Trichocolletes pulcherrimus Michener

Batley, Michael, 2012, Revision of the Australian Bee Genus Trichocolletes Cockerell (Hymenoptera: Colletidae: Paracolletini), Records of the Australian Museum (Rec. Aust. Mus.) 64 (1), pp. 1-50: 33-34

publication ID

http://doi.org/ 10.3853/j.0067-1975.64.2012.1589

publication LSID

lsid:zoobank.org:pub:42F22568-9A99-4F96-A422-F020AA558F90

persistent identifier

http://treatment.plazi.org/id/E93C9B69-4641-5D4E-5DB0-FAF7FC767F1D

treatment provided by

Carolina

scientific name

Trichocolletes pulcherrimus Michener
status

 

Trichocolletes pulcherrimus Michener  

Figs 9 View Figs 5–9 , 22 View Figs 20–23 , 26 View Figs 24–27 , 111 View Figs 104–115

Trichocolletes (Callocolletes) pulcherrimus Michener, 1965, p. 265   .

Specimens examined. Holotype ♂, Narrogin, Western Australia, 1 Nov. 1935, WAM (65–727) and the following. Western Australia: ♀, Dumbleyung, 14 Nov. 1966, H. Udell, WAM (9007); 4♀, 75 km E Hyden, 24–27 Oct. 1985, T. F. Houston, on flowers of Gastrolobium spinosum, WAM   (8997–9000); 2♂, 61 km E Hyden, 14 Oct. 1979, T. F. Houston, on flowers of Burtonia hendersoni, WAM   (9001–02); ♀, Regans Ford Moore River , 11 Nov. 1976, S. M. Postmus, on Jacksonia   sp., WAM (9006); ♀, 10 S Perenjori, 1 Nov. 1958, E. F. Riek, ANIC; 3♀, 19 km ESE Southern Cross, 28 Oct.1978, T. F.Houston, on flowers of Gompholobium viscidulum, WAM   (9003–05).  

Diagnosis

Length 16–18 mm; eyes not hairy; metasoma orangebrown with indistinct metasomal bands; flagellum banded dorsally in both sexes. Male hind tibia strongly expanded, without spurs; apical segment of flagellum truncate, slightly expanded on one side; fore trochanter with large spine. Female scape and more than half clypeus orange-brown.

Remarks. Detailed descriptions can be found in Michener, 1965.

In 1965, Michener proposed division of the genus Trichocolletes   into two subgenera, with this species as the sole member of the subgenus Callocolletes   . At that time, the Colletidae   family was regarded as a primitive lineage, but molecular evidence now indicates that it is one of the more derived (Danforth et al., 2006) and that separation of Trichocolletes   from other Australian colletids occurred relatively early (Almeida and Danforth, 2009). However, the premise on which the subgenus was based remains unaltered. If the hind basitibial area of T. pulcherrimus   females is intermediate in nature between those found in the remaining Trichocolletes   species and those of other colletids, it might indicate that T. pulcherrimus   occupies a basal position within the genus.

The use of molecular evidence from fresh material to test this hypothesis was, unfortunately, not possible as attempts to recollect specimens were unsuccessful, but the increased number of species now available made possible reassessment of the morphological evidence. Although the male exhibits a number of striking modifications including the absence of hind tibial spurs, Michener (1965, 2007) chose to give greater weight to the hind basitibial area and details of wing venation.

The basitibial area of females is difficult to observe because of a dense cover of stiff setae. When the setae are removed, the contiguous depressions at the base of each seta form a coarsely areolate surface ( Fig. 22 View Figs 20–23 ). Interpretation of the resulting structure can be difficult. Frequently specimens are found with the setae worn down to the tops of the depressions making the actual surface difficult to detect and producing an apparent rim to the basitibial area. A second difficulty is that even when setae are removed cleanly, the edge of the basitibial area may be coarsely serrated where it intersects the depressions (as shown for T. brachytomus   n.sp. in Fig. 21 View Figs 20–23 ). It is unclear whether or not this state should be classified as carinate.

A better character to use may be the hind basitibial area of males. Comparison of the basitibial areas of males of eight species with those of conspecific females confirmed that the degree of elevation of the basal area from the surrounding surface of the tibia in males reflected that observed for the females after removal of the setae. Of the

T. maximus   T. brachytomus   n.sp.

T. pulcherrimus   T. lacaris   n.sp. 38 species for which males are known, five, T. brachytomus   n.sp., T. dives   , T. lacaris   n.sp., T. pulcherrimus   and T. tuberatus   n.sp., were found to have basitibial areas at least as well developed as in T. pulcherrimus   ( Fig. 26 View Figs 24–27 ).

The second criterion used by Michener (1965) was the ratio of the lengths of the pterostigma and prestigma. This measurement is difficult to make accurately and involves a degree of subjectivity. It was found ( Table 1, Fig. 28 View Fig ) that the ratio for T. pulcherrimus   lies in the middle of the range for all species. Using 10 specimens each of T. orientalis   n.sp. and T. venustus   , it was estimated that the standard deviation of the measurements was 0.1.

Trichocolletes pulcherrimus   males are unique in having a combination of unusual characters, but with the exception of the loss of the hind tibial spurs, similar characters occur separately or in other combinations in a number of species: projections are found on the fore trochanters of males of T. avialis   n.sp. and T. nitens   n.sp.; modified legs are found in T. aureotinctus   , T. avialis   n.sp., T. burnsi   , T. dives   , T. dowerinensis   , T. hackeri   and T. macrognathus   n.sp.; and modified flagella occur in T. dives   and T. gelasinus   n.sp.. These male characters are not correlated with the female characters discussed above and it is concluded that the evidence presently available does not support recognition of the subgenus Callocolletes   .

Distribution. Southwestern Australia (AW, MAL, SWA) ( Fig. 111 View Figs 104–115 ).

WAM

Western Australian Museum

T

Tavera, Department of Geology and Geophysics

ANIC

Australian National Insect Collection

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Hymenoptera

Family

Colletidae

Genus

Trichocolletes

Loc

Trichocolletes pulcherrimus Michener

Batley, Michael 2012
2012
Loc

Trichocolletes (Callocolletes) pulcherrimus

Michener, C 1965: 265
1965