Bombus (Pyrobombus) taiwanensis Williams, Sung, Lin & Lu, 2022

Williams, Paul H., Dorji, Phurpa, Ren, Zongxin, Xie, Zhenghua & Orr, Michael, 2022, Bumblebees of the hypnorum-complex world-wide including two new near-cryptic species (Hymenoptera: Apidae), European Journal of Taxonomy 847, pp. 46-72 : 56

Bombus (Pyrobombus) taiwanensis Williams, Sung, Lin & Lu, 2022

Figs 1‒4

[ Bombus sp. non descripta Chiu 1948: 71.]

[ Bombus (Pyrobombus) nr. hypnorum Starr, 1992: 149 .]

Bombus (Pyrobombus) taiwanensis Williams et al., 2022: 438 . Holotype by original designation: ♀, Mt Hehuan , Taiwan (TFRI). Examined.

Diagnosis

Female

Distinguished by: clypeus in the central area smooth and shining with only a few large punctures, mostly spaced by much more than their own widths; ocello-ocular area with the inner eye margin mostly shining with few small punctures and the few larger, medium punctures forming a single row parallel to the eye margin; front, middle and hind leg basitarsi all with the exoskeleton lighter brown than for the tibiae; hair predominantly black but with metasomal T4‒6 a dull sandy-brown or pale orange.

Male Distinguished by: front, middle and hind leg basitarsi all with the integument lighter brown than the tibiae; genitalia with the gonostylus inner anterior (basal) projection separated from the gonocoxa by less than the breadth of the recurved hook of the penis-valve head.

Material examined

Material sequenced or examined

CHINA – Taiwan • 1 ♀ (worker); Nantou Hsien , Tsuifeng [ Cuifeng ]; 24.1060° N, 121.1988° E; alt. 2300 m; 23‒25 Jun. 1983; K.S. Lin and C. Lin leg.; BOLD-1550A06-TWN ; PW • 1 ♂; Hualien Hsien, Tayuling ; 23.9767° N, 121.5206° E; alt. 2560 m; 9‒16 Jun. 1980; K.S. Lin and B.H. Chen leg.; BOLD- 1550A07-TWN ; PW .

Other material sequenced

GenBank: MZ831884 , MZ831885 , MZ831886 , MZ831887 , MZ831891 , MZ831892 .

Distribution

Endemic to the mountains of Taiwan, where it is extremely rare, at elevations of 2300‒3100 m ( Williams et al. 2022).

Figures

Fig. 1. MRBAYES estimate of phylogeny as a metric tree (outgroup B. alpinus (Linnaeus, 1758) not shown) from COI barcodes from GenBank and BOLD databases for the vagans-group and hypnorum- group, with additions from the authors for the hypnorum-group of bumblebees, filtered to remove duplicate and short sequences. Each sequence is labelled with: sequence length; a taxon name from the database; a code consisting of a sequence identifier from the project database and a specimen identifier from the online database; its country and (for larger countries) state or province). The scale bar is calibrated in substitutions per nucleotide site. Results of Bayesian Poisson-tree-process (PTP) models applied for assessing support for species’ gene coalescents by maximum likelihood are shown as PTP scores above the branches: scores approaching 1 and where branches change from blue to red indicates are where the most likely species’ gene coalescents are detected. Asterisks mark sequences used as informal proxies for the type specimens of each of the taxon names in Table 2.

Fig. 2. Distribution of barcoded samples of the hypnorum-complex and B. perplexus Cresson, 1863, with the interpretations as separate candidate species from Fig. 1 shown as different coloured spots as per the colour key on the left. Relief map with hill shading, polar projection (north pole shown as a star), the international boundaries and the Arctic Circle are shown as narrow grey lines, and the northern tree line shown as a broad grey line. Image created in ArcGIS using World_Shaded_Relief basemap (© 2014 Esri).

Figs 3–38. Simplified diagrams for the colour patterns of the hair on the dorsum for ♀♀ (left) and ♂♂ (right) of the Bombus species from Fig. 2. The dorsum is divided into regions, each of which shows only the predominant or most apparent colour for that region using a simplified colour palette (precise shades vary), with olive indicating a mixture of black and yellow hair, and grey indicating a mixture of black and white hair.