SOME ASPECTS OF REPRODUCTIVE BIOLOGY AND MORPHOLOGICAL CHARACTERIZATION OF FROGS IN NORTH CENTRAL NIGERIA

Some aspects of reproductive biology and morphological characterization of frogs in north central, Nigeria was carried out. The aim was to identify and document different frog species, in Benue, Nasarawa, and Plateau States. A total of 750 adult frogs were collected during the 2023 rainy season (July–September) from rivers, ponds, and wetlands using dip nets at different times of the day, using standardized methods. The frogs were identified based on morphological characteristics, and detailed records of capture sites and conditions were maintained. In the laboratory, seventeen external morphometric traits, including body weight, lengths, head and limb dimensions, eye and tympanum diameter, and digit counts, were measured. To ensure accuracy, each morphometric parameter was measured three times per frog, with averages recorded and sexes analyzed separately to assess sexual dimorphism. Reproductive maturity and gonadal development were examined through dissections of specimens from Benue, Nasarawa, and Plateau States. While external features such as tympanum size, vocal sacs, and nuptial pads aided initial sex identification. Data were analyzed using descriptive statistics. The results showed that Xenopus laevis was the most abundant (536; 71.47%), followed by H. rugulosus (163; 21.73%), P. adspersus (41; 5.47%), and H. occipitalis (10; 1.33%). Species distribution was highest in Benue (300; 40.00%) and lowest in Plateau (200; 26.67%). Habitat-specific analysis confirmed X. laevis dominance in all states, ranging from 61.67% to 80.00% occurrence. PCA revealed that in X. laevis, PC1 explained 66.7% (males) and 59.9% (females) of variation, while in H. rugulosus, PC1 accounted for 42.4% (males) and 31.7% (females). Statistical analyses showed significant differences (p