Labiobaetis xeniolus (Lugo-Ortiz & McCafferty, 1999)

Kaltenbach, Thomas, Vuataz, Laurent & Gattolliat, Jean-Luc, 2023, New species of Labiobaetis Novikova & Kluge from New Guinea (Ephemeroptera, Baetidae): a never-ending story of diversity, Alpine Entomology 7, pp. 83-134 : 83

2. Labiobaetis xeniolus (Lugo-Ortiz & McCafferty, 1999)

Pseudocloeon xeniolum : Lugo-Ortiz et al. 1999.

Remarks to morphology.

Larva. Based on the original description and the figures in Lugo-Ortiz et al. 1999, most of the diagnostic characters of group Labiobaetis petersorum are present. Exceptions are: the presence of dots on the flagellum; two additional distolateral tufts of setae on hypopharynx; stout setae on posterior apex of fore and middle legs; anal margin of the tergalii with both short and long setae. These characters remain unknown until complete re-examination of type material. Additionally, subapical setae are also not mentioned in the original description, but may have been overlooked. However, based on stacking videos, the fore legs of two paratypes have no subapical setae, other legs are not embedded in the slides ( Lugo-Ortiz et al. 1999: 20).

MOTUs (see discussion in Kaltenbach et al. 2020). We studied specimens with the same morphology as L. xeniolus , collected in different locations far away from the type locality of L. xeniolus (Fig. 38a, b ). The most important characters for the species assignment are: short, conical labial palp segment III; tergalii with remarkably strong development and pigmentation of tracheae; paraproct with poorly developed marginal spines. Based on COI sequences, we can distinguish seven different MOTUs ( L. cf. xeniolus A-G; Table 1 ; Fig. 39 ). Unfortunately, a sequence from the type locality of L. xeniolus or nearby is lacking. We remain prudent and denominate these specimens as "cf. Labiobaetis xeniolus ". Interestingly, these specimens have all characters of the group Labiobaetis petersorum , including subapical setae. This is pointing into the direction that L. xeniolus from the type locality equally might have all characters of the group Labiobaetis petersorum , incl. subapical setae.

Material examined.

Labiobaetis xeniolus . Paratypes. PAPUA NEW GUINEA • 2 larvae; Morobe Prov., Poverty Cr., Mt. Missim ; 1600 m; 18.ix.1983; J.T. and D.A. Polhemus; on slides; PERC0012578, PERC0012579; Purdue University .

Labiobaetis cf. xeniolus A. PAPUA NEW GUINEA • larva; Western Highlands Prov., Simbai, Kairong River; 05°14'50"S, 144°28'27"E; 1850 m; 02.iii.2007; leg. Kinibel; (PNG 139); on slide; GBIFCH00829891; MZL • larva; Enga Prov., Wapanamanda; 05°38'06"S, 143°55'20" E; 1500 m; 06.xii.2006; leg. M. Balke and Kinibel; ( PNG 128); on slide; GBIFCH00829892; MZL • larva; Madang Prov., Simbai area ; 05°12'42"S, 144°35'31"E; 1800-2400 m; 08.iii.2007; leg. Kinibel; (PNG 151); on slide; GBIFCH00975618; MZL .

Labiobaetis cf. xeniolus B. PAPUA NEW GUINEA • 2 larvae; Central Prov. , Tapini ; 08°20'31"S, 146°59'49"E; 870 m; 29.x.2007; leg. Kinibel; (PNG 161); in alcohol; GBIFCH00515640, GBIFCH00829889; MZL • 1 larva; Central Prov., Kokoda Trek; 09°14'20"S, 147°40'32"E; 1400 m; i.2008; leg. Posman; ( PNG 171); on slide; GBIFCH00829888; MZL .

Labiobaetis cf. xeniolus C. PAPUA NEW GUINEA • 16 larvae; Morobe Prov., Menyamya, Mt. Inji ; nr 07°14'49"S, 146°01'20"E; 1700 m; 14.xi.2006; leg. M. Balke and Kinibel; (PNG 96); 1 on slide; GBIFCH00763703; 15 in alcohol; GBIFCH00829886; MZL .

Labiobaetis cf. xeniolus D. PAPUA NEW GUINEA • 2 larvae; Western Highlands Prov., Kundum ; 05°16'06"S, 144°27'52"E; 1400 m; 03.iii.2007; leg. Kinibel; (PNG 142); 1 on slide; GBIFCH00975631; 1 in alcohol; GBIFCH00515635; MZL .

Labiobaetis cf. xeniolus E. PAPUA NEW GUINEA • 2 larvae; Central Prov. , Kokoda Trek; 09°01'57"S, 147°44'27"E; 1400 m; i.2008; leg. Posman; (PNG 172); 1 on slide; GBIFCH00975627; 1 in alcohol; GBIFCH00515638; MZL .

Labiobaetis cf. xeniolus F. PAPUA NEW GUINEA • 6 larvae; Madang Prov., Simbai area; 05°13'23"S, 144°37'17"E; 1200 m; 10.iii.2007; leg. Kinibel; (PNG 152); 2 on slides; GBIFCH00515634, GBIFCH00763704; 4 in alcohol; GBIFCH00975619, GBIFCH00975668, GBIFCH00829896; MZL • 2 larvae; Madang Prov., Simbai area ; 0 5°13'20"S, 144°37'37"E; 1200 m; 11.iii.2007; leg. Kinibel; ( PNG 153); on slides; GBIFCH00515637, GBIFCH00975630; MZL .

Labiobaetis cf. xeniolus G. PAPUA NEW GUINEA • 4 larvae; Central Prov. , Woitape; 08°31'35"S, 147°14'06"E; 1600 m; i.2008; leg. Posman; (PNG 165); 3 on slides; GBIFCH00592681, GBIFCH00975666, GBIFCH00829894; 1 in alcohol; GBIFCH00515627; MZL .

Figures

Figure 38. Distribution of species treated in this study: a. Species of group Labiobaetis petersorum and L. kokoda sp. nov.; b. MOTUs of group Labiobaetis petersorum, not described in this study.

Figure 39. Bayesian majority-rule consensus tree reconstructed from the CO 1 data set. Coloured vertical boxes indicate species delimitation hypothesis (MOTUs) according to the ASAP, PTP and GMYC methods. Tips are labelled according to Table 1. For each GMYC-based MOTU, the corresponding species name (where available) is provided, with newly described species specified in bold. Circles on branches indicate Bayesian posterior probabilities> 0.9.