Leptogomphus, Dow & Stokvis & Ngiam, 2017

Dow, Rory A., Stokvis, Frank & Ngiam, Robin W. J., 2017, Revision of the Genus Leptogomphus Selys in Borneo, including gene trees and a two marker molecular phylogeny (Odonata: Anisoptera: Gomphidae), Zootaxa 4358 (2), pp. 201-257 : 238

Leptogomphus sp. cf williamsoni Laidlaw, 1912

( Figs 1 , 3 , 27 , 35 , 45 , 51 , 77 , 87 , 129 )

Leptogomphus williamsoni Laidlaw 1912 ;—Dow 2012: 7, 10 (♀, Gunung Penrissen and Annah Rais, Sarawak) ;— ? Dow et al. 2013b: 19, Fig. 20 (larvae, Kubah NP, Sarawak) .

Leptogomphus species;—Dow et al. 2016: 11 (females and larvae from Gunung Penrissen discussed).

Material studied. Sarawak, Malaysia: 1 ♀ ( SAR 11_12_GOM59, used in illustrations), boulder stream, Borneo Highlands Resort, Gunung Penrissen, Kuching Division, 1.13641N, 110.21555E, 24 vii 2012, leg. R.A. Dow, in collection Dow; 1 ♀ ( RMNH.5008436; teneral), same location, 29 vi 2014, leg. R.A. Dow, in RMNH; 1 ♀, stream, 1.12157N, 110.22701E, same area, 26 vii 2012, leg, R.A. Dow, in collection Dow; 1 ♀, small high gradient forest stream on Mount Matang, Matang Range, Kuching Division, 1.59632N, 110.20949E, 2 vii 2017, leg. R.A. Dow, in collection Dow.

Remarks. Females of Leptogomphus collected on Gunung Penrissen and in the Matang Range but not associated with L. schieli resemble L. williamsoni , but are atypical in some respects, and may represent yet another species. The chief differences are in the head ( Figs 27 , 35 , 45 , 51 ), where the occipital horns are placed close together, and there is an approximately crescentic depression surrounding the tubercles behind the lateral ocelli except at the front. It was only possible to include one specimen of this form in the molecular analysis, and only COI was successfully amplified; the sample is distinct from the other L. williamsoni samples ( Figs 1 , 3 ), but with only one sample and one marker we do not regard this as providing definitive support for the notion that this is a separate species. This is especially so since L. williamsoni is rather variable in the COI marker (see the Remarks under that species). In the absence of the male and more molecular data, we have decided to leave the issue of the status of this form open, nor do we provide a complete description; we do however provide a full set of illustrations. If it should prove to be a separate species, the Leptogomphus larva from Kubah National Park reported in Dow et al. (2013b) as L. williamsoni probably belongs here, since Kubah is in the Matang Range, where one of the females was collected. A female from Annah Rais at the foot of Gunung Penrissen, previously in the possession of the first author, probably belongs here as well; the specimen was not available to us to check for this study. The measurements of the three non-teneral specimens available are: abdomen without appendages 34–35mm, Hw 29– 30mm.

Figures

FIGURE 3. Phylogenetic reconstruction for 30 specimens of Leptogomphus and three outgroup taxa using the combined COI+ITS dataset. The best Maximum Likelihood tree is shown, with posterior probabilities from the Bayesian Inference analysis also depicted on the branches. Bootstrap values and posterior probabilities are shown if less than 100 or 1.0 respectively. RMNH collection codes are shown for each specimen, as well as the sex of the specimen and an indication of where it was collected.

FIGURE 129. Distribution of L. williamsoni (black square) and L.sp.cf williamsoni (red triangle).

FIGURE1. COI gene tree for 29 specimensof Leptogomphusand three outgroup taxon.The best Maximum Likelihood tree is shown, with posterior probabilities from the Bayesian Inference analysis also depicted on the branches. Bootstrap values and posterior probabilities are shown if less than 100 or 1.0 respectively. RMNH collection codes are shown for each specimen, as well as the sex of the specimen and an indication of where it was collected.

FIGURES 24–27. Female head dorsal: (24) L pendleburyi SAR16_GOM8; (25) L. schieli paratype SAR15_GOM6; (26) L. williamsoni SAR13_14_GOM51; (27) L.sp. cf williamsoni SAR11_12_GOM59.

FIGURES 32–35. Female head dorsal detail; h—occipital horn; p—pit; s—occipital spur; t—tubercle: (32) L pendleburyi SAR16_GOM8; (33) L. schieli paratype SAR15_GOM6; (34) L. williamsoni SAR13_14_GOM51; (35) L. sp. cf williamsoni SAR11_12_GOM59.

FIGURES 42–45. Female head frontal: (42) L pendleburyi SAR16_GOM8; (43) L. schieli paratype SAR15_GOM6; (44) L. williamsoni SAR13_14_GOM51; (45) L.sp. cf williamsoni SAR11_12_GOM59.

FIGURES 46–51. Female head frontal detail; h—occipital horn; ot—occipital tube; t—tubercle; th—tubercle horn: (46) L. coomansi SAR11_12_GOM48; (47) L pendleburyi SAR16_GOM8; (48) L. schieli paratype SAR15_GOM6; (49) L. species SAR11_12_GOM33; (50) L. williamsoni SAR13_14_GOM51; (51) L.sp. cf williamsoni SAR11_12_GOM59.

FIGURES 74–77. Female synthorax dorsal: (74) L pendleburyi SAR16_GOM8; (75) L. schieli paratype SAR15_GOM6; (76) L. williamsoni SAR13_14_GOM51; (77) L.sp. cf williamsoni SAR11_12_GOM59.

FIGURES 84–87. Female synthorax lateral: (84) L pendleburyi SAR16_GOM8; (85) L. schieli paratype SAR15_GOM6; (86) L. williamsoni SAR13_14_GOM51, right hand side, flipped for consistency;(87) L. sp. cf williamsoni SAR11_12_GOM59.

FIGURES18–23.Female headdorsal:(18) L.coomansi SAR11_12_GOM48;(19)L.mariaeholotype;(20) L.sp.cf coomansi PomS260; (21) L. pasia holotype; (22) L.sii paratype SAR13_14_GOM44; (23) L. species SAR11_12_GOM33.