Caryologia. International Journal of Cytology, Cytosystematics and Cytogenetics 78(1): 3-26, 2025 Firenze University Press https://riviste.fupress.net/index.php/caryologiaCaryologia International Journal of Cytology, Cytosystematics and Cytogenetics ISSN 0008-7114 (print) | ISSN 2165-5391 (online) | DOI: 10.36253/caryologia-3365 Citation: Ngene, C. I., Okwuonu, E. S., Ogbonna, I. D., Ukwueze, C. B. & Ejere, V. C. (2025). Genomic por- traits: karyotyping of some Nigerian bat species. Caryologia 78(1): 3-26. doi: 10.36253/caryologia-3365 Received: March 7, 2025 Accepted: July 16, 2025 Published: October 1, 2025 © 2025 Author(s). This is an open access, peer-reviewed article pub- lished by Firenze University Press (https://www.fupress.com) and distrib- uted, except where otherwise noted, under the terms of the CC BY 4.0 License for content and CC0 1.0 Uni- versal for metadata. Data Availability Statement: All rel- evant data are within the paper and its Supporting Information files. Competing Interests: The Author(s) declare(s) no conflict of interest. ORCID CIN: 0000-0001-6757-8737 VCE: 0000-0003-2657-1912 Genomic portraits: karyotyping of some Nigerian bat species Chinedu Innocent Ngene1, Elijah Sunday Okwuonu1,*, Ifeanyi Damian Ogbonna2, Chinaza Blessing Ukwueze1, Vincent Chinwendu Ejere1 1 Department of Zoology and Environmental Biology, University of Nigeria, Nsukka, Enugu State, Nigeria 2 Department of Plant Science and Biotechnology, University of Nigeria, Nsukka, Enugu State, Nigeria *Corresponding author. Email: elijah.okwuonu@unn.edu.ng. Abstract. Chromosome studies were conducted on bat species in the Nsukka Local Government Area of Enugu State, Nigeria, to determine their karyotypes and assess relatedness. Chromosomes were isolated from the bone marrow and testes of various bat species using 0.4% colchicine for cell division arrest. A calibrated eye-piece grati- cule was used for counting and measuring chromosomes from prepared slides. Cal- culations for arm ratios and centromeric indices were performed to categorize chro- mosomes, and ideograms were created based on these measurements. Standard karyo- types for each species were established using photomicrographs of mitotic metaphase chromosomes. A total of eight bat species were sampled, representing the suborders Yinpterochiropera and Yangochiroptera. The species included Epomophorus wahlbergi, Epomophorus gambianus, Microteropus pusillus from Yinpterochiropera, and Nycteris major, Nycteris grandis, Nycteris arge, Scotophilus diaganii, and Scotophilus leucogaster from Yangochiroptera. The diploid chromosome numbers (2n) and fundamental num- bers (FN) were as follows: Epomophorus wahlbergi (2n=35, FN=70), Epomophorus gambianus (2n=36, FN=79), Microteropus pusillus (2n=36, FN=79), Nycteris major (2n=40, FN=80), Nycteris grandis (2n=42, FN=82), Nycteris arge (2n=40, FN=78), Sco- tophilus diaganii (2n=36, FN=45), and Scotophilus leucogaster (2n=36, FN=54). Vari- ations in 2n and FN were attributed to centric fission and loss of p arm segments in some chromosomal pairs, leading to different morphological traits observed in the bat species. The study highlights the rich diversity of bat species in Nsukka and supports the use of karyotyping as an effective method for species differentiation. Keywords: chromosomes, megabats, centric fission, Epomophorus, Microteropus, Nyc- teris, Scotophilus. INTRODUCTION Bats, constituting a significant percentage of living mammals, belong to the order Chiroptera, which is the second most diverse order of mammals (Wilson and Reeder 2005; Stevens and Willig 2002; Simmons and Conway 2003). They exhibit unique adaptations such as flight, echolocation, and a https://riviste.fupress.net/index.php/caryologia https://doi.org/10.36253/caryologia-3365 https://doi.org/10.36253/caryologia-3365 https://www.fupress.com https://creativecommons.org/licenses/by/4.0/legalcode https://creativecommons.org/publicdomain/zero/1.0/legalcode https://orcid.org/0000-0001-6757-8737 https://orcid.org/0000-0003-2657-1912 mailto:elijah.okwuonu@unn.edu.ng 4 Chinedu Innocent Ngene et al. wide range of ecological roles, feeding on various food sources like fish, insects, blood, nectar, and fruit (Fenton et al. 2016; Teeling et al. 2012). Bats play essential eco- logical roles, including seed dispersal, pest control, and pollination of crops (e.g., agave for tequila production) (McCracken et al. 2012; Bumrungsri et al. 2013). Bats are also known reservoirs for several deadly viruses, including Ebola, SARS, rabies, and MERS, often remaining asymptomatic (Wang et al. 2011; Drexler et al. 2012; Anthony et al. 2017). Remarkably, they have long lifespans and low cancer rates, which may provide insights into aging and longevity (Austad 2010; Wang et al. 2011). The taxonomic classification of bats has evolved, with a shift from the “wide” polytypic to the “narrow” monotypic species concept due to advancements in mor- phological and karyological techniques (Strelkov 2006; Kruskop 2005). Recent taxonomic revisions have identi- fied 14 new Far Eastern bat species (Kruskop et al. 2012; Ruedi et al. 2015). However, African bats remain under- researched, with over 70% of fossil data missing, compli- cating conservation efforts (Teeling et al. 2012). This study aimed to investigate the cytotaxonomy of bat species in Nsukka LGA, Enugu State, Nigeria, by determining chromosome numbers and characteristics, constructing karyotypes, and assessing species related- ness, addressing the lack of cytotaxonomic data in this region. MATERIALS AND METHODS The study was conducted in the Nsukka Local Gov- ernment Area (LGA) of Enugu State, Nigeria, within the northern senatorial zone (Figure 1). Nsukka LGA is characterized by its green, steep terrain and includes villages such as Alor-Uno, Ede-Oballa, and Okpuje, cov- ering an area of 1,810 km² with a population of 309,448 (ANON, 2006). The study sites included Obimo, Ibagwa- Ani, Nsukka, and Obukpa (Figure 2). DATA ANALYSIS The data collected were analyzed based on observa- tions from Abraham and Prasad (1983) and Adegoke and Ejere (1991). These observations facilitated the classifica- tion of chromosomes into four groups: metacentric, sub- metacentric, subtelocentric, and acrocentric. Additional- ly, the relationships among the species were determined by measuring the chromosomes’ relative lengths and centromeric indices. Trapping of experimental animals Bats were trapped using a triple high mist net and a harp trap, following methods from Denys et al. (2013). Traps were set across potential flight paths for one night, checked every 10 to 20 minutes to prevent entanglement. Two bats (one male and one female) from each species were sacrificed for chromosome studies, with an addi- tional specimen kept as a voucher. Experimental design The standard colchicine method was employed to prepare metaphase chromosome samples, following the protocol of Ejere and Adegoke (2001) with slight modi- fications. This procedure involved administering an intraperitoneal injection of 0.1 ml of 0.4% colchicine to each bat species for 2 hours to halt mitotic cell divi- sion. After euthanizing the bats with iso-fluorine, the hind leg bones were dissected and trimmed. Bone mar- row was extracted using a heparinized syringe contain- ing 3 ml of 0.55% KCl, which was then placed in labeled 15 ml centrifuge tubes, homogenized, and allowed to sit for 15 minutes. The resulting suspensions were cen- trifuged for 5 minutes at 1500 rpm, and the supernatant was discarded, leaving 0.5 ml of liquid in which the cells were resuspended. The cells were fixed with fresh cold Figure 1. Map of Enugu State showing Nsukka local government area. Source: Geospatial Analysis Mapping and Environmental Research Solution (2018). 5Genomic portraits: karyotyping of some Nigerian bat species Carnoy’s fixative and allowed to sit for about 30 seconds before undergoing centrifugation again, with the super- natant removed. This centrifugation process in the fixa- tive was repeated twice more, after which the cells were resuspended and diluted with the fixative prior to being spread on glass slides. The slides were stained in a Cop- lin jar with 5 ml of Giemsa stain for 30 minutes, rinsed with tap water, and then placed in a slide warmer at 60 °C for 2 hours. Stained slides were examined for divid- ing cells under a light microscope at 10x magnification. Well-separated, countable metaphase chromosomes were measured and photographed under oil immersion at approximately 1000x magnification. The resulting pho- tomicrographs were used to construct karyotypes (Ade- goke and Ejere 1991; Ejere and Adegoke 2001). Morphological identification Morphological identification was performed accord- ing to Happold and Happold (2013), and specimens were deposited at the University of Nigeria’s Zoology Muse- um, tagged Ew, Ep, Mp, Nm, Ng, Na, Sa, and Sl. Ethical approval Ethical standards were upheld as per the Faculty of Biological Science Ethics and Biosafety Committee, Uni- versity of Nigeria, Nsukka (Ref. Number: UNN/FBS/ EC/1013). RESULTS During the study, various species of bats from the families Yinpterochiropera and Yangochiroptera were identified in Nsukka LGA. The Yinpterochiropera fam- ily included Epomophorus wahlbergi, Epomophorus gam- bianus, and Microteropus pusillus, while the Yangochi- roptera family featured Nycteris major, Nycteris grandis, and Nycteris arge. The Vespertilionidae family included Scotophilus leucogaster and Scotophilus diaganii. Table 1 presents the chromosomal numbers and fundamental numbers (FN) along with karyotype diagrams. For each bat species analyzed, distinct karyotypes were established based on size. For example, in Epomo- phorus wahlbergi, the karyotype was categorized into three groups, with group one comprising four large Figure 2. Map of Nsukka Local Government Area showing the study area (Obimo, Ibagwa-ani, Nsukka and Obukpa). 6 Chinedu Innocent Ngene et al. chromosomes, group two including medium-sized chro- mosomes, and group three consisting of smaller chromo- somes (Table 2). Similarly, Epomophorus gambianus and Microteropus pusillus displayed comparable karyotypic structures, with varying numbers of chromosomes in each size category (Tables 3 and 4). Nycteris major, Nycteris grandis, and Nycteris arge were also analyzed, revealing three main size groups in their karyotypes (Tables 5, 6 and 7). For Nycteris major, it was noted that males and females had dis- tinct chromosome arrangements and FN. Compari- sons between species showed that Yinpterochiropteran bats shared similarities, particularly in their larger chromosomes. Notably, Epomophorus wahlbergi and Epomophorus gambianus had similar chromosome structures, especially in larger and some medium- sized chromosomes. Scotophilus diaganii and Scotophilus leucogaster each had a single large chromosome (Tables 8 and 9), while other species exhibited a range of large and small chro- mosomes, indicating potential phylogenetic relation- ships. Differences in chromosomal counts and struc- Table 1. Diploid chromosome and fundamental numbers of various sampled bat species from Nsukka LGA, Nigeria. S/N Bat species Mitotic metaphase chromosome spread Karyotype Diagram Diploid chromosome number Funda-mental number (FN) 1. Epomophorus wahlbergi Plate 1A Plate 1B Plate 1C 2n=35 70 2. Epomophorus gambianus Plate 2A Plate 2B Plate 2C 2n=36 79 3. Epomophorus (Microteropus) pusillus Plate 3A Plate 3B Plate 3C 2n=36 79 4. Nycteris major Plate 4A & Plate 4B Plate 4C (male) & Plate 4D (female) Plate 4E (male) & Plate 4F (female) 2n=40 80 5. Nycteris grandis Plate 5A Plate 5B (female) Plate 5C 2n=42 82 6. Nycteris arge Plate 6A Plate 6B Plate 6C 2n=40 78 7. Scotophilus diaganii Plate 7A Plate 7B Plate 7C 2n=36 45 8. Scotophilus leucogaster Plate 8A Plate 8B Plate 8C 2n=36 54 Table 2. Epomophorus wahlbergi’s chromosomal nomenclature based on centromeric indices. Chromosome Number Short Arm (S) % Long Arm (L) Total Length (C) % Centromeric Index (I) Nomenclature 1. 5.40 9.00 14.40 37.50 Nearly submedian (-) 2. 7.20 7.20 14.40 50.00 Median 3. 6.30 7.20 13.50 46.67 Nearly median 4. 4.50 7.20 11.70 38.46 Nearly median 5. 3.60 6.30 9.90 36.36 Nearly submedian (-) 6. 2.80 6.56 9.36 29.91 Nearly submedian (-) 7. 3.60 5.76 9.36 38.46 Nearly median 8. 3.96 5.40 9.36 42.31 Nearly median 9. 3.60 5.40 9.00 40.00 Nearly median 10. 2.60 6.40 9.00 28.89 Nearly submedian (-) 11. 2.50 5.60 8.10 30.86 Nearly submedian (-) 12. 3.60 4.32 7.92 45.45 Nearly median 13. 2.70 3.60 6.30 42.86 Nearly median 14. 2.70 3.60 6.30 42.86 Nearly median 15. 1.80 3.60 5.40 33.33 Nearly submedian (-) 16. 1.80 1.80 3.60 50.00 Median 17. 1.80 1.80 3.60 50.00 Median X. 3.60 3.60 7.20 50.00 Median The chromosomal centromeric index (i) was calculated using the method i = 100s/c. In the above table, the chromosome lengths were measured in microns as described under materials and methods, and then individually converted to percentages of total complement 7Genomic portraits: karyotyping of some Nigerian bat species tural characteristics were highlighted, with telocentric chromosomes prevalent in the Scotophilus species. Table 10 summarizes that all bat species had at least one large chromosome, with specific similarities and differences noted in their karyotypic features (Figure 3). Table 3. Epomophorus gambianus chromosomal nomenclature based on centromeric indices. Chromosome Number Short Arm (S) % Long Arm (L) Total Length (C) % Centromeric Index (I) Nomenclature 1. 5.40 7.20 12.60 42.86 Nearly median 2. 6.30 6.30 12.60 50.00 Median 3. 5.40 6.84 12.24 44.12 Nearly median 4. 5.40 6.30 11.70 46.15 Nearly median 5. 3.60 6.30 9.90 36.36 Nearly submedian (-) 6. 2.50 7.40 9.90 25.25 Nearly submedian (-) 7. 3.60 6.30 9.90 36.36 Nearly submedian (-) 8. 3.60 5.40 9.00 40.00 Nearly median 9. 4.50 4.50 9.00 50.00 Median 10. 3.60 5.40 9.00 40.00 Nearly median 11. 3.60 4.50 8.10 44.44 Nearly median 12. 2.70 3.96 6.66 40.54 Nearly median 13. 1.50 3.60 5.40 33.33 Nearly submedian (-) 14. 1.80 3.60 5.40 33.33 Nearly submedian (-) 15. 1.80 3.60 5.40 33.33 Nearly submedian (-) 16. 0.80 2.80 3.60 22.22 Nearly submedian (+) 17. 0.00 3.60 3.60 0.00 Terminal X. 3.78 3.78 7.56 50.00 Median X. 3.78 3.78 7.56 50.00 Median Table 4. The nomenclature of the chromosomes of Epomophorus (Microteropus) pusillus using the centromeric indices. Chromosome Number Short Arm (S) % Long Arm (L) Total Length (C) % Centromeric Index (I) Nomenclature 1. 6.40 8.00 14.40 44.44 Nearly median 2. 7.20 7.20 14.40 50.00 Median 3. 6.30 7.20 13.50 46.67 Nearly median 4. 4.50 5.40 9.90 45.45 Nearly median 5. 4.14 5.40 9.54 43.40 Nearly median 6. 3.60 5.76 9.36 38.46 Nearly median 7. 3.60 5.76 9.36 38.46 Nearly median 8. 1.80 5.76 7.56 23.81 Nearly submedian (+) 9. 2.20 5.36 7.56 29.10 Nearly submedian (-) 10. 3.60 3.96 7.56 47.62 Nearly median 11. 3.60 3.60 7.20 50.00 Median 12. 3.40 3.80 7.20 47.22 Nearly median 13. 2.70 3.60 6.30 42.86 Nearly median 14. 1.80 2.70 4.50 40.00 Nearly median 15. 1.80 2.70 4.50 40.00 Nearly median 16. 1.80 1.80 3.60 50.00 Median 17. 0.00 3.60 3.60 0.00 Terminal X. 3.60 3.60 7.20 50.00 Median X. 3.60 3.60 7.20 50.00 Median 8 Chinedu Innocent Ngene et al. Table 5. The nomenclature of the chromosomes of Nycteris major using the centromeric indices. Chromosome Number Short Arm (S) % Long Arm (L) Total Length (C) % Centromeric Index (I) Nomenclature 1. 5.40 9.90 15.30 35.29 Nearly sub-median (-) 2. 5.40 8.64 14.04 38.46 Nearly median 3. 6.30 6.30 12.60 50.00 Median 4. 5.40 5.40 10.80 50.00 Median 5. 3.60 7.20 10.80 33.33 Nearly submedian (-) 6. 3.60 6.30 9.90 36.36 Nearly submedian (-) 7. 2.40 7.50 9.90 24.24 Nearly submedian (+) 8. 3.60 5.76 9.36 38.46 Nearly median 9. 3.60 5.76 9.36 38.46 Nearly median 10. 3.60 5.40 9.00 40.00 Nearly median 11. 3.60 4.50 8.10 44.44 Nearly median 12. 1.80 6.30 8.10 22.22 Nearly sub median (+) 13. 1.80 5.40 7.20 25.00 Submedian 14. 3.42 3.78 7.20 24.62 Nearly submedian (+) 15. 2.70 3.60 6.30 42.86 Nearly median 16. 2.70 3.60 6.30 42.86 Nearly median 17. 2.70 3.60 6.30 42.86 Nearly median 18. 1.80 3.60 5.40 33.33 Nearly submedian (-) 19. 1.80 3.60 5.40 33.33 Nearly submedian (-) X. 3.60 3.60 7.20 50.00 Median X. 3.60 3.60 7.20 50.00 Median Y. 0.00 3.60 3.60 0.00 Terminal Table 6. The nomenclature of the chromosomes of Nycteris grandis using the centromeric indices. Chromosome Number Short Arm (S) % Long Arm (L) Total Length (C) % Centromeric Index (I) Nomenclature 1. 7.20 9.00 16.20 44.44 Nearly median 2. 7.20 7.20 14.40 50.00 Median 3. 6.75 6.75 13.50 50.00 Median 4. 6.30 6.30 12.60 50.00 Median 5. 6.30 6.30 12.60 50.00 Median 6. 5.40 7.20 12.60 42.86 Nearly median 7. 5.85 5.85 11.70 50.00 Median 8. 4.50 6.84 11.34 39.68 Nearly median 9. 3.96 7.20 11.16 34.14 Nearly submedian (-) 10. 5.04 5.40 10.80 46.67 Nearly median 11. 4.50 5.40 9.90 45.45 Nearly median 12. 3.60 6.30 9.90 36.36 Nearly submedian (-) 13. 1.80 7.20 9.00 20.00 Nearly submedian (+) 14. 3.60 5.40 9.00 36.36 Nearly submedian (-) 15. 2.80 6.20 9.00 31.11 Nearly submedian (-) 16. 1.80 7.20 9.00 20.00 Nearly submedian (+) 17. 3.60 5.40 9.00 36.36 Nearly submedian (-) 18. 2.70 3.60 6.30 42.86 Nearly median 19. 2.70 3.60 6.30 42.36 Nearly median 20. 0.00 2.70 2.70 0.00 Terminal X. 3.80 3.80 7.60 50.00 Median X. 3.80 3.80 7.60 50.00 Median 9Genomic portraits: karyotyping of some Nigerian bat species Table 7. The nomenclature of the chromosomes of Nycteris arge using the centromeric indices Chromosome Number Short Arm (S) % Long Arm (L) Total Length (C) % Centromeric Index (I) Nomenclature 1. 5.40 9.00 14.40 37.50 Nearly submedian (-) 2. 5.40 7.20 12.60 42.86 Nearly median 3. 3.60 7.20 10.80 33.33 Nearly submedian (-) 4. 5.40 5.40 10.80 50.00 Median 5. 3.96 5.40 9.36 42.31 Nearly median 6. 3.60 5.76 9.36 38.46 Nearly median 7. 3.78 5.40 9.18 41.18 Nearly median 8. 3.60 5.40 9.00 40.00 Nearly median 9. 3.60 5.40 9.00 40.00 Nearly median 10. 3.60 5.04 8.64 41.67 Nearly median 11. 3.60 4.50 8.10 44.44 Nearly median 12. 3.60 4.32 7.92 45.45 Nearly median 13. 3.60 3.60 7.20 50.00 Median 14. 3.00 4.20 7.20 41.67 Nearly median 15. 2.40 4.80 7.20 33.33 Nearly submedian (-) 16. 3.24 3.60 6.84 47.37 Nearly median 17. 2.88 3.60 6.48 44.44 Nearly median 18. 2.70 3.60 6.30 43.86 Nearly median 19. 0.00 3.60 5.40 0.00 Terminal X. 3.60 3.60 7.20 50.00 Median X. 3.60 3.60 7.20 50.00 Median Table 8. The nomenclature of the chromosomes of Scotophilus diagonal using the centromeric indices Chromosome Number Short Arm (S) % Long Arm (L) Total Length (C) % Centromeric Index (I) Nomenclature 1. 5.20 5.60 10.80 48.15 Nearly median 2. 3.60 5.40 9.00 40.00 Nearly median 3. 2.20 5.00 7.20 30.56 Nearly submedian (-) 4. 1.80 5.40 7.20 25.00 Submedian 5. 0.00 6.30 6.30 0.00 Terminal 6. 0.00 6.30 6.30 0.00 Terminal 7. 0.00 6.30 6.30 0.00 Terminal 8. 0.00 6.30 6.30 0.00 Terminal 9. 0.00 6.30 6.30 0.00 Terminal 10. 0.00 6.30 6.30 0.00 Terminal 11. 0.00 6.30 6.30 0.00 Terminal 12. 0.00 6.30 6.30 0.00 Terminal 13. 0.00 6.30 6.30 0.00 Terminal 14. 0.00 5.40 5.40 0.00 Terminal 15. 0.00 5.40 5.40 0.00 Terminal 16. 0.00 4.50 4.50 0.00 Terminal 17. 0.00 4.50 4.50 0.00 Terminal X. 2.80 2.80 5.60 50.00 Median Y. 0.00 3.60 3.60 0.00 Terminal 10 Chinedu Innocent Ngene et al. Table 9. The nomenclature of the chromosomes of Scotophilus lecuogaster using the centromeric indices Chromosome Number Short Arm (S) % Long Arm (L) Total Length (C) % Centromeric Index (I) Nomenclature 1. 5.40 6.30 11.70 46.15 Nearly median 2. 4.50 5.40 9.90 45.45 Nearly median 3. 3.60 5.40 9.00 40.00 Nearly median 4. 1.80 7.20 9.00 20.00 Nearly submedian (+) 5. 2.70 5.40 8.10 33.33 Nearly sub median (-) 6. 0.00 8.10 8.10 0.00 Terminal 7. 0.00 7.20 7.20 0.00 Terminal 8. 0.00 7.20 7.20 0.00 Terminal 9. 0.00 7.20 7.20 0.00 Terminal 10. 0.00 7.20 7.20 0.00 Terminal 11. 3.00 4.20 7.20 41.67 Nearly median 12. 0.00 7.20 7.20 0.00 Terminal 13. 0.00 6.64 6.84 0.00 Terminal 14. 0.00 6.84 6.84 0.00 Terminal 15. 1.80 3.60 5.40 33.33 Nearly submedian (-) 16. 1.80 3.60 5.40 33.33 Nearly submedian (-) 17. 0.00 3.60 3.60 0.00 Terminal X. 4.05 4.05 8.10 50.00 Median X. 4.05 4.05 8.10 50.00 Median Table 10. A table showing the relationship among the bat species using autosomal chromosomes Chromosome Number Epomophorus wahlbergi Epomophorus gambianus Microteropus pusillus Nycteris major Nycteris grandis Nycteris species Nycteris arge Scotophilus diaganii (yellow- bellied bat) Scotophilus lecuogaster (white-bellied bat) 1. L, Sm L, Sm L, Sm L, Ac L, Sm L, Ac L, Ac L, Mc L, Sm 2. L, Mc L, Mc L, Mc L, Sm L, Mc L, Ac L, Sm M, Sm M, Sm 3. L, Sm L, Sm L, Sm L, Mc L, Mc L, Ac L, Ac M, Tc M, Sm 4. L, Sm L, Sm M, Sm L, Mc L, Mc L, Sm L, Mc M, Ac M, Sm 5. M, Ac M, Ac M, Sm L, Ac L, Mc L, Sm M, Sm S, Tc M, Sm 6. M, Ac M, Ac M, Sm M, Ac L, Sm L, Ac M, Sm S, Tc M, Ac 7. M, Sm M, Ac M, Sm M, Ac L, Mc L, Ac M, Sm S, Tc M, Tc 8. M, Sm M, Sm M, Ac M, Mc L, Sm L, Mc M, Sm S, Tc M, Tc 9. M, Sm M, Mc M, Ac M, Mc L, Ac L, Sm M, Sm S, Tc M, Tc 10. M, Ac M, Sm M, Sm, M, Mc L, Sm M, Ac M, Sm S, Tc M, Tc 11. M, Ac M, Sm M, Mc M, Mc M, Sm M, Sm M, Sm S, Tc M, Tc 12. M, Sm S, Sm M, Sm M, Ac M, Ac M, Sm M, Sm S, Tc M, Tc 13. S, Mc S, Ac M, Ac M, Ac M, Ac M, Sm M, Mc S, Tc S, Tc 14. S, Sm S, Ac S, Sm M, Ac M, Ac M, Sm M, Sm S, Tc S, Tc 15. S, Ac S, Ac S, Sm S, Sm M, Ac M, Sm M, Sm S, Tc S, Ac 16. S, Mc S, Ac S, Sm S, Sm M, Ac M, Sm S, Sm S, Tc S, Ac 17. S, Mc S, Tc S, Tc S, Sm M, Ac M, Sm S, Sm S, Tc S, Tc 18. S, Ac S, Sm S, Sm S, Sm 19. S, Ac S, Sm S, Tc S, Ac 20. S, Tc S, Tc 21. S, Tc Key: L = Large; M = Medium; S = Small; Submetacentric = Sm; Metacentric = Mc; Acrocentic = Ac; Telocentric =Tc. 11Genomic portraits: karyotyping of some Nigerian bat species DISCUSSION This study identified bat species from the Megachi- roptera (frugivorous bats) and Microchiroptera (insec- tivorous bats), each exhibiting one large chromosome. The diploid chromosome number (2n) of the bat species analyzed ranged from 35 to 42, aligning with the known chromosome diversity in bats (2n=14 to 64) (Cibele et al. 2017). This indicates a high degree of conservation in diploid chromosome numbers among bat groups (Cibele et al. 2017). The Pteropodidae family (fruit bats) displayed a chromosome range of 35-36, similar to the 2n range of 24-58 reported by Sotero-Caio et al. (2017). Specifically, Epomophorus wahlbergi was found to have 2n=35 and FN=70, differing from Kenyan and Zimbabwean species with 2n=36, FN=68 (Dulic and Mutere 1975; Peterson and Nagorsen 1975). This study confirms Epomopho- rus wahlbergi follows the X0 sex chromosome system. Epomophorus gambianus exhibited 2n=36 and FN=70, aligning with the XX system for Epomophorus species. Microteropus pusillus currently known as Epomophorus pusillus also displayed 2n=36 and FN=70, contrasting with prior reports of 2n=35, FN=64 in Cameroon (Haid- uk et al. 1981). The Nycteridae family was characterized by varying diploid numbers, with Nycteris major showing 2n=40 (FN=79 for males, FN=80 for females) and Nycteris grandis reported as 2n=42 (FN=82) (Porter et al. 2010). There were notable morphological and chromosomal differences observed among species within this fam- ily, which is classified into Nycteris with diploid counts ranging from 2n=34 to 42 (Denys et al. 2013). In the Vespertilionidae family, Scotophilus diaganii presented 2n=36 and FN=45, consistent with South Afri- can specimens but differing in FN (52 and 50) reported by Schlitter et al. (1980) and Ruedas et al. (1990). Scotophilus leucogaster’s karyotype showed 2n=36, FN=54, differing Figure 3. Cluster relationship of the bat species using chromosomal indices. Key: • Epomophorus wahlbergi = E.w., • Epomophorus gambianus = E.g., • Microteropus pusillus = M.p., • Nycteris major = N.m., • Nycteris grandis = N.g., • Nyceris arge = N.a., • Sctotophilus diaganii = S.d., and Scotophilus lecuogaster = s.l 12 Chinedu Innocent Ngene et al. from reports of 50 for specimens in Namibia and Burkina Faso (Ruedas et al. 1990; Volleth et al. 2006). The chromosomes of these bat species differ from those of lizards, suggesting genus-specific variations. As research advances to molecular levels, previously mis- classified species are being correctly positioned within taxonomic frameworks, revealing geographic influences on chromosomal variations (Foley et al. 2017). Notable patterns of karyotype similarities were identified across species, potentially linked to cryptic species and geo- graphical isolation (Cibele et al. 2017). In summary, this detailed study of the cytogenetics of bat species in Nsukka reported karyotypes for eight species: Epomophorus wahlbergi (2n=35), Epomophorus gambianus (2n=36), Microteropus pusillus (2n=36), Nyc- teris major (2n=40), Nycteris grandis (2n=42), Nycteris arge (2n=40), Scotophilus diaganii (2n=36), and Scotophi- lus leucogaster (2n=36). Further research utilizing mod- ern cytogenetic techniques is needed to fill knowledge gaps in this field. AUTHOR CONTRIBUTION STATEMENT Chinedu Innocent Ngene and Vincent Chinwendu Ejere: conceptualization of the project research; Chinedu Innocent Ngene and Elijah Sunday Okwuonu: data col- lection; Chinedu Innocent Ngene: lab work; Chinedu Innocent Ngene, Elijah Sunday Okwuonu, Ifeanyi Dami- an Ogbonna and Chinaza Blessing Ukwueze: manu- script drafting and review ACKNOWLEDGEMENTS We thank the Small Mammal Conservation Organi- zation (SMACON) for providing harp traps and mist nets. We also thank Johnmartin Oforkansi, Samson Ugwuanyi, Elijah Okwuonu, Osita Ezeugwu, and Fran- cis Abonyi, for assisting in the field. Finally, we are grateful to Professor Vincent C. Ejere, and the late Prof. Felicia C. Eke, for providing chemicals, equipment, and instructions for chromosomal extractions. REFERENCES Abraham Z. & Prasad PN. (1983). A system of chromo- some classification and nomenclature. Cytologia, 48, 95–101. https://doi.org/10.1508/cytologia.48.95. Adegoke JA. & Ejere VC. Description of the chromo- somes of three lizard species belonging to the genus, Mabuya (Scincidae, Reptilia). Caryologia, 44, 333– 342. https://doi.org/10.1080/00087114.1991.1079719 9. Anthony SJ, Johnson CK, Greig DJ, Kramer S, Che X et al. (2017). Global patterns in coronavirus diver- sity. Virus Evolution, 3(1), vex012. https://doi. org/10.1093/ve/vex012. Austad SN. (2010). Methuselah’s zoo: how nature pro- vides us with clues for extending human health span. Journal of Comparative Pathology, 142, S10–S21. htt- ps://doi.org/10.1016/j.jcpa.2009.10.024. Baker RJ. & Bickham JW. (1980). Karyotypic evolu- tion in bats: Evidence of extensive and conserva- tive chromosomal evolution in closely related taxa. Systematic Zoology, 29(3), 239–253. https://doi. org/10.2307/2412660. Bickman JW. (1979). Banded Karyotypes of 11 Species of American Bats (Genus Myotis). Journal of Mammal- ogy, 60, 350 – 363. https://doi.org/10.2307/1379807. Brook CE. & Dobson AP. (2015). Bats as “special” res- ervoirs for emerging zoonotic pathogens. Current Trends Microbiology, 23(3), 172–180. Bulkina TM. & Kruskop SV. (2009). Search for morpho- logical differences between genetically distinct brown long-eared bats (Plecotus auritus s. lato, Vespertilioni- dae). Plecotus, 11-12: 3–13. Bumrungsri S, Lang D, Harrower C, Sripaoraya E, Kitpipit K and Racey PA. (2013). The dawn bat, Eonycteris spelaea Dobson (Chiroptera: Ptero- podidae) feeds mainly on pollen of economi- cally important food plants in Thailand. Acta Chiropterologica, 15(1), 95–104. https://doi. org/10.3161/150811013X667894. Cibele G. Sotero-Caio, Robert J. Baker, and Marianne Volleth (2017). Chromosomal evolution in Chi- roptera. Genes, 8, 273. https://doi.org/10.3390/ genes8100272. Denys C, Kadjo B, Missoup AD, Monadjem A and Ani- skine V. (2013). New records of bats (Mammalia: Chiroptera) and karyotypes from Guinean Mount Nimba (West Africa). Italian Journal of Zoology, 80(2): 279–290. https://doi.org/10.1080/11250003.20 13.775367. Drexler JF, Corman VM, Muller MA, Maganga GD, Vallo P, Binger T. et al. (2012). Bats host major mammalian paramyxoviruses. Nature Communications, 3, 796. https://doi.org/10.1038/ncomms1796. Dulic B. & Mutere FA. (1975). Les chromosome de tro’s especes, des, megachropteres (mamm ba, chiroptera) d’Afrique orientale. Caryologia, 26, 389–396. Eick GN, Jacobs DS, Yang F and Volleth M. (2007). Kar- yotypic differences on sibling species of Scotophi- https://doi.org/10.1508/cytologia.48.95 https://doi.org/10.1080/00087114.1991.10797199 https://doi.org/10.1080/00087114.1991.10797199 https://doi.org/10.1093/ve/vex012 https://doi.org/10.1093/ve/vex012 https://doi.org/10.1016/j.jcpa.2009.10.024 https://doi.org/10.1016/j.jcpa.2009.10.024 https://doi.org/10.2307/2412660 https://doi.org/10.2307/2412660 https://doi.org/10.2307/1379807 https://doi.org/10.3161/150811013X667894 https://doi.org/10.3161/150811013X667894 https://doi.org/10.3390/genes8100272 https://doi.org/10.3390/genes8100272 https://doi.org/10.1080/11250003.2013.775367 https://doi.org/10.1080/11250003.2013.775367 https://doi.org/10.1038/ncomms1796 13Genomic portraits: karyotyping of some Nigerian bat species lus from South Africa (Vespertilionidae, Chiroptera, Mammalia). Cytogenetic and Genome Research, 118(1), 72–77. https://doi.org/10.1159/000106444. Ejere VC. & Adegoke JA. (2001). Karyological study of banded gecko, Hemidactylus fasciatus fasciatus Gray (Gekkonidae, Reptilia). Cytologia, 66, 133–137. htt- ps://doi.org/10.1508/CYTOLOGIA.66.133. Fahr J. (2013). Rhinolophus maclaudi Maclaud’s horse- shoe bat in mammals of Africa. In: Happold M & Happold DCD (Editors). Mammals of Africa, Volume IV: Hedgehogs, Shrews and Bats. Bloomsbury, Lon- don, England. Fenton MB, Grinnell AD, Popper AN and Fay RR. (2016). Bat Bioacoustics. Springer, New York. Foley NM, Goodman SM, Whelan CV, Peuchmaille SJ and Teeling T. (2017). Towards navigating the mino- taur’s labyrinth: cryptic diversity and taxonomic revi- sion within the speciose genus Hipposideros (Hippo- sideridae). Acta Chiropterologica, 19, 1–18. https:// doi.org/10.3161/15081109ACC2017.19.1.001. Geospatial Analysis Mapping and Environmental Research Solution (GAMERS). 2018. Map of Enugu State, Nigeria. Available at: https://www.gamers.com. ng/map-of-enugu-state-nigeria/. Accessed on 22nd August 2019. Haiduk MW, Baker RJ, Robbins L and Shlitter DA. (1981). Chromosomal evolution in African Megachi- raptera: G-and C-band assessment of the magnitude of change in similar standard karyotypes. Cytoge- netics & Cell Genetics, 29(4), 221–232. https://doi. org/10.1159/000131573 Happold M. & Happold DCD. (2013). Mammals of Africa. Volume IV: Hedgehogs, Shrews and Bats. Bloomsbury Publishing, London, United Kingdom. 800 pp. Hsu TC. & Arrighi FE. (1971). Distribution of consti- tutive heterochromatin in mammalian chromo- somes. Chromosoma, 34(3), 243–253. https://doi. org/10.1007/BF00286150. Kartavtseva IV. (2002). Karyosystematics of Wood and Field Mice (Rodentia: Muridae). Dal’nauka Press, Vladivostok. 144 pp. Kearney TC, Volleth M, Contrafatto G and Taylor PG. (2002). Systematic implications of chromosome GTG-band and bacula morphology for southern African Eptesicus and Pipistrellus and several other species of Vespertilioninae (Chiroptera: Vespertilio- nidae). Acta Chiropterologica, 4(1), 55–76. https:// doi.org/10.3161/001.004.0107. Koubinová D, Sreepoda K, Koubek P and Zima J. (2010). Karyotypic variation in rhinolophid and hopposid- erid bats (Chiroptera; Rhirolophidae, Hipposideri- dae). Acta Chiropterologica, 12, 393–400. https://doi. org/10.3161/150811010X537972. Kruskop SV. (2006). Towards the taxonomy of the Rus- sian Murina. Russian Journal of Theriology, 4(2), 135–140. https://doi.org/10.15298/rusjtheriol.04.2.01. Kruskop SV. (2012). Order Chiroptera. In: Pavlinov, I.Y. & Lissovsky, A.A. (Editors). The Mammals of Russia: A Taxonomic and Geographic Reference. KMK Scien- tific Press, Moscow. 604 pp. https://doi.org/10.5772/ intechopen.78767. Kruskop SV, Borisenko AV, Ivanova NV, Lim BK and Eger JL. (2012). Genetic diversity of northeast- ern Palaearctic bats as revealed by DNA barcodes. Acta Chiropterologica, 14(1), 1–14. https://doi. org/10.3161/150811012X654222. Matthey, R. 1973. The chromosome formulae of eutheri- an mammals. In Cytotaxonomy and Vertebrate Evo- lution, ed. A. B. Chiarelli and E. Capanna, 531–616. Academic Press: London/New York. McCracken GF, Westbrook JK, Brown VA, Eldridge M, Federico P and Kunz TH. (2012). Bats track and exploit changes in insect pest populations. PLoS ONE, 7(8), e43839. https://doi.org/10.1371/journal. pone.0043839. Peterson RL. & Nagorsen DW. (1975). Chromosome of fifteen species of bats (Chiroptera) form kerygad Rhodesia. Life Science Occasional Paper Royals Ontario Museum, 27, 1–14. Porter CA, Primus AW., Hoffmann FG and Baker RJ (2010). Karyology of five species of bats (Vespertil- iondae Hipposideridae, and Nycteridae) from Gabon with comments on the taxonomy of Glauconycteris museum of Texas Tech. University Occasion paper, 295. https://doi.org/10.5962/bhl.title.156992. Primes A, Harvey J, Guimondou S, Mboumba S, Ngan- gui R, Hoffmann F, Baker R and Porter CA. (2006). Karyology and chromosome evolution of some small mammals inhabiting the rainforest of the Rabi oil field, Gabon. Bulletin of the Biological Society of Washington, 12, 372–382. Puig-Montserrat X, Torre I, L´opez-Baucells A, Guerrieri E and Monti MM. (2015). Pest control service pro- vided by bats in Mediterranean rice paddies: link- ing agroecosystems structure to ecological functions. Mammalian Biology, 80(3), 237–245. https://doi. org/10.1016/j.mambio.2015.03.008. Rautenbach IL, Bronner GN, Schlitter DA. (1993). Kar- yotypic data and attendant systematic implications for the bats of Southern Africa. Koedoe, 36, 87–104. https://doi.org/10.4102/koedoe.v36i2.377. Riccucci M. & Lanza B. (2014). Bats and insect pest con- trol: a review. Vespertilio, 17, 161–169. https://doi.org/10.1159/000106444 https://doi.org/10.1508/CYTOLOGIA.66.133 https://doi.org/10.1508/CYTOLOGIA.66.133 https://doi.org/10.3161/15081109ACC2017.19.1.001 https://doi.org/10.3161/15081109ACC2017.19.1.001 https://www.gamers.com.ng/map-of-enugu-state-nigeria/ https://www.gamers.com.ng/map-of-enugu-state-nigeria/ https://doi.org/10.1159/000131573 https://doi.org/10.1159/000131573 https://doi.org/10.1007/BF00286150 https://doi.org/10.1007/BF00286150 https://doi.org/10.3161/001.004.0107 https://doi.org/10.3161/001.004.0107 https://doi.org/10.3161/150811010X537972 https://doi.org/10.3161/150811010X537972 https://doi.org/10.15298/rusjtheriol.04.2.01 https://doi.org/10.5772/intechopen.78767 https://doi.org/10.5772/intechopen.78767 https://doi.org/10.3161/150811012X654222 https://doi.org/10.3161/150811012X654222 https://doi.org/10.1371/journal.pone.0043839 https://doi.org/10.1371/journal.pone.0043839 https://doi.org/10.5962/bhl.title.156992 https://doi.org/10.1016/j.mambio.2015.03.008 https://doi.org/10.1016/j.mambio.2015.03.008 https://doi.org/10.4102/koedoe.v36i2.377 14 Chinedu Innocent Ngene et al. Rickart EA, Mercier JA, Henny LR. (1999). Cytogeogra- phy of Philippine bats (Mammalia; Chiroptera). Pro- ceedings of the Biological Society of Washington, 112, 453–469. https://doi.org/10.5281/zenodo.13442161. Ruedas LA, Lee TE, Bickman J and Schlitter DA. (1990). Chromosomes of five species of vespertilionid bats from Africa. Journal of Mammalogy, 71(1), 94. htt- ps://doi.org/10.2307/1381324. Ruedi M, Csorba G, Lin LK and Chou CH. (2015). Molecular phylogeny and morphological revision of Myotis bats (Chiroptera: Vespertilionidae) from Tai- wan and adjacent China. Zootaxa, 3920(1), 301–342. https://doi.org/10.11646/zootaxa.3920.2.6. Schlitter DA, Rautenbach IL, Wohlhuter DA. (1980). Karyotpyes and morphometrics of two species of Scotophilus in South Africa (Mammalia: Vespertil- ionidae). Annals of the Transvaal Museum, 32, 231– 239. https://doi.org/10.2307/1381324. Simmons NB (2005). Order Chiroptera. In: Wilson, D. & Reeder, D.M. (Editors). Mammal Species of the World: A Taxonomic and Geographic Reference. Smithsonian Institution Press, Washington DC. Simmons NB. & Conway TM. (2003). Evolution of eco- logical diversity in bats. In: Kunz, T.H. & Fenton, M.B. (Editors). Bat Ecology. University of Chicago Press, Chicago, Illinois. Pp. 493–535. Sotero CG, Baker RJ, Volleth M. (2017). Chromosomal evolution in Chiroptera. Genes, 8(10), 272. https:// doi.org/10.3390/gene8100272. Sreepada K, Koubinová D, Konecny A, Koubek P, Rab P, Rábová M and Zima J. (2008). Karyotypes of three species of molossid bats (Molossidae, Chi- roptera) from India and West Africa. Folia Zoo- logica, 57, 347–357. https://www.ivb.cz/wp-content/ uploads/57_347-357.pdf. ISSN 0139-7893. Stevens RD. & Willig MR. (2002). Geographical ecology at the community level: perspectives on the diversity of New World bats. Ecology, 83, 545–560. https://doi. org/10.1890/0012-9658(2002)083[0545:GEATCL]2..0 .CO;2. Strelkov PP. (2006). The crisis of the polytypic species concept is illustrated by the genus Plecotus. Plecotus, 9, 3–7. Teeling EC, Dool S, Springer MS. (2012). Phylogenies, fossils and functional genes: the evolution of echo- location in bats. In: Gunnell, G. and Simmons, N. (Editors). Evolutionary History of Bats: Fossils, Molecules and Morphology. Cambridge University Press, Cambridge. Pp. 1–22. https://doi.org/10.1016/. tree.2006.01.001. Tiunov MP (2011). Distribution of the bats in the Rus- sian Far East. Proceedings of the Japan-Russia Coop- eration Symposium on the Conservation of the Eco- system. Okhotsk, Sapporo, pp. 359–369. https://doi. org/10.5772/intechopen.78767. Volleth M. & Heller KG (2012). Variations on a theme: karyotype comparison in Eurasian myotis species and implications for phylogeny. Vespertilio, 16, 329– 350. Volleth M, Heller KG, Fahr J. (2006). Phylogenetic rela- tionships of three “Nycticeiini” genera (Vespertilio- nidae, Chiroptera, Mammalia) as revealed by karyo- logical analysis. Mammalian Biology, 71(1), 1–12. https://doi.org/10.1016/j.mambio.2005.09.001. Volleth M, Heller KG, Pfeiffer RA and Hameister HA (2002). A comparison of zoo fish analysis in bats elucidates the phylogenetic relationships between Megachiroptera and five microchiroptera formulas. Chromosome Research, 10, 477–497. https://doi. org/10.1023/a:1020992330679. Volleth M, Son NT, Wu Y, Li Y, Yu W. et al. (2017). Com- parative chromosomal studies in Rhinolophus formos- ae and R. luctus from China and Vietnam: elevation of R. l. lanosus to species rank. Acta Chiropterolog- ica, 19(1), 41–50. https://doi.org/10.3161/15081109A CC2017.19.1.003. Wang LF, Walker PJ, Poon LL. (2011). Mass extinctions, biodiversity, and mitochondrial function: are bats “special” as reservoirs for emerging viruses? Cur- rent Opinion in Virology, 1(6), 649–657. https://doi. org/10.1016/j.coviro.2011.10.013. Wilson DE. & Reeder DM. (2005). Mammal Species of the World: A Taxonomic and Geographic Reference. 3rd Edition. Johns Hopkins University Press, Balti- more. https://doi.org/10.1644/06-MAMM-R-422.1. https://doi.org/10.5281/zenodo.13442161 https://doi.org/10.2307/1381324 https://doi.org/10.2307/1381324 https://doi.org/10.11646/zootaxa.3920.2.6 https://doi.org/10.2307/1381324 https://doi.org/10.3390/gene8100272 https://doi.org/10.3390/gene8100272 https://www.ivb.cz/wp-content/uploads/57_347-357.pdf https://www.ivb.cz/wp-content/uploads/57_347-357.pdf https://doi.org/10.1890/0012-9658(2002)083[0545:GEATCL]2..0.CO;2 https://doi.org/10.1890/0012-9658(2002)083[0545:GEATCL]2..0.CO;2 https://doi.org/10.1890/0012-9658(2002)083[0545:GEATCL]2..0.CO;2 https://doi.org/10.1016/.tree.2006.01.001 https://doi.org/10.1016/.tree.2006.01.001 https://doi.org/10.5772/intechopen.78767 https://doi.org/10.5772/intechopen.78767 https://doi.org/10.1016/j.mambio.2005.09.001 https://doi.org/10.1023/a:1020992330679 https://doi.org/10.1023/a:1020992330679 https://doi.org/10.3161/15081109ACC2017.19.1.003 https://doi.org/10.3161/15081109ACC2017.19.1.003 https://doi.org/10.1016/j.coviro.2011.10.013 https://doi.org/10.1016/j.coviro.2011.10.013 https://doi.org/10.1644/06-MAMM-R-422.1 15Genomic portraits: karyotyping of some Nigerian bat species Plate 1A . Mitotic metaphase chromosome of Epomophorus wahlbergi;Sex. Female. Plate 1B. The karyotype of Epomophorus wahlbergi. Plate 1C. A diagram of Epomophorus wahlbergi. 16 Chinedu Innocent Ngene et al. Plate 2B. The karyotype of Epomophorus gambianus. Plate 2A. Mitotic metaphase chromosome of Epomophorus gambi- anus; Sex. Female. Plate 2C. A diagram of Epomophorus gambianus. 17Genomic portraits: karyotyping of some Nigerian bat species Plate 3A. Mitotic metaphase chromosome of Microteropus pusillus; Sex. Female. Plate 3B. The karyotype of Microteropus pusillus. Plate 3C. A diagram of Microteropus pusillus. 18 Chinedu Innocent Ngene et al. Plate 4F. A diagram of Nycteris major; Sex. Female. Plate 4A. Mitotic metaphase chromosome of Nycteris major; Sex. Male. Plate 4B. Mitotic metaphase chromosome of Nycteris major; Sex. Female. Plate 4C. The karyotype of Nycteris major; Sex. Male. Plate 4D. The karyotype of Nycteris major; Sex. Female. Plate 4E. A diagram of Nycteris major; Sex. Male. 19Genomic portraits: karyotyping of some Nigerian bat species Plate 5B. The karyotype of Nycteris grandis; Sex. female. Plate 5A. Mitotic metaphase chromosome of Nycteris grandis; Sex. Female. Plate 5C. A diagram of Nycteris grandis. 20 Chinedu Innocent Ngene et al. Plate 6B. The karyotype of Nycteris arge. Plate 6C. A diagram of Nyceris arge. Plate 6A. Mitotic metaphase chromosome of Nycteris arge; Sex. Female. 21Genomic portraits: karyotyping of some Nigerian bat species Plate 7A. Mitotic metaphase chromosome of Scotophilus diaganii; Sex. Male. Plate 7C. A diagram of Sctotophilus diaganii. Plate 7B. The karyotype for Scotophilus diaganii. 22 Chinedu Innocent Ngene et al. Pate 8B. The karyotype for Scotophilus leucogaster. Plate 8A. Mitotic metaphase chromosome of Scotophilus leu- cogaster; Sex. Female. Plate 8C. A diagram of Scotophilus leucogaster. 23Genomic portraits: karyotyping of some Nigerian bat species Material 1. Ideogram of the karyotype of Epomophorus wahlbergi showing. (A) length variations (xxy shows sex chromosome of the male bat) and (B) centromeric locations. A) B) Material 2. Ideogram of the karyotype of Epomophorus gambianus showing. (A) length variations (xx shows sex chromosome of the female bat) and (B) centromeric locations. A) B) Material 3. Ideogram of the karyotype of Microteropus pusillus showing. (A) length variations (xx shows sex chromosome of the female bat) and (B) centromeric locations. A) B) APPENDIX 24 Chinedu Innocent Ngene et al. Material 4. Ideogram of the karyotype of Nycteris major showing. (A) length variations (xy shows sex chromosome of the male bat) and (B) centromeric locations. A) B) Material 5. Ideogram of the karyotype of Nycteris grandis showing. (A) length variations (xx shows sex chromosome of the female bat) and (B) centromeric locations. A) B) Material 6. Ideogram of the karyotype of Nycteris sp. showing. (a) length variations (xx shows sex chromosome of the female bat) and (b) centromeric locations. A) B) 25Genomic portraits: karyotyping of some Nigerian bat species Material 7. Ideogram of the karyotype of Nycteris arge showing. (A) length variations (xx shows sex chromosome of the female bat) and (B) centromeric locations. A) B) A) B) Material 8. Ideogram of the karyotype of Scotophilus diaganii showing. (A) length variations (xy shows sex chromosome of the male bat) and (B) centromeric locations. A) B) Material 9: Ideogram of the karyotype of Scotophilus lecuogaster showing: (A) length variations (xy shows sex chromosome of the male bat) and (B) centromeric locations. 26 Chinedu Innocent Ngene et al. Material 10. Giemsa Stain Preparation. 0.5g of Giemsa powder was dissolved in 33ml glycerol and kept in an Erlmyer bottle in a dark compartment overnight. The next day, it was heated in a water bath set at 60°C for 2 hours and allowed to cool, after which 33 ml of methanol was added and thoroughly mixed. This solution was then stored in an amber-coloured bottle as the stock Giemsa stain. 6% of the stock Giemsa stain was diluted as described below: 3 ml of the Giemsa stain, was diluted to 50 ml in Phosphate buffer, P.H. 6.8. The phosphate buffer was prepared fresh each time before usage by mixing 25 ml each of 9.464g of M/15 Na2HPO4 and 9.073g of M/15 KH2PO4, simultaneously. Material 11. Chromosome Nomenclature in Relation to Centrometric Indices (Abraham and Prasad, 1982). Nomenclature Notation R1 S/L R2 L/S I1 100s/c I2 100L/C Median M 1.00 1.00 50.00 50.00 Nearly median Nm 0.99–0.61 1.01–1.63 49.99–38.01 50.01–61.99 Nearly submedian nsm(-) 0.60–0.34 1.64–2.99 38.00–25.00 62.00–74.99 Sub-median SM 0.33 3.00 25.00 75.00 Nearly submedian nsm(+) 0.32–0.23 3.01–4.26 24.95–18.20 75.01–81.80 Nearly subterminal nst(-) 0.22–0.15 4.27–6.99 18.10–12.51 81.81–87.49 Subterminal ST. 0.14 7.00 12.50 87.50 Nearly subterminal nst(+) 0.13–0.07 7.01–14.38 12.49–5.01 87.51–94.99 Nearly terminal nt 0.06–0.01 14.39–19.99 5.00–0.01 95.00–99.99 Terminal T 0.00 0.00 0.00 100.00