Mt Kupé (Cameroon) (Hill 1968, Wolton et al. 1982) and 1950 m in Kibira N. P., Burundi (FMNH). Abundance Widespread and comparatively abundant in suitable habitat. The most frequently captured hipposiderid in Comoé N. P., Côte d’Ivoire, and the second most frequently captured hipposiderid in Taï N. P. Local distribution and abundance is probably determined by the availability of suitable day-roosts. Adaptations Flight moderately fast, manoeuvrability poor; energetic cost of flight probably high (J. Fahr & K. Soer unpubl.). By day, most often found roosting in spacious hollow trunks of standing trees, including Borassus-palms, Ceiba pentandra, Cola cordifolia, Cordia sp., Hallea stipulosa, Klainedoxa gabonensis, Macaranga sp., Pseudospondias microcarpa, Ricinodendron heudelotii and Terminalia superba (Decher & Fahr 2005a). Very occasionally found inside fallen logs, old wells and disused mines, and once found in a belfry. Never found in hollow Cynometra megalophylla in Comoé N. P. although this tree is very abundant in gallery forests and its hollow trunks seem suitable. Often shares day-roosts with other bats (Lissonycteris angolensis, Nycteris arge, N. major, Rhinolophus alcyone, R. landeri), anomalures (Idiurus macrotis, Anomalurus spp.), African Dormice (Gliridae) and Tullberg’s Softfurred Mouse Praomys tullbergi (Decher & Fahr 2005a). The recapture rate was 17% (n = 35) in Taï N. P. and 20% (n = 59) in Comoé N. P. (J. Fahr unpubl.). Most individuals were recaptured up to one year after marking, and two individuals were recaptured after three years. All were recaptured less than 400 m from the initial site, most less than 250 m, suggesting that home-ranges are very small (several ha) and that site-fidelity is unusually high. The eyes of H. cyclops are large in comparison with those of most other African hipposiderids, suggesting that vision plays a more important role in orientation than in other species of bats. Together with its sister species H. camerunensis, it is possibly the only African Hipposideros that does not have an orange-phase. The frosted pelage perhaps helps to camouflage these bats while they are exposed to predators during perch-hunting (see Foraging). Foraging and Food Insectivorous. Forages by fly-catching and, very rarely, by slow-hawking. Usually forages not far from the ground or vegetation. Median foraging height in Côte d’Ivoire (as determined by captures in mist-nets set 0–25 m above ground) was 1.9 (0.4– 23.6) m, n = 91, J. Fahr unpubl.). Most individuals were caught 1–8 m above ground, but six were caught between 13.5 and 23.6 m. They are specialized fly-catchers and rarely fly except when commuting from day-roosts to feeding areas, flying from one perch to another, or attacking prey. They emerge from their day-roosts comparatively early (18:00–18:30h) and fly to perches, such as tree trunks, branches and twigs, which are usually 2–6 m above ground. There they rotate from side to side while echolocating and scanning the surroundings for flying insects. Detected insects are captured in flight, and either carried back to the perch, or to the day-roost, where they are divested of their wings and other hard parts, and then consumed. Verschuren (1957) analysed discarded wings and other remains collected in Garamba N. P., NE DR Congo, and found predominantly hawk-moths (Sphingidae) and cicadas but also owl-flies (Neuroptera:Ascalaphidae), 382

flat-bugs (Heteroptera:Aradidae), wasps (Hymenoptera: Eumenidae) and beetles (Coleoptera: Scarabaeidae, Elateridae). Additionally, Verschuren (1957) found bark-lice (Psocoptera), moth-flies (Diptera: Psychodidae) and ants (Hymenoptera: Formicidae) in stomach contents. In Comoé N. P. these bats predominantly took hawk-moths, cicadas and beetles, but also ant-lions (Neuroptera: Myrmeleontidae), grasshoppers and crickets (Orthoptera: Acrididae, Gryllidae) and winged male driver-ants (Hymenoptera: Formicidae: Dorylus spp.) (K. Soer & J. Fahr unpubl.). Echolocation Call-shape CF/FM. CF-frequency in resting bats (Côte d’Ivoire) 59.7 (58.4–60.8) kHz (J. Fahr & N. Ebigbo unpubl.). The CF-frequency of 101–109 kHz given by Novick (1958b) is erroneous and possibly the result of the recording equipment at that time (J. Fahr unpubl.). Social and Reproductive Behaviour Roosts singly or in small to medium-sized groups comprised of 1–3 !! and several "" (Aellen 1952, Verschuren 1957, Fedden & Macleod 1986, J. Fahr unpubl.). The largest group found in Comoé N. P. consisted of 18 individuals (not sexed). Lang & Chapin (1917b) and Eisentraut (1956) reported group-sizes of 12 individuals. The mean ratio of !! to "" in colonies was 1 : 1.8 in Garamba N. P. (Verschuren 1957). Individuals roosting singly are mostly !!. The frontal sac in both sexes, and the anal sac in !!, are likely to play an important role in olfactory communication although the specific function is not known. The anal sac, when everted, emits a very strong, almost pungent odour. Not yet known if the odour is produced by glands or by bacterial fermentation of excretions.Young are not left in dayroosts during the night but are carried by their mothers, even during perch-hunting (J. Fahr pers. obs.). Reproduction and Population Structure Litter-size: one. Reproductive chronology uncertain. In the Northern Rainforest– Savanna Mosaic (Fintonia, NW Sierra Leone; Comoé N. P., NE Côte d’Ivoire; Garamba N. P., NE DR Congo), 11 of 14 adult "" were pregnant, two were lactating and one was neither pregnant nor lactating in Feb–Apr; 10 of 15 "" were lactating and five were neither pregnant nor lactating in May–Jun; none of 18 "" was pregnant or lactating in Oct–Nov; no data for other months (Verschuren 1957, J. Fahr unpubl., USNM). According to Verschuren (1957), in Garamba N. P., "" are in fairly close reproductive synchrony; births take place in mid-Mar, lactation ends in mid-May, and there is no evidence of a second parturition season; young are born with a FA ca. 25 mm. In the Rainforest BZ of Côte d’Ivoire, none of 18 adult "" was pregnant or lactating in Jan–Feb; 1 of 11 was pregnant, one was lactating and nine were neither pregnant nor lactating in Mar; none of 3 "" was pregnant or lactating in Jun; 8 of 14 "" were pregnant and six were neither pregnant nor lactating in Jul–Oct; 1 of 1 was lactating in Dec; no data for other months (J. Fahr unpubl., CM, MHNG, ROM, SMF, USNM). None of the females was found simultaneously lactating and pregnant (n = 34). These data are not conclusive but they are compatible with restricted seasonal monoestry in the Rainforest–Savanna Mosaic (with lactation coinciding with the onset of the wet season), and extended seasonal monoestry in the Rainforest BZ (with the majority of "" giving birth towards the end of the wet season).

Hipposideros fuliginosus

The ratio of !! to "" as determined by captures with mistnets (excluding recaptures) in Comoé N. P. was 1 : 0.6 (n = 55); in Taï N. P., it was 1 : 0.7 (n = 29; J. Fahr unpubl.). Predators, Parasites and Diseases Remains of one individual were found in scats of an unidentified small carnivore (probably genet Genetta sp.) in Central African Republic (Hutterer & Ray 1997). Ectoparasites include bat-flies Raymondia brachyphysa, R. intermedia (Diptera: Streblidae) and a mite Steatonyssus hipposideros (Acari: Macronyssidae) (Jobling 1956). In Taï N. P., 23% of the individuals (n = 35) were heavily infested with unidentified, bright orange mites (J. Fahr unpubl.). Conservation IUCN Category: Least Concern. Probably most threatened by destruction of suitable day-roosts and direct exploitation therein. Measurements Hipposideros cyclops FA (!!): 65.4 (61–75) mm, n = 54 FA (""): 68.0 (59–74) mm, n = 47 WS (c): 400 (374–425) mm, n = 13

TL (!!): 109.6 (99.0–133.0) mm, n = 45 TL (""): 113.1 (95.0–128.0) mm, n = 79 T: 83.6 (18–36) mm, n = 124 E: 33.5 (28–38) mm, n = 125 NL (breadth): 14.9 (12.9–15.7) mm, n = 8 Tib: 32.2 (29–35) mm, n = 20 HF: 20.1 (18–22) mm, n = 114 WT (!!): 29.2 (21–40) g, n = 81 WT (""): 34.8 (24–45.5) g, n = 91* CrnC: 28.2 (26.3–30.0) mm, n = 14 GWS: 15.3 (14.0–16.3) mm, n = 17 C–M3: 10.4 (9.9–10.8) mm, n = 12 Gambia, Guinea-Bissau, Liberia, Côte d’Ivoire, Ghana, Togo, Benin, Cameroon, DR Congo, Uganda, Burundi, Tanzania (FC, FMNH, IICT/CZ, MZUF, RMCA, ROM, SMF, SMNS, USNM) *Non-pregnant "". Pregnant "" up to 58 g Key References Decher & Fahr 2005a; Eisentraut 1956; Hill 1963; Lang & Chapin 1917b; Verschuren 1957. Jakob Fahr

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