Kryptoglanis shajii

Vincent and Thomas 2011

Kryptoglanis shajii
Kryptoglanis. Photograph by Ralf Britz


Species account reviewed by Ralf Britz.






Holotype: ZSI/WGRS/V/2121 59.1mm SL. Paratypes: ZMCC F 0102 35.0mm SL, ZMCC F 0103 54.4mm SL, ZMCC F 0105 35.5mm SL, ZSI/WGRS/V/2121 49.5mm SL [ex ZMCC F 0106].


Type locality: a water well at Aloor Village, Thrissur District, Kerala, India, depth of well 5.5 meters. 10°20.30'N, 76°18.37'E. Also known from: a well at Nellayi (Vylore) Village, Kerala, India (10o39’N, 76o27’E), which is 4km north of the type locality (Lundberg, Luckenbill, Subhash Babu and Ng 2014). A further site is at Perambra, Thrissur District (10o34’N, 76o30E), 2km from the type localilty. At the latter site many fish were observed in surface water channels having probably been washed out of the shallow laterite groundwater tunnels it normally inhabits (Binoy, Roshan and Rakesh 2012). The location of the single specimen used by Britz, Kakkassery and Raghavan (2014) was obtained from a public well near the town of Thrissur. The type locality of the clariid fish Horaglanis alikunhii is only 13km from the site described in Binoy, Roshan and Rakesh (2012).


The area in which this species (and also Horaglanis and Monopterus) is found is predominantly in laterite.


Britz, Kakkassery and Raghavan (2014) used traditional clearing and staining techniques on one individual to reveal the osteological detail. In an almost parallel study Lundberg, Luckenbill, Subhash Babu and Ng (2014) used high-resolution x-ray CT scanning (HRXCT) to examine the osteology of three specimens of K. shajii (specimen details given below). Britz et al. (2014) report on the cartilaginous skeleton, which is something Lundberg et al. (2014) were only able to do only within very confined limits and they also missed several structures. Both studies produced anatomically similar results and conclusions that suggested that this species is highly peculiar and unlike other members of the Siluriformes. In general the anatomical complexity is greatly reduced compared to other species. The conclusion of Vincent and Thomas (2011), that they could see no clear relationship with any family of siluriform fishes, was also supported by both studies. Lundberg, Luckenbill, Subhash Babu and Ng (2014:39) concluded that “…we do not find a simple, nested set of unambiguous synapomorphies that precisely resolve the phylogentic position of Kryptoglanis among catfishes.” Britz, Kakkassey and Raghavan (2014:205) resolved the issue: “Our analysis of the skeleton of Kryptoglanis shows that this unusual catfish cannot be assigned to any of the known catfish families. To highlight its highly unique anatomical structure we have decided to place it in its own family … Kryptoglanidae”. [For an interesting review of traditional and modern methods in fish morphological systematics, exemplified by these two studies, see Hilton, Schnell and Konstantinidis (2015)]. We are still no nearer in knowing which group is sister to Kryptoglanis shajii (though there is some similarity to the Siluridae) and it is probable that molecular data will need to be added to the morphological data in order to get closer to a resolution. [See Genetic resources below, but more will be needed than these small fragments of mitochondrial DNA].

Conservation Status


Museum Holdings

BMNH unnumbered 60.0mm SL (Britz, Kakkassery and Raghavan 2014), ANSP 192026 65.0mm SL, ANSP 192452 83mm SL, UMMZ 249918 51.0mm SL (Lundberg, Luckenbill, Subhash Babu and Ng 2014). Five fishes (out of many seen) were collected and preserved by Binoy, Roshan and Rakesh (2012) but their whereabouts was not published. Possibly five specimens in the collection of Moncey Vincent with details in Genetic Resources below.

Internet Resources

GenBank: HG937612.1 mt cytB specimen voucher M-CCI-KS1
GenBank: HG937611.1  mt cytB specimen voucher M-CCI-KF1
GenBank: FN691765.1 mt 16s rRNA  specimen voucher Moncey-CCI-NBFGR-C-KS5
GenBank: FN691764.1 mt 16s rRNA   specimen voucher Moncey-CCI-NBFGR-C-KS4
GenBank: HE801568.1 mt COI specimen voucher M-CCI-KS7
GenBank: HE801567.1 mt COI specimen voucher M-CCI-KS4


The osteology of Kryptoglanis shajii (from Lundberg, Luckenbill, Subhash Babu and Ng 2014)

Kerala State Groundwater Department

Key References

Vincent, M and Thomas, J Journal Article 2011 Kryptoglanis shajii, an enigmatic subterranean-spring catfish (Siluriformes, Incertae sedis) from Kerala, India
Binoy, V. V., Roshan, KS and Rakesh, VB Journal Article 2012 Occurence of Kryptoglanis shajii, an enigmatic subterranean-spring catfish (Siluriformes, incertae sedis) in channels of paddy field
Vincent, M. and Thomas, K.J. Book Section 2012 A preliminary survey on the subterranean piscine diversity in Thrissur District, Kerala, India
Lundberg, J.G., Luckenbill, K.R., Babu, K.K.S. and Ng, H.H. Journal Article 2014 A tomographic osteology of the taxonomically puzzling catfish Kryptoglanis shajii (Siluriformes, Siluroidei, incertae sedis): description and a first phylogentic interpretation
Britz, R., Kakkassery, F. and Raghavan, R. Journal Article 2014 Osteology of Kryptoglanis shajii, a stygobitic catfish (Teleostei: Siluriformes) from Peninsular India with a diagnosis of the new family Kryptoglanidae
De Grave, S., Arjun, C.P. and Raghavan, R. Journal Article 2018 The discovery of Euryrhynchidae (Crustacea: Decapoda) in India, with the description of a new genus and species