Homalictus terminalis, Dorey & Schwarz & Stevens, 2019

Dorey, James B., Schwarz, Michael P. & Stevens, Mark I., 2019, Review of the bee genus Homalictus Cockerell (Hymenoptera: Halictidae) from Fiji with description of nine new species, Zootaxa 4674 (1), pp. 1-46 : 37-40

Homalictus terminalis sp. nov.

( Figs 25–26 )

Material examined. Holotype ♂: 17FJ48 (SAMA 32-036147), Mt. Batilamu , Fiji, -17.68656, 177.54394, JB Do- rey, OK Davies, 27.4.2018, 1,118 m asl, 9:50 AM, RP17OKD0030, sweep netting area around the hut, long grasses and weeds (0.5-2 m high) with minimal flowers. Mostly roosting bees.

Allotype ♀: 17FJ43 (SAMA 32-036148), Mt. Batilamu , Fiji, -17.68656, 177.54394, 1,118 m, sweep netting, JB Dorey, OK Davies, 24.7.17, across the area around the hut, long grasses and weeds (0.5-2 m high) with minimal flowers. Mostly roosting bees.

Paratypes 2 ♀: 17FJ44 (SAMA 32-036149) & 17FJ41 (SAMA 32-036150), 27/4/17, 9:50 AM, 1,118 m asl, - 17.68656, 177.54394, JB Dorey & OK Davies, Mt. Batilamu , across the area around the hut, long grasses and weeds (0.5-2 m high) with minimal flowers. Mostly roosting bees .

Other material examined. 2 ♀: 17FJ50 and 17FJ68, 27/4/17, 9:50 AM, 1,118 m asl, -17.68656, 177.54394, JB Dorey & OK Davies, Mt. Batilamu , across the area around the hut, long grasses and weeds (0.5–2 m high) with minimal flowers. Mostly roosting bees .

Diagnosis. Males: Labrum has two medial projections and can be distinguished from males of H. nadarivatu by a lack of many vertical striae on the frons. Dorsal subapical crest of gonocoxite poorly developed and gonostylus laterally flattened ( Fig. 25e ).

Females: In combination: Bee is mostly green, supraclypeal area is mostly moderately colliculate, scape extends above head and sculpturing on anterior of scutum colliculate but not lineolate.

Description. Males: Measurements: UID 0.7 mm. LID 0.67 mm. AOD 0.26 mm. IAD 0.1 mm. OAD 0.44 mm. IOD 0.17 mm. OOD 0.2 mm. GW 0.24 mm. EW 0.4 mm. BL: 4.99 mm ML 0.13 mm. SL 0.33 mm. FL 3.85 mm.

Colouration: Whole clypeus partly iridescent and golden green and metallic. Supraclypeal area, frons, paraocular area, scutellum and propodeum dorsally golden green and metallic. Scutum partly metallic orange and pink and golden green and metallic. Metasoma T1 is black or nearly so, T2 onwards is green, dark green along posterior edges.

Sculpturing: Paraocular area striae, colliculate along margin of compound eyes. Frons with many diagonal striae, lateral striae under ocelli. Supraclypeal area mostly moderately colliculate, medial area finely colliculate. Clypeus finely colliculate. Vertex punctures very few, small and sparse. Scutum anteriorly finely colliculate and lineolate; medially finely colliculate; posteriorly moderately colliculate and lineolate. Scutellum punctation open and sparse. Propodeum; dorsally linear pattern and coarsely strigate-rugose; laterally finely colliculate and posteroventral and anterior striae curve towards each other and can meet; posteriorly finely and moderately colliculate and diagonal striae ventrally and proximally.

Morphology: Scape extends to above vertex. Interantennal distance about equal to diameter of socket. Labrum simple. Clypeus not depressed medially. Area posterior of vertex with strong and close striae. Posterior margin of Scutum shape mostly straight. Gonostylus well developed and flattened laterally, dorsoapical crest of gonocoxite weak. Fovea along anterior and proximal margin of eye absent.

Females: Measurements: UID 0.6–0.87 mm. LID 0.57–0.84 mm. AOD 0.2–0.3 mm. IAD 0.09–0.1 mm. OAD 0.32–0.49 mm. IOD 0.17–0.21 mm. OOD 0.16–0.25 mm. GW 0.1–0.32 mm. EW 0.11–0.38 mm. BL 4.51–5.56 mm. ML 0.11–0.16 mm. SL 0.25–0.39 mm. FL 3.34–4.18 mm.

Colouration: Clypeus anteriorly black; posteriorly golden green and metallic. Whole clypeus partly iridescent. Supraclypeal area, frons and paraocular area golden green and metallic or golden. Scutum partly metallic orange and pink and golden green and metallic. Scutellum golden green and metallic or partly metallic orange and pink. Propodeum dorsally golden green and metallic. Metasoma black, dark green or green, dark green along posterior edges.

Sculpturing: Paraocular area with some horizontal striae laterally and longitudinal striae, colliculate along margin of compound eyes. Frons mostly longitudinal striae. Supraclypeal area mostly moderately colliculate, medial area finely colliculate, rarely finely colliculate anteriorly. Clypeus finely colliculate. Vertex punctures minute open, fine and close. Scutum anteriorly moderately fine colliculate; medially and posteriorly finely colliculate or moderately fine colliculate. Scutellum punctation close and open. Propodeum; dorsally linear pattern, strong striae, weak medial anterior groove and coarsely strigate-rugose; laterally finely colliculate, ventral and anterior striae curve towards each other and can meet, some striae anteriorly and dorsally and some striae ventrally; posteriorly finely colliculate, moderately fine colliculate, transverse striae medially, transverse striae ventrally and proximally and striae originating ventrally and medially almost forms circles with dorsal striae. Pygidial plate with close minute punctures medially.

Morphology: Scape extends to above vertex. Interantennal distance about equal to diameter of socket. Labrum has two medial projections parallel from one another. Clypeus not depressed medially. Area posterior of vertex with strong and close striae. Posterior margin of Scutum shape mostly straight.

Comments. Given the very limited geographical and elevational distribution of H. terminalis it is likely to be threatened by climate warming in the future.

Distribution. Homalictus terminalis has only been sampled on Mt. Batilamu on the largest island of Viti Levu ( Fig. 26 ). Collections of H. terminalis sp. nov. have only been made between 1,100 m asl and 1,118 m asl; the summit of Mt. Batilamu is 1,195 m asl.

Etymology. Homalictus terminalis has only been found within 95 m of the maximum elevation available to it. The Latin noun terminalis means limit or boundary indicating the upper elevational and thermal limit that H. terminalis inhabits and could ultimately result in its extinction with global climate warming.

Figures

FIGURE 25. Homalictus terminalis sp. nov. male (a) dorsal habitus, (b) lateral habitus, (c) dorso posterior, (d) anteriorly frontal face and (e) ventral genitalia. Female (f) dorsal habitus, (g) lateral habitus, (h) dorso posterior, (i) anteriorly frontal face and (j) pygidial plate.

FIGURE 26. Collection map of Homalictus terminalis sp. nov. from specimens with identity confirmed by mtDNA COI gene. Sample size is 10.