Romblonella opaca

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Romblonella opaca
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Crematogastrini
Genus: Romblonella
Species: R. opaca
Binomial name
Romblonella opaca
(Smith, F., 1861)

Romblonella opaca casent0178525 profile 1.jpg

Romblonella opaca casent0178525 dorsal 1.jpg

Specimen labels


Nothing is known about the biology of Romblonella opaca.


General and Buenavente (2015) - In dorsal view, first gastral tergite (abdominal tergite IV) punctulate but never longitudinally costulate. In full-face view, head subquadrate (CI =95); median clypeus wider than frontal lobe; mesosoma, in lateral view, entirely dark brown.

There are two species of Romblonella known from the Philippines. The following couplet can be used for determinations:

  • In dorsal view, first gastral tergite (abdominal tergite IV) longitudinally costulate with interstitial punctulae. In full-face view, head longer than broad (CI 84-89); median clypeus narrow, only as wide as frontal lobe; mesosoma, in lateral view, distinctly dark orange and brown . . . . . Romblonella coryae
  • In dorsal view, first gastral tergite (abdominal tergite IV) punctulate but never longitudinally costulate. In full-face view, head subquadrate (CI =95); median clypeus wider than frontal lobe; mesosoma, in lateral view, entirely dark brown . . . . . Romblonella opaca


Distribution based on Regional Taxon Lists

Indo-Australian Region: Indonesia (type locality), Philippines, Sulawesi.

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb




The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • opaca. Myrmica opaca Smith, F. 1861b: 47 (w.) INDONESIA (Sulawesi). Combination in Tetramorium: Emery, 1901g: 567; Donisthorpe, 1932c: 469; in Romblonella: Bolton, 1976: 294. Senior synonym of grandinodis: Bolton, 1976: 294.
  • grandinodis. Romblonella grandinodis Wheeler, W.M. 1935a: 7, fig. 2 (w.) PHILIPPINES. Junior synonym of opaca: Bolton, 1976: 294.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.



General and Buenavente (2015) - Lectotype: TL 5.13, HL 0.98, HW 0.93, CI 95, SL 0.55, SI 59, EL 0.19, EI 20, PW 0.65, ML 1.18, GL 1.08, HFL 0.75.

In full face view, posterior margin of head broadly concave; head subquadrate (CI = 95); sides of head gently converging anteriorly; eyes located laterally, slightly behind midlength of head; shallow antennal scrobe present; frontal carina long but about 1 eyelength short of posterior margin of head; antennal scapes short, exceeding posterior edge of eye by less than scape width of distal scape at distal margin; antennae with 12 segments and a 3-segmented club; mandibles triangular, with 6 robust teeth; palp formula 5:3; median clypeus with a median carina flanked by 2 pairs of lateral carinae; median clypeus wider than frontal lobe, posteriorly inserted between frontal lobes; anterior clypeal margin entire, without an isolated median seta; head reticulate with punctae in interstitial spaces; mandibles striate.

In lateral view, dorsal margin of mesosoma smoothly and slightly convex, without grooves or sutures; propodeal spines long and stout; petiole sessile, with anterodorsally directed angle over petiolar spiracle; petiole massive, larger and taller than postpetiole; anterior subpetiolar denticle present; spurs absent on meso- and metatibia.

In dorsal view, pronotum angulate; sides of promesonotum subparallel, propodeum noticeably narrower than promesonotum; propodeal spines divergent at bases but parallel in distal third of their length; mesosoma, petiole and postpetiole dorsally reticulate with interstitial punctulation; first gastral (= 4th abdominal) tergite punctulate.

Head and body with abundant short, blunt erect hairs about as long as distance between them; antennal scape with suberect hairs.

Body dark brown with lighter mandibles and antennae.

Type Material

The following notes on F. Smith type specimens have been provided by Barry Bolton (details):

Myrmica opaca

Holotype worker in Oxford University Museum of Natural History. Labelled “Tond.” (= Tondano, Sulawesi).

General and Buenavente (2015) - R. grandinodis syntype workers (MCZ Type 20977) [examined]; top worker specimen on double pin here designated as LECTOTYPE. The lower specimen and the collection (2 specimens) of the Smithsonian Institution are designated as PARALECTOTYPES (Ms. Eugenia Okonski kindly confirmed the existence of the last two specimens in the Smithsonian Institution, by sending DEMG images of the specimens and labels.). Labels: Romblon Is./ 5/6/24 / coll. L. Morato [not Marato, as in Wheeler, 1935 and subsequent publications]

University of the Philippines material of Romblonella grandinodis presents a couple of problems that might not be solvable. On a single pin with 2 mounted specimens, there are two legacy locality labels. The top tag, a typical label by Dr. J.W. Chapman, indicates “Camp, 1924/ Dumaguete, P.I./ coll. J.W. Chapman”. “Camp” presumably refers to Dr. Chapman’s favorite ant-collecting camp somewhere on the Dumaguete side of Mt. Cuernos de Negros, Negros Island. “P.I.” is an abbreviation for Philippine Islands, the American colonial-era term for the Philippines, now disused. There is also a determination label which reads “Romblonella grandinoda Wh.”[sic]. The problem arises from the other labels: “Cotype” on one side of yellow card and, on its flipside, a second locality label which reads “Romblon, P.I./ L. Morato coll.”; and a printed red card which reads “MCZ Co-Type” with the handwritten characters “Co- ”but no numbers and now pinned upside-down. How is one to interpret this perplexing situation of one double-pin with two locality labels indicating two different islands? Wheeler (1935) wrote that the type series was composed of 4 workers. The four specimens in the type series are accounted for: two specimens are in MCZ and two are in the Smithsonian Institution (DEMG, unpublished notes, E. Okonski, pers. comm.) We speculate that there were originally 5 workers in the collection by L. Morato. Wheeler returned one specimen of what would become the type series to Chapman before Wheeler wrote the genus description. And that, when Wheeler wrote his 1935 paper, he forgot about the returned specimen as part of the type series, hence he mentioned only 4 workers in the type series and as a consequence, there is a MCZ Co-Type label without a number. This label is now pinned upside-down, probably to indicate that it is no longer considered a real co-type. As regards the second specimen on the pin, it is highly unlikely that Chapman was so short of insect pins that he combined 2 separate collections on a pin. It is more likely that storage space, e.g. insect drawers, was so limited that he combined the 2 collections on a single pin. We emphasize that this is simply speculation to explain the curious situation of 2 legacy locality labels on a single pin. In addition, there is still the intractable problem of which locality label goes with which specimen.


  • Bolton, B. 1976. The ant tribe Tetramoriini (Hymenoptera: Formicidae). Constituent genera, review of smaller genera and revision of Triglyphothrix Forel. Bull. Br. Mus. (Nat. Hist.) Entomol. 34: 281-379 (page 294, Combination in Romblonella, and senior synonym of grandinodis)
  • Donisthorpe, H. 1932c. On the identity of Smith's types of Formicidae (Hymenoptera) collected by Alfred Russell Wallace in the Malay Archipelago, with descriptions of two new species. Ann. Mag. Nat. Hist. 10(10): 441-476 (page 469, Combination in Tetramorium)
  • Emery, C. 1901i. Formiciden von Celebes. Zool. Jahrb. Abt. Syst. Geogr. Biol. Tiere 14: 565-580 (page 567, Combination in Tetramorium)
  • General, D.E.M. & Buenavente, P.A.C. 2015. A second species of the ant genus Romblonella from the Philippines (Hymenoptera: Formicidae). Halteres, 6, 56-62.
  • Smith, F. 1861b. Catalogue of hymenopterous insects collected by Mr. A. R. Wallace in the islands of Ceram, Celebes, Ternate, and Gilolo. [part]. J. Proc. Linn. Soc. Lond. Zool. 6: 36-48 (page 47, worker described)