Xylocopa coronata Smith 1860: 135

Mawdsley, Jonathan R., 2020, Notes on the taxonomy and distribution of Xylocopa coronata Smith, 1860, a large carpenter bee from Maluku, Indonesia (Insecta: Hymenoptera: Apidae), Insecta Mundi 2020 (799), pp. 1-5 : 2-5

Xylocopa coronata Smith 1860: 135

Fig. 1–13 .

Xylocopa coronata Smith 1860: 135 ; type locality “Kaisaa” (= Kaioa , also spelled Kayoa, Maluku, Indonesia) .

Holotype. Female, labeled “Kaisaa” and “ X. coronata Sm. , ‘Malay Arch’, F. Sm. coll.” found by the author in collection of the National Museum of Natural History, Smithsonian Institution, to be returned to the Frederick Smith Collection, Oxford University Museum, Fig. 1–4 .

Synonyms. Xylocopa combinata Ritsema (1876: 181) , type locality “Obi-eilanden” (= Obi, Maluku, Indonesia); synonymy by Lieftinck (1956: 63). Xylocopa coronata combinata Ritsema , combination proposed by Lieftinck (1956: 63).

Known distribution. Xylocopa coronata coronata Smith : Indonesia: Bacan: Wajaua, Labuha, and unspecified localities; Halmahera: Akilamo, Atjengo, Dodinga, Galelo, Goa, Kau, Tolewang, and unspecified localities in North, South, and Southeast Halmahera; Kai; Kaioa; Obi: Kasowari and unspecified localities; Ternate: Bukunora and unspecified localities; Tidore ( Lieftinck 1956: 62). The Kai locality given by Lieftinck (1956: 62) based on old specimens in the F. Smith collection requires confirmation, given the significant geographic distance between Kai or Kei and the other localities reported here for this species. Xylocopa coronata combinata Ritsema : Indonesia: Obi: Laiwui and unspecified localities ( Lieftinck 1956: 63).

Additional material examined. X. coronata coronata : Indonesia: Bacan Island , Kampung Wayamiga, 27–31 July 1981, A. C. Messer (1 female) ; “S. Batjan” with no further locality information, VI–VII.1953, A. M. R. Wegner (1 female, 1 male). Halmahera Island , Jailolo District, Isthmus of Dodinga, 29 January 1981, A. C. Messer and P. M. Taylor (1 female) ; Jailolo District , Kampung Pasir Putih, 0°53 ′ N, 127°41 ′ E, 1–14 January 1981, A. C. Messer and P. M. Taylor (11 females) ; same data except 15–31 January 1981 (2 females) ; same data except 1–14 February 1981 (3 females and 1 male) ; same data except December 1980 (1 female), same data except 1–14 May 1981 (2 females) ; same data except 15–31 July 1981, P. M. Taylor (1 female) ; same data except no date of collection (1 female) ; Kao District , Kao River Basin , Air Kanan, Kampung Tuguls, 1–14 March 1981, A. C. Messer and P. M. Taylor (1 female) ; Kao District , Kampung Kao, 19 March 1981, A. C. Messer and P. M. Taylor (1 female) ; Tobelo District , Kampung Rupo, 11 April 1981, A. C. Messer and P. M. Taylor (1 female). Ternate Island, T. Barbour (1 female). Tidore Island, Kampung Guaepaji, 5–10 July 1981, A. C. Messer (3 females) ; same data except 6–7 July 1981 (8 females). X. coronata combinata : Indonesia: Obi, NW Obi, Laiwui, 0–200 m, IX–X.1953, A. M. R. Wegner (2 females) ; same data except IX.1953 (1 female). All specimens in USNM collection .

Notes on type material of X. coronata . This species was originally described by Frederick Smith from a single female specimen collected at “Kaisaa” by Alfred Russel Wallace during his travels in the Malay Archipelago ( Smith 1860, 1874; see also Lieftinck 1956: 62, who notes that the original description was based on a single specimen). According to the detailed chronicle of Wallace’s travels published by Baker (2001), the locality “Kaisaa” corresponds to modern-day Kaioa or Kayoa, an island in the Maluku Archipelago of Indonesia. In preparation for his revision of the species of Xylocopa from the Maluku Archipelago, Lieftinck (1956: 62) was unable to locate any specimens in the Smith collection or other institutional collections which were specifically labeled “Kaisaa,” and material from “Kaisaa” is not listed among the numerous specimens of X. coronata that were examined by Lieftinck (1956: 62). Instead, Lieftinck (1956: 62) designated a female specimen collected at “Kai” as a lectotype for X. coronata . Kai or Kei is an altogether different island group within the Maluku Archipelago which is located approximately 872 km from Kaioa (shortest distance according to Google Maps 2020). While examining the collection of specimens of X. coronata in the National Museum of Natural History, Smithsonian Institution, I discovered a female with a smaller handwritten label stating it was collected at “Kaisaa” and a larger handwritten label indicating that it was from the F. Smith collection ( Fig. 1–4 ). The specimen corresponds closely with the description of the unique holotype provided by Smith (1860: 135) as well as the redescription of the holotype given by Smith (1874: 279–280) in his monographic revision of the genus Xylocopa . The accompanying larger handwritten label is similar in style and content to labels reported from the F. Smith collection by Lieftinck (1956: 62), while the handwriting on the smaller label is similar to that of Alfred Russel Wallace in the examples published by Baker (2001) and in additional examples of original Wallace labels studied by Mawdsley (2006). This specimen had been sent by staff of the Oxford University Museum of Natural History to the late Paul D. Hurd, Jr. of the Smithsonian Institution in preparation for his comprehensive monograph reclassification of the genus Xylocopa ( Hurd and Moure 1963) . Based on the evidence available, this specimen appears to be the original holotype specimen on which Smith’s description of the species was based.

Notes on geographic variation and subspecies. Lieftinck (1956) placed X. combinata Ritsema 1876 as a subspecies of X. coronata based on examination of pinned specimens, which included large series of specimens of both taxa, the original syntypic series of X. combinata , and multiple specimens of X. coronata which had been authoritatively identified by F. Smith. The principal difference between the two forms is in the coloration of the pubescence on the dorsal mesosoma in females. In certain populations on the island of Obi, particularly in the northwestern portion of the island, females have a broad band of yellow pubescence across the posterior portion of the mesosoma ( Fig. 8, 12 ) which is otherwise black in females from elsewhere in the Maluku Archipelago ( Fig. 1 , 5–7, 11 , 13 ). This color difference is very consistent in the limited material that I have examined, which suggests a possibility that two separate species may be involved. However, Lieftinck (1956: 64) notes that specimens with small amounts of yellow pubescence or individual yellow hairs on the base of the mesosoma occur at sites elsewhere in the species range, including the island of Bacan and West Obi. Further studies of morphology, species biology, and molecular systematics will be needed to determine the status of the populations on the island of Obi. For the time being, I prefer to follow Lieftinck (1956) in recognizing two separate subspecies, which can be separated readily by the differences in dorsal coloration of females.

In my own examination of specimens of X. coronata from the USNM collection, I noticed that the wing iridescence in female specimens of this species also exhibits geographic variation. In female specimens identified as X. coronata combinata from northwest Obi, the wings are iridescent blue-violet or blue-green, with strong blue iridescence predominating ( Fig. 8 ). Female specimens identified as X. coronata coronata from Tidore, Ternate, and Kaioa have wing iridescence that is coppery or coppery-violet in color ( Fig. 1 , 7 ), while females identified as X. coronata coronata from Halmahera and Bacan have wing iridescence that is purplish-blue with strong purple iridescence predominating ( Fig. 5, 6 ). Further study of additional specimens is needed to determine the exact geographic distribution of these various color variants. The color of wing iridescence is frequently used as a diagnostic character to separate taxa at the species level in other lineages of Xylocopa (see, for example, illustrations and discussion in Mawdsley 2017a, 2017b), and thus these different forms clearly merit further investigation in order to determine whether multiple valid species-level taxa are present. However, it should also be noted that at least one other widespread species of Xylocopa exhibits infraspecific geographic variation in wing iridescence coloration: the Central and South American X. (Neoxylocopa) frontalis (Olivier) , in which different populations have violet, blue, blue-violet, greenish-blue, golden-green, or dark green wing iridescence, as discussed by Hurd (1978).

Figures

Figure 13. Map showing known distribution of Xylocopa coronata, with schematic illustrations of the dorsal coloration patterns in females from each locality.

Figures 1–4. Holotype female of Xylocopa coronata and accompanying labels.1) Dorsal view.2) Labels.3) Lateral view. 4) Oblique view.

Figures 5–12. Female and male specimens of Xylocopa coronata; all are X. coronata coronata except for the female of X. coronata combinatain Figures 8 and 12. 5) Dorsal habitus, female, Halmahera.6) Dorsal habitus, female, Bacan. 7) Dorsal habitus, female, Tidore. 8) Dorsal habitus, female, Obi. 9) Dorsal habitus, male, Bacan. 10) Lateral view, male, Bacan. 11) Lateral view, female, Tidore. 12) Lateral view, female, Obi.