Psenulus maculatus maculatus van Lith, 1962

Figs 4E-4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17E, 18I, J, 19I, J, 20E, 21E

Psenulus maculatus maculatus van Lith 1962: 61-62, figs 69-72. Holotype: ♀; Malaysia, Penang, 25 mi Sungai Penang Hills; type repository unknown, formerly H.T. Pagden coll.

Material examined.

China, Hong Kong • 1♂; Tung Chung; 22°16'55"N, 113°55'43"E; 29 May-12 Jun. 2018; C. Taylor and Cheung Shun Chi leg.; Malaise trap; HKU • 1♂; Pak Sha O; 22°26'59"N, 114°19'04"E; 70 m a.s.l.; 14 May-05 Jun. 2011; C. Barthélémy; Malaise trap, ref.: M092CHy19; CBC • 1♀; ibid.; 23 May 2020- 06 Jun. 2020; ibid.; ref.: M492. C.Hy. 1; CBC • 1♂; Mang Kung Wo; 22°22'06"N, 114°15'12"E; 60 m a.s.l.; 18 Aug.-01 Sep. 2018; ibid.; ref.: M362CHy8; CBC • 1♂; ibid.; 04-18 May 2019; ibid.; ref.: M413CHy5; CBC • 2♀; ibid.; 17-31 Mar. 2018; ibid.; ref.: M336CHy7A and B; CBC • 1♀; ibid.; 28 Apr.-12 May 2018; ibid.; ref.: M345CHy2; CBC • 1♀; ibid.; 4-18 Aug. 2019; ibid.; ref.: M359CHy7; CBC • 1♀; ibid.; 01-15 Sep. 2019; ibid.; ref.: M365CHy7; CBC • 1♀; ibid.; 9-23 May. 2020; ibid.; ref.: M489CHy2; CBC • 1♂; ibid.; 17 Aug. 2020 - 01 Sep. 2020; ibid.; ref.: M509CHy2; CBC .

Standard ratios.

Males (n = 5): L = 5.-6.6 mm (mean = 5.9 mm); CR = 1.21-1.33 (mean = 1.28); OOR = 0.76-0.89 (mean = 0.84); FLR = 1.00-1.23 (mean = 1.09); FRR = 0.66-0.70 (mean = 0.69); MR = 1.35-1.61 (mean = 1.54); OMR = 0.94-1.01 (mean = 0.97); PR = 0.7-2.53 (mean = 1.21); PFR = 0.88-1.05 (mean = 0.94). Females (n = 7): L = 6.4-7.1 mm (mean = 6.53 mm); CR = 1.22-1.35 (mean = 1. 28); OOR = 0.71-0.86 (mean = 0.77); FLR = 1.25-1.5 (mean = 1.38); FRR = 0.60-0.67 (mean = 0.64); MR = 1.36-1.64 (mean = 1.47); OMR = 0.89-0.99 (mean = 0.92); PR = 1.05-1.83 (mean = 1.32); PFR = 0.82-0.94 (mean = 0.87).

Description.

Male: Antenna with small tyloids present on F7 to F11. Clypeus (Fig. 21E) with two acute ventral teeth separated by rounded emargination, remainder of clypeal margin evenly rounded. Subantennal carina well developed (Fig. 7E); interantennal carina narrow, not broadened dorsally, Mesosoma mostly polished, mesoscutum moderately punctate with punctures separated by about their own diameter (Fig. 11E), remainder of mesosoma more sparsely punctate; prescutal sutures short, ending about anterior level of tegula; episternal sulcus broadly foveolate (Fig. 13E); propodeal enclosure with few pairs of longitudinal carinae; remainder of propodeum coarsely reticulate (Fig. 15E) except narrowly smooth anterolaterally. Petiole subcylindrical, T1 distinctly swollen (Fig. 5E). Fore wing (Fig. 19J) with first recurrent vein joining first submarginal cell near apex; second recurrent vein joining third submarginal cell near base.

Head black with appressed silvery pubescence (Figs 7E, 9E); antenna with most of scape, venter of pedicel and venter of flagellum basally yellow, dorsoapical spot on scape, dorsum of pedicel and remainder of flagellum blackish; mandible yellow with black tip. Mesosoma mostly black, the following yellow (Figs 5E, 11E, 13E): pronotal collar, pronotal lobe; mesoscutum with two longitudinal submedian stripes inside prescutal sutures, broadening posteriorly, ending prior to posterior margin of mesoscutum, often narrowed or absent in anterior half of mesoscutum, long posterolateral spot also present on mesoscutum; tegula; large spot on axilla; broad anteromedian spot on scutellum, as well as narrow stripe along posterior margin laterally behind wing insertion; metanotum; mesopleuron with two spots dorsally anterior and posterior to oblique mesopleural suture; propodeum with paired spots posteriodorsally and laterally. Legs mostly yellow, coxae black basally; fore and mid femora posteriorly brown; hind trochanter and dorsum of hind femur brown; hind tibia and tarsus reddish. S1 yellow at very base of petiole, otherwise blackish; T1 dark brown mediobasally; remainder of metasoma mostly reddish except apex of metasoma dark brown.

Female: Clypeus with marginal teeth larger than in male (Fig. 20E). Subantennal carina well developed (Fig. 7E); interantennal carina narrow, not broadened dorsally, Mesosoma mostly polished, mesoscutum moderately punctate with punctures separated by about their own diameter (Fig. 11E), remainder of mesosoma more sparsely punctate; prescutal sutures short, ending about anterior level of tegula; episternal sulcus broadly foveolate (Fig. 13E), propodeal enclosure with few pairs of longitudinal carinae. Propodeum mostly smooth (Fig. 14E), coarse reticulations restricted to marginal ridge along transition between posterior and lateral surfaces. Hind tibia with dorsobasal array of short denticles associated with elongate red spines basad to distinct dorsal groove (Fig. 18I), and transverse row of short red spines antero-apically. Petiole subcylindrical, T1 distinctly swollen (Fig. 5E). Pygidial plate narrow, delineated by distinct carinae that diverge anteriorly (Fig. 16E). Fore wing (Fig. 19J) with first recurrent vein joining first submarginal cell near apex; second recurrent vein joining third submarginal cell near base.

Head black with appressed silvery pubescence (Figs 7E, 9E); antenna with most of scape, venter of pedicel and venter of flagellum basally yellow, dorsoapical spot on scape, dorsum of pedicel and remainder of flagellum blackish; mandible yellow with black tip. Mesosoma mostly black, the following yellow (Figs 5E, 11E, 13E): pronotal collar, pronotal lobe; mesoscutum with two longitudinal submedian stripes inside prescutal sutures, broadening posteriorly, ending prior to posterior margin of mesoscutum, often narrowed or absent in anterior half of mesoscutum, long posterolateral spot also present on mesoscutum; tegula; large spot on axilla; broad anteromedian spot on scutellum, as well as narrow stripe along posterior margin laterally behind wing insertion; metanotum; mesopleuron with two spots dorsally anterior and posterior to oblique mesopleural suture; propodeum with paired spots posteriodorsally and laterally, larger than in male, may be merged into single posterior patch. Legs mostly yellow, coxae black basally; fore and mid femora posteriorly brown; hind trochanter and dorsum of hind femur brown; hind tibia and tarsus reddish. S1 yellow at very base of petiole, otherwise blackish; T1 dark brown mediobasally; remainder of metasoma mostly reddish except apex of metasoma dark brown.

Distribution.

*China (Hong Kong); Malaysia (Penang), Singapore. (van Lith 1962, 1976).

Notes.

The coloration of the mesoscutum has previously been described as having two submedian triangular marks in the posterior half but specimens from Hong Kong vary from as described to having longitudinal yellow stripes extending most of the length of the mesoscutum. Males of this species can readily be distinguished from other Psenulus in the Hong Kong SAR by the presence of tyloids on the underside of the distal antennal segments; females can be distinguished by their prominent subantennal carina and an array of long red spines dorsobasally on the hind femur. Psenulus maculatus also differs from other Hong Kong Psenulus in having the fore and mid femora partially brown instead of entirely yellow.

Psenulus maculatus maculatus was previously known from the Malaysian Peninsula with other subspecies known from Java and Sri Lanka (van Lith 1962, 1978). The discovery of this species in Hong Kong is a new record for China and also extends notably the known distribution of the taxon.

It is the least common of all species and its occurrence confirmed at only three of the 20 sites sampled and never very abundant at any of these sites. Its activity period is the second shortest (after P. ephippius) and spans from March (W11) to September (W38).