Lepidiota spp.

Lepidiota spp. from Palau

Arrow (1939) described Lepidiota carolinensis Arrow, 1939 from an unstated number of males and females from two localities on Babelthuap and one locality on Peleliu (the two islands are at least 40 km apart). The general records were repeated by Blair (1940). Two further species from Palau, L. dybasi Gordon, 1979 ( Fig. 13 View FIGURES 13–14 ) and L. furtiva Gordon, 1979 ( Fig. 14 View FIGURES 13–14 ), were subsequently added and form “a closely knit group” (Cartwright & Gordon 1979). Cartwright & Gordon (1979) also recorded L. carolinensis from Guam (1275 km northeast of Palau), but without any collection data.

Arrow (1939) did not designate a holotype for L. carolinensis , and NHML holds five specimens, one female and four males. To stabilise the nomenclature, I here designate a lectotype; the remaining four specimens in NHML become paralectotypes.

Type series. Lectotype ♂ (here designated) ( Fig. 12 View FIGURE 12 ): Aedeagus dissected out and mounted on a card; Co-type [printed, circular, yellow edged] | Brit. Mus. 1939-282 [printed and last three digits handwritten] | Z. Ono Coll’r. [printed] | Airai [printed] | Palao Ils. [printed] IV-17-’36 [handwritten] | Caroline Islands [printed] | Lepidiota carolinensis co-type Arrow [handwritten by Arrow; Horn & Kahle (1935 –37, tafel VI, fig. 24] | LECTOTYPE Lepidiota carolinensis Arrow, 1939 Selected Allsopp 2024 [printed, red label]; in NHML.

Paralectotypes: 1♂, Co-type (circular, yellow edged) | Brit. Mus. 1939-282 [printed and last three digits handwritten] | Palao Ils. [printed] IV-17-’36 [handwritten] | Caroline Islands (printed) | Lepidiota carolinensis co-type Arrow [handwritten by Arrow] | PARALECTOTYPE Lepidiota carolinensis Arrow, 1939 Selected Allsopp 2024 [printed, blue label]; 1♀, Co-type [circular, yellow edged] | female sign [handwritten] | Brit. Mus. 1939-282 [printed and last three digits handwritten] | Z. Ono Coll’r . [printed] | Ngeremlengui [printed] IV-23-’36 [handwritten] | Palao Ils. [printed] | PARALECTOTYPE Lepidiota carolinensis Arrow, 1939 Selected Allsopp 2024 [printed, blue label]; 1 ♂, Caroline Islands [printed] | Brit. Mus. 1939-282 [printed and last three digits handwritten] | Palao Ils. [printed] | Galdok IV-8-’36 [handwritten] | Z. Ono Coll’r . [printed] | PARALECTOTYPE Lepidiota carolinensis Arrow, 1939 Selected Allsopp 2024 [printed, blue label]; 1♂, Caroline Islands [printed] | Brit. Mus. 1939-282 [printed and last three digits handwritten] | Peleliu Is. [printed] | IV-20-’36 [handwritten] | Y. Kondo Coll’r. [printed] | PARALECTOTYPE Lepidiota carolinensis Arrow, 1939 Selected Allsopp 2024 [printed, blue label] | Lepidiota dybasi Gordon, 1971 det. Allsopp 2024 [printed and handwritten]; all in NHML

Comments. The last-listed paralectotype has antennomere 7 flattened, elongate and leaf-like, as in Cartwright & Gordon (1979, fig. 24), hence is L. dybasi . This is consistent with L. dybasi occurring on Peleliu and L. carolinensis occurring on Babelthuap.

BPBM holds six specimens marked as paratypes ( Fig. 15 View FIGURE 15 ). Although coming from the same series as those designated above as lectotype and paralectotypes, none shows evidence of being seen by Arrow: he did not mention any specimens in BPBM, he did not use the term “ paratype ” in labelling the NHML series, and the paratype labels are distinctly different from those he used and in a different handwriting to his. Hence, I do not consider them as paralectotypes.

Comparison of the type series of both H. burmeisteri and L. carolinensis , and especially the shape of the parameres ( Figs 16, 19–21 View FIGURES 16–21 ), clearly show that the two represent the same species ( Holotrichia burmeisteri Brenske, 1892 = Lepidiota carolinensis Arrow, 1939 , new synonymy).

Lepidiota spp. , as the generic name implies, have on at least their dorsal surfaces small, rounded, white scales that are contained within their punctures ( Fig. 23 View FIGURES 22–23 ), whereas H. burmeisteri View in CoL has unmodified elongate setae ( Fig. 22 View FIGURES 22–23 ), as do L. dybasi View in CoL and L. furtiva View in CoL ( Figs 13–14 View FIGURES 13–14 ). Lepidiota spp. are placed in the Leucopholini ( Lacroix 2010; Allsopp & Schoolmeesters 2024), whereas each of the three Palauan species key to the Rhizotrogini ( Lacroix 2010, pp. 19–20).