Subterranean Fishes of the World

Common name is Wader Goa

Country

Types

Syntypes: BMNH 1845.4.22.334–336, 1845.4.22.341–342

Distribution

Type locality: Java (?)

Known also from:

Gua Jomblang (or Djomblang), Gunung Sewu, Java, Indonesia (see Waltham et al. 1983, Willis et al. 1984)

Cijalu River, Cilacap Regency, Central Java (Nuryanto et al. 2016), Way Sindalapai River, Liwa Botanical Garden, West Lampung (Juriani et al. 2020)

Yawa Island (Doi 1997)

Systematics

Originally placed in the genus Barbus (Gunther 1868), and later moved to Puntius (Weber and De Beaufort 1916), a revision in 1993 placed it firmly in the genus Barbodes (Kottelat et al. 1993). A member od the subfamily Smiliogastrinae.

Biological Notes

Barbus microps was described by Günther (1868) and said to be closely allied to Barbus maculatus but with much smaller eyes. This species was from “Java (?)”. Jacobson (1912) reported on a visit to Java in February and March of 1911 and entitled his article “Iets over blinde visschen” which translates as “About blind fishes”. Specimens he collected were examined by Weber and DeBeaufort (1916) who decided that they were the same as Günther’s microps but they placed this species in the genus Puntius. The provenance of these specimens is given as “Java (subterraneous river in cave Djomblang near Gunung Sewu in Djocja !)”. They make the very significant remark that “some of the specimens from the above named cave, collected by Mr. E. Jacobson, have lost one or both eyes, probably through mutilation by crustacea”. Thines (1955:56-57, 1969:88) includes this species as one of his “poissons cavernicoles” but adds no further information.

In more recent times British cavers have explored many caves in the Gunung Sewu area of Java (see Waltham et al. (1983) for details of the area). In the same cave as that mentioned by Weber and DeBeaufort (1916), Gua Djomblang, Willis, Boothroyd and Briggs (1984) discovered and collected a number of small light coloured fishes. These were sent to the Natural History Museum in London where Keith Banister identified them as Barbus microps which he described as “quite widespread”. Some of the fishes have reduced eyes, some asymmetrically. Maurice Kottelat has examined these same specimens and is of the opinion that they are actually Puntius binotatus (pers. comm. 1998). The specimens are retained in the collection of Maurice Kottelat (accession number CMK 15108). It is possible that this is an incipient troglobitic population. Kottelat et al. (1993) placed microps in the genus Barbodes.

Tan and Husana (2021:309), in their description of Barbodes pyrpholeos, mention B. microps as follows: "Amongst the Sundaic populations of Barbodes, there is one cave-dwelling (troglobitic) species known from Java — B. microps. This poorly known species was described by Günther (1868) from the Gunung Sewu cave system, Central Java (according to Weber and de Beaufort 1916:186). Barbodes microps apparently exhibits a complete lack of pigmentation (see Kottelat et al. 1993:plate 16) and a variation in eye size and eye presence (eyes absent in some individuals). Haryono (2006) reported on the morphometry and meristics of 10 specimens of B. microps, and demonstrated morphometric differences between B. microps and B. binotatus (based on individuals from Sumatra, Kalimantan, and Java).

Doi (1997) says: " Puntius microps, distributed on Yawa Island, is similar to [Poropuntius speleops]. Dwelling in a cave, skin covers eyes as it grows."

In tentative conclusion we can probably say the following about this species: It is known from at least three epigean locations and at least one hygean location. Strictly, therefore, it is at most a troglophile and not a troglobite. In Gua Jomblang are found individuals that are generally lightly pigmented and have eyes which are smaller than other species and often asymetrical. These are characteristic of fishes in early troglomorphy. It is at least possible that the Gua Jomblang fishes are isolated from epigean fishes (if they exist in the area of the cave) and form a troglobitic population. Further studies are needed to confirm or refute this possibilty. If confirmed it may be desireable to consider the cave population as a separate species.

Museum Holdings

As above plus: CMK 15108