Homalictus concavus, 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 : 21-24

Homalictus concavus sp. nov.

( Figs 13–14 )

Material examined. Holotype ♂: 17FJ170 ( SAMA 32 -036200), 13/4/17, 1:20 PM, 815 m asl, -16.81945, 179.93845, MI Stevens, Taveuni , edge of the bog from sweeping the tiny white flowers at edge of lake.

Allotype ♀: 17FJ177 (SAMA 32-036201), Taveuni , Fiji, -16.819650, 179.942050, JB Dorey, 14.04. 2017, 816 m asl, TV17-JD04, Taveuni, 100 m to edge of forest, wet ground, among stands of cabbage tree-like plants. Several larger plants (trees) with bottle brush-like red flowers. Only a few of these trees were flowering with this tree flowering the most profusely. This tree was 4–5 m high.

Paratypes 2 ♂: AFG006 (SAMA 32-036204) and AFG001 (SAMA 32-036205), 30/8/11, 11:55 AM, 703 m asl, -16.8287, -179.9810, SVC Groom; and 2 ♀, 17FJ182 (SAMA 32-036202), 14/4/17, 11:49 AM, 818 m asl, - 16.819267, -179.93862, JB Dorey, edge of the bog from sweeping the tiny white flowers at edge of lake. No bees were caught in the malaise or blue vein at this location; and 17FJ181 (SAMA 32-036203), 14/4/17, 10:47 AM, 816 m asl, -16.81965, -179. 94205, JB Dorey, Taveuni, 100 m from edge of forest, wet ground, among stands of cabbage tree-like plants. Several larger plants (trees) with bottle brush-like red flowers. Only a few of these trees were flowering with this tree flowering the most profusely. This tree was 4–5 m high.

Other material examined. 1 ♀: 17FJ171, 13/4/17, 1:20 PM, 815 m asl, -16.81945, 179.93845, MI Stevens, Taveuni, edge of the bog from sweeping the tiny white flowers at edge of lake.

Diagnosis. Males: Supraclypeal area mostly finely colliculate ( Fig. 1 f–g) and posterior margin of scutum concave ( Fig. 13a ).

Females: Bee mostly green, posterior margin of scutum concave ( Fig. 13f ) and propodeum moderately strigaterugose dorsally ( Fig. 13f ).

Description. Males: Measurements: UID 0.69–0.87 mm. LID 0.58–0.69 mm. AOD 0.21–0.24 mm. IAD 0.16– 0.19 mm. OAD 0.37–0.45 mm. IOD 0.2–0.25 mm. OOD 0.21–0.27 mm. GW 0.17–0.19 mm. EW 0.25–0.36 mm. ML 0.1–0.17 mm. SL 0.28–0.33 mm. FL 4.13–4.18 mm.

Colouration: Clypeus, supraclypeal area, frons, paraocular area, scutum, scutellum and propodeum dorsally golden green and metallic. Metasoma T1 can be black or nearly so, T2 onwards green, dark along posterior edges.

Sculpturing: Paraocular area colliculate and some messy striae below antennal sockets, longitudinal striae posteriorly and proximally above antennal socket. Frons mostly longitudinal striae, transverse striae under ocelli and striae messy. Supraclypeal area mostly finely colliculate. Clypeus finely colliculate. Vertex punctures fine, close and open. Scutum anteriorly finely colliculate and lineolate; medially and posteriorly finely colliculate. Scutellum punctation close and sparse. Propodeum; dorsally strong striae, weak medial anterior groove or coarsely strigaterugose; laterally fine to moderately colliculate or ventral and anterior striae curve towards each other and can meet; posteriorly finely colliculate, transverse or diagonal striae medially and transverse striae ventrally and proximally with striae almost forming circles with dorsal striae.

Morphology: Scape extends to or below anterior margin of medial ocellus. Interantennal distance greater than diameter of socket. Labrum simple. Clypeus not depressed medially. Area posterior of vertex with strong and close striae. Posterior margin of Scutum shape concave. Gonostylus extends beyond gonocoxite, dorsoapical crest of gonocoxite weak. Gonobase relatively narrow.

Females: Measurements: UID 0.78–0.79 mm. LID 0.79–0.8 mm. AOD 0.26–0.27 mm. IAD 0.12 mm. OAD 0.43–0.44 mm. IOD 0.19–0.22 mm. OOD 0.23 mm. GW 0.25–0.33 mm. EW 0.34–0.43 mm. BL 5.56–5.61 mm. ML 0.11–0.12 mm. SL 0.33–0.39 mm. FL 4.51–4.7 mm.

Colouration: Clypeus anteriorly black; posteriorly golden green and metallic. Whole clypeus partly iridescent. Supraclypeal area golden green and metallic. Frons golden green and metallic. Paraocular area golden green and metallic. Scutum green and yellow. Scutellum yellow, blue and green. Propodeum dorsally golden green and metallic. Metasoma T1 black or nearly so, T2 onwards dark green or green, dark along posterior edges.

Sculpturing: Paraocular area colliculate, fine and dense longitudinal striae posteriorly and proximally above antennal socket with fine striae. Frons mostly fine and dense longitudinal striae. Supraclypeal area mostly finely colliculate. Clypeus finely colliculate. Vertex punctures fine close and open. Scutum anteriorly finely colliculate or lineolate; medially and posteriorly finely colliculate. Scutellum punctation close and open. Propodeum; dorsally strong striae, strong medial anterior groove and moderately strigate-rugose; laterally finely colliculate, some striae anteriorly and dorsally and ventrally; posteriorly finely colliculate and striae originating ventrally and medially almost forms circles with dorsal striae. Pygidial plate with few minute sparse punctures.

Morphology: Scape extends to above vertex. Interantennal distance less than or about equal to diameter of socket. Labrum with 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 concave.

Comments. Although H. concavus has only been sampled up to 810 m asl, it is possible that it extends higher in elevation as we have not sampled the highest elevation on Taveuni.

Distribution. Homalictus concavus has only been sampled from the island of Taveuni ( Fig. 14 ) at elevations between 700 m asl and 810 m asl; Taveuni’s highest elevation is 1,241 m asl.

Etymology. The name concavus is Latin for ‘concave’ and refers to the concave posterior scutal margin in both the males and females of this species.

Figures

FIGURE 1. Propodeum dorsally showing (a) coarsely, (b) moderately and (c) finely strigate-rugose sculpturing. Fovea along anterior inner margin of eye (d) present and (h) absent. Supraclypeal area showing (e) mostly moderately, (f) mostly finely and (g) entirely finely sculpturing.

FIGURE 13. Homalictus concavus 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 14. Collection localities of Homalictus concavus sp. nov. from specimens with identity confirmed by mtDNA COI gene. Sample size is 15.