Congolian Long-Fingered Frog
Species Description: Hirschfeld, M., D.C. Blackburn, M. Burger, E. Greenbaum, A.-G. Zassi- Boulou, and M.-O. Rödel. 2015. Two new species of long-fingered frogs of the genus Cardioglossa (Anura: Arthroleptidae) from Central African rainforests. African Journal of Herpetology 64: 81–102.
Like all other Cardioglossa species, Cardioglossa congolia has a slim body, elongated legs, a long third finger in males, and a recognizable color pattern. Analysis of the mitochondrial 16S rRNA gene indicates that Cardioglossa congolia is within the Cardioglossa genus and forms a subclade with Cardioglossa escalerae, Cardioglossa gratiosa, Cardioglossa nigromaculata, Cardioglossa trifasciata, and Cardioglossa annulata. Cardioglossa congolia is distinguishable from most other species in the genus by its markings, as it lacks the hourglass pattern or three large black spots that most others in the genus have on their dorsum. Other Cardioglossa that also lack these patterns are Cardioglossa oreas, Cardioglossa manengouba, Cardioglossa pulchra, and Cardioglossa venusta. Cardioglossa congolia is distinguished from these species by its infratympanal line. Morphologically, Cardioglossa congolia is most similar to Cardioglossa gratiosa and Congolia annulata, but is differentiated by its lack of dark cross bars on its limbs. Cardioglossa congolia also differs from Cardioglossa gratiosa through its less noticeable infratympanal line. Cardioglossa congolia further differs from Cardioglossa annulata by the black spots on its belly, while Cardioglossa annulata has meandering light and dark coloring (Hirschfeld et al. 2015).
In life, the dorsum is a greyish brown with irregular black spots that extend to the dorsal areas of the limbs. Black spots ringed by white lines occur on the anterior areas of the front and hind limbs and the posterior surfaces of the upper arms and thighs. The throat is dark grey and the head has a dark mask outlined by a thin white line. The mask covers the tympanum and wraps posteriorly behind the arm and along the flanks to about mid-body, where it breaks into irregular spots. The ventral edge of the mask has a thicker white line that ends just ventral to the eye. A large black inguinal spot spreads through most of the posterolateral surface of the dorsum. The ventral surface has crisscrossed light grey lines around irregular dark spots. In preservative, the color pattern fades over time (Hirschfeld et al. 2015).
Body size and number and extent of hand spines varies slightly in males, with one paratype entirely lacking spines on the medial surface of the third finger of left hand. The size and number of black spots on the lateral and dorsal surfaces and the pattern of grey lines on the venter also vary slightly. Some specimens have patterned throats. The overall coloration can be slightly lighter than the coloration of the holotype. No females have been collected, so any sexual dimorphism is unknown (Hirschfeld et al. 2015).
Distribution and Habitat
Country distribution from AmphibiaWeb's database: Congo, the Democratic Republic of the
Life History, Abundance, Activity, and Special Behaviors
Analysis of the mitochondrial 16S rRNA gene indicates that Cardioglossa congolia is within the Cardioglossa genus and forms a subclade with Cardioglossa escalerae, Cardioglossa gratiosa, Cardioglossa nigromaculata, Cardioglossa trifasciata, and Cardioglossa annulata. Analysis of the mitochondrial 16S gene showed low or moderate divergence in DNA sequences between Cardioglossa Congolia and other closely related Congolia species (Hirschfeld et al. 2015).
The species epithet, “Congolia”, comes from the name of a biological sub-center of the Guinea-Congolian rainforest region where Cardioglossa congolia is found (Hirschfeld et al. 2015).
One of the three specimens was previously categorized as Cardioglossa gratiosa (Hirschfeld et al. 2015).
Hirschfeld M, Blackburn DC, Burger M, Greenbaum E, Zassi-Boulou A-G, and Rödel M-O (2015). ''Two new species of long-fingered frogs of the genus Cardioglossa (Anura: Arthroleptidae) from Central African rainforests.'' African Journal of Herpetology, 64(2), 81-102.
Originally submitted by: Sierra Raby (first posted 2016-11-30)
Edited by: Ann T. Chang (2016-12-06)
Species Account Citation: AmphibiaWeb 2016 Cardioglossa congolia: Congolian Long-Fingered Frog <https://amphibiaweb.org/species/8379> University of California, Berkeley, CA, USA. Accessed May 23, 2022.
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Citation: AmphibiaWeb. 2022. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 23 May 2022.
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