Nososticta stueberi, Theischinger & Mitchell & Richards & Polhemus, 2023

Theischinger, Günther, Mitchell, Andrew, Richards, Stephen J. & Polhemus, Dan A., 2023, Systematics of the Nososticta salomonis complex (Odonata: Zygoptera: Platycnemididae), Zootaxa 5296 (2), pp. 101-146 : 125-127

Nososticta stueberi sp. nov.

( Figs 42–49 , 61, 62 , Map 4 , Pl. 5)

Holotype. ♁, SAMA 07-001596 , Papua New Guinea, East Sepik Province, Iniok (4°17.296’S, 142°01.236’E; 45 m a.s.l.), 15-vi-2010, S. Richards; deposited in the South Australian Museum, Adelaide, Australia.

Paratypes. Papua New Guinea: 1 ♁, 2 ♀♀, SAMA 07-001594 , 07-001595 , 07-001689 , same details as holotype, 14–17-vi-2010, S. Richards; deposited in the South Australian Museum, Adelaide, Australia. 3 ♁♁, 1 ♀, BPBMENT 0000081215–81218 , Milne Bay Prov., Bwaona River , E of Mila, upper Sagarai River basin, 90 m a.s.l., 10°30’14”S, 150°18’50”E, water temp. 28° C, 07-iv-2002, CL, 7165 , D.A. & J.T. Polhemus; 3♁♁, BPBMENT 0000081223–81225 , Milne Bay Prov., Sideia Island, Kwabunamoa River headwaters in south-central interior , 35– 40 m a.s.l., 10°35’59”S, 150°50’54”E, water temp. 26.5° C, 15-i-2004, CL 7288 , D.A. & J.T. Polhemus ; 2♀♀, BPBMENT 0000081221–81222 , Milne Bay Prov., D’Entrecasteaux Is., Fergusson Is., Mebulibuli Creek trib., S. of Basima , 15–75 m a.s.l., 9°30’42”S, 150°52’06”E, water temp. 24° C, 24-viii-2002, CL 7181 , D.A. Polhemus; 1 ♁, 1 ♀. BPBMENT 0000081219–81220 , Milne Bay Prov., Muguwe Creek, nr Naura , 26 km W of Alotau, 70 m a.s.l., 10°17’20”S, 150°12’10”E, water temp. 25.5° C, 09-iv-2002, CL 7169 , D.A. & J.T. Polhemus; all deposited in the Bishop Museum, Honolulu, Hawaii. 2 ♁♁, 3 ♀♀, RMNH. INS. 1153705–1153709 , NE New Guinea, Morobe Dist. , 6 mi. W of Lae, 17–26-x-1972 ex coll. Donnelly; 1 m, RMNH. INS. 1153639 , NE New Guinea, Morobe Dist., creek nr. Gabensis, Wau Rd , 17–26-x-1972 ex coll. Donnelly; all deposited in Naturalis Biodiversity Center, Leiden, Netherlands . 1 ♀, RMNH. INS. 1153640 , Camp 1 [Menapi, Cape Vogel Peninsula, 6.5 km. E. of Baniara , 0-20 m, 9°45’37”S, 149°56’00”E, Fourth Archbold Expedition; see Brass (1956)], 24.III.1953 ; 2 ♀♀, RMNH. INS. 1153641 , 1153642 , Camp 1 [Menapi, Cape Vogel Peninsula, 6.5 E. of Baniara , 0-20 m, 9°45’37”S, 149°56’00”E, Fourth Archbold Expedition; see Brass (1956)], 2.iv.1953 ; 2 ♁♁, 3 ♀♀, RMNH. INS. 1153716 , 1153643–1153646 , Camp 1 , 10.iv.1953 ; 1 ♁, RMNH. INS .1153647 , Camp 2 , 10.v.1953 ; 1 ♁, RMNH. INS.1153648 , Camp 7 [Peria Creek, off Kwagira River, 50 m., nr. Awani village , vic. 9°39’06”S, 149°23’47”E, Fourth Archbold Expedition; see Brass (1956)], 23.VIII.1953; all deposited in Naturalis Biodiversity Center, Leiden, Netherlands . Indonesia: 1 ♁, 1♀, RMNH. INS .1153649 , 1153650 , N New Guinea, iii-1931, W. Stüber; 3 ♁♁, RMNH. INS. 1153651–1153653 , N. N. Guinea, 11–xii-1930, W. Stüber; 24 ♁♁, RMNH. INS. RMNH. INS. 1153717 , 1153718 , 1153654–1153675 , N. New Guinea, 27.viii–4.ix.1930, W. Stüber; 1 ♁, 1 ♀, RMNH. INS. 1153676 , 1153677 , cop., N. N. Guinea, 27.viii– 4.ix.1930, W. Stüber ; 9 ♀♀, RMNH. INS. 1153678–1153686 , N. New Guinea, Humboldt Baai , iii-1931 , W. Stüber; 1 ♁, RMNH. INS. 1153687 , N. N. Guinea, Humboldt Baai, 19, W. Stüber; or ii-1953, Tamivlabta ; 8 ♀♀, RMNH. INS. 1153688–1153695 , N. New Guinea, Humboldt Baai , i-1932 , W. Stüber; or Kressi , 300 m, 120 km; 1 ♁, 1 ♀, RMNH. INS. 1153696 , 1153697cop ., N. New Guinea, Humboldt Baai , xii-1932, W. Stüber; or Agaffo Sago; 3 ♁♁, 4 ♀♀, RMNH. INS. 1153698–1153704 , N. N. Guinea, Humboldt Baai , 9.iii–11.iv.1936, W. Stüber; or Berap Lakes; 1 ♁, RMNH. INS .1153710 , Hollandia, 23-vi-1938, Toxopeus; 5 ♁♁, RMNH. INS. 1153711–1153715 , Hollandia, vii-1938, L.J. Toxopeus; all deposited in Naturalis Biodiversity Center, Leiden, Netherlands .

Etymology. The species is dedicated to its probable discoverer, Wilhelm Stüber (1877–1942), collector extraordinaire of New Guinean dragonflies, including numerous individuals of this species. The name is a noun in the genitive case.

Description of holotype

Head. Largely black; only base of labium pale grey and transverse frontal bar from eye to eye blue; a faint ill-defined pale brown mark only barely detectable between antennal base and lateral ocellus.

Thorax. Pronotum black with tiny inner spot and small blue mark distally on anterior lobe, very close to large blue lateral patch on median lobe, pleura largely bright blue, black along sutures and at rear of epimeron. Synthorax with pleura largely black except following areas of blue: ante-humeral patch, markedly shorter than 1/2 length of mesanepisternum, basally not more than 1 and 1/2 times as wide as at truncate dorsal end; patch covering at least dorsal 3/4 the length and approximately posterior 1/2/ to 3/4 width of mesepimeron, partly connected with stripe across whole length and anterior 3/4 of metepisternum; patch across posterior half of metepimeron, dorsal half of its anterior margin convex; posterolateral tip of meso- and metakatepisternum. Postcoxae largely blue and black; poststernum pale blue with small and narrow patches of blackish brown to black. Legs: Coxae and trochanters blue and black, legs otherwise black, with only base of pro- and mesofemur and basal inner 1/3 of metafemur partially pale blue. Wings: membrane with very faint greenish brown tinge, venation black; pterostigma black, about twice as long as wide; postnodals 14/12–13.

Abdomen. S1 dorsally black, laterally largely pale blue; S2 largely black, pale blue adjacent to genitalia but dorsal blue mark absent; S3–7 dorsally black, ventrally margined bluish white, S3–6 with blue mid-dorsal mark very close to base; S8 largely blue, narrowly lined with black basally, more widely and irregularly lined with black apically, sometimes divided by very fine black mid-line; S9 and S10 black. Superior anal appendages largely blue, inferiors brownish black.

Dimensions. Hind wing 19.0 mm; abdomen (including anal appendages) 31.5 mm.

Description of female

Head. Much as in male, but transverse frontal bar from eye to eye whitish yellow.

Thorax. Pronotum much as in male, but anterior lobe with larger outer mark only, bluish white and narrowly separated from large patch of same colour on median lobe, posterior lobe with vertical dorsal and horizontal ventral lobe; propleura much as in male but pale areas largely bluish white instead of blue. Synthorax with pleura largely black. Ante-humeral patch pale yellow to brownish, less than 40% length of mesanepisternum, about 1/4 to 1/3 as wide as long, narrowly oval to almost parallel sided. Bluish white areas include: a remnant mesepimeral patch, variable in length and somewhat in width, completely fused with metepisternal stripe; metepimeral stripe; more extensive posterolateral tip of meso- and metakatepisternum. Postcoxae bluish white and black; poststernum bluish white with largely narrow elongate patches of brown to black. Legs: Coxae largely pale to bluish white, meso-and metacoxa black anterobasally, trochanters black and pale yellow; legs otherwise dark, with base of femora pale to dull yellow. Wings: membrane almost clear, venation black; pterostigma much as in male, greyish brown; postnodals 14–17/12–14.

Abdomen. S1 and S2 dorsally largely black, laterally largely bluish white; S3–7 dorsally black, ventrally narrowly margined whitish blue to pale yellow, S3–6, with very short bluish white dorsal mark very close to base, often divided by dark midline; S8 black with ventral edge pale yellow; S9 and S10 black. Anal appendages pale yellow, inferior anal lamina brown and yellow; ovipositor brownish to dull yellow, valves and supra-anal plate black.

Dimensions. Hind wing 18.3–20.0 mm; abdomen 28.0– 31.3 mm.

Variation in the male paratypes. Postnodals 13–15/12–13; pterostigma ranging in colour from yellowish grey and yellowish brown (due to immaturity and method of preservation) to black and in proportion from slightly less to slightly more than twice as long as wide; hind wing 16.6–19.1 mm; abdomen (including anal appendages) 27.6–32.0 mm.

Affinities. Based on the present study ( Fig. 6 ), N. stueberi sp. nov. is closest to N. tagula sp. nov. and N. boonei sp. nov.

Differential diagnosis. Nososticta stueberi sp. nov. is the only species of the N. salomonis complex with the blue/pale ante-humeral patch in both sexes markedly shorter than 1/2 the length of the mesanepisternum and close to parallel sided in the female. There appears to be limited morphological variation across this species’ extensive known distribution.

Distribution and habitats. Nososticta stueberi has a broad distribution across northern and eastern New Guinea extending from at least the Jayapura region in Papua Province, Indonesia in the west to Alotau in Milne Bay Province, Papua New Guinea, in the east ( Map 4 , Pl. 5). It occurs in both primary and degraded forest habitats where adults perch on twigs or low foliage along small, shallow streams. It also occurs in forest clearings some distance from water. One of us (DP) has collected this species at multiple sites across the New Guinea region, all of which were creeks or small rivers with cobble and gravel substrates (for examples, see Plate 5 , Bwaona River and Muguwe Creek). Similarly, the Peria Creek habitat at Camp 7 of the 4 th Archbold Expedition where this species was taken is described by Brass (1956) as having “...a gravelly bed about 50 meters wide. In May it flowed about knee deep, but in August and early September there remained only deep pools of clear water.” It therefore seems that this species may tend to favour such habitats.

Figures

MAP 4.—Distribution of species of the Nososticta salomonis complex on mainland New Guinea.

PLATE 5.—Nososticta stueberi sp. nov. habitats. Top = Lowland swamp forest, Papua New Guinea, East Sepik Province, Iniok. S.J. Richards photo, 2010. Bottom: Papua New Guinea, Milne Bay Prov., New Guinea. Left = Bwaona River, E. of Mila village, CL 7165. Right = Muguwe Creek, W. of Naura village, CL 7169. D. A. Polhemus photos, 2002. For detailed data on individual localities see text.

FIGURE 6. Bayesian tree from concatenated (all genes) data set. Numbers above branches are BI posterior probabilities and ML bootstrap values shown only if ≥ 0.9 and 70%, respectively.

FIGURES 42–49. Nososticta stueberi sp. nov. (42–45) male: (42) in life; (43, 44) synthorax: (43) lateral; (44) schematically; (45) superior anal appendage; (46–49) female: (46) in life; (47, 48) synthorax: (47) lateral; (48) schematically; (49) antehumeral patch, frontal, 2 additional specimens.

FIGURES 55–65. Nososticta species. (55, 56) male abdominal segment 2, dorsal: (55) N. africana (Schmidt); (56) N. tagula sp. nov.; (57–65) synthorax, schematically: (57) N. africana (Schmidt), female; (58) N. tagula sp. nov., female; (59, 60) N. hedigeri sp. nov.: (59) male; (60) female; (61, 62) N. stueberi sp. nov.: (61) male; (62) female; (63) N. chrismulleri Theischinger & Richards, male; (64, 65) N. boonei sp. nov.: (64) female; (65) male.