Patrus phetchabunensis, Suksai & Gustafson & Sites & Sangpradub, 2021

Suksai, Benjamart, Gustafson, Grey T., Sites, Robert W. & Sangpradub, Narumon, 2021, Review of the Patrus landaisi species group from Thailand with description of three new species (Coleoptera, Gyrinidae), Zootaxa 4991 (3), pp. 561-591 : 579-582

Patrus phetchabunensis sp. nov.

( Figs. 2F , 3F , 4F , 10 , 13D , 14B )

Type material. HOLOTYPE: male (card mounted; aedeagus in microvial), “ THAILAND: Phitsanulok / Province Phu Hin / Rhongkla National Park / Huai Khamuen Noi Waterfall : 10.IV.2003 // 16°59’N 101°60’E / 1220 m a.s.l. / coll: CMU team” ( UMC).

PARATYPES (163 exs): THAILAND: Loei Province: Phu Kradueng Natl. Park, Phra Ong Waterfall, Si Than Subdistrict , Phu Kradueng District , 16°52’08.2”N 101°46’31.3”E, 23.V.1996, leg. N. Sangpradub, 1 male ( KKU) ; same locality except for, Tarn Sawan Waterfall, Si Than Subdistrict, Phu Kradueng District , 16°52’55.3”N 101°46’44.6”E, 1173 m a.s.l., 7.III.2011, leg. N. Sangpradub, 1 male ( THNHM) ; same locality except for, Tham Yai Waterfall, Si Than Subdistrict, Phu Kradueng District , 16°52’59.9”N 101°46’46.4”E, 1197 m a.s.l., 21.V.1995, leg. N. Sangpradub, 1 male ( KKU) ; same locality except for, 23.X.1995, leg. N. Sangpradub, 2 females ( KKU, THNHM) , 1 male ( THNHM) . Phitsanulok Province: Phu Hin Rongkla Natl. Park., Huai Khamuen Noi Waterfall , 16°59’N 101°00’E, 1220 m, 17.I.2003, leg. CMU team, 1 female ( UMC) ; same locality except for, 10.II.2003, leg. CMU team, 1 female ( UMC) ; same locality except for, 17.III.2003, leg. CMU team, 1 male, 1 female ( UMC) ; same locality except for, 10.IV.2003, leg. CMU team, 2 males ( UMC) , 7 females ( KKU, THNHM, UMC) ; same locality except for, 5.V.2003, leg. N. Changthong, 5 males, 3 females ( UMC) ; same locality except for, 5.VI.2003, leg. N. Changthong, 1 male ( KKU) ; same locality except for, stream btw Rd 2113, Man Daeng Waterfall , 12.VI.1998, leg. R.W. Sites & K.B. Simpson, L-186, 2 males, 9 females ( UMC) ; same locality except for, 1 male ( THNHM) ; same locality except for, L-187, 8 males ( KKU, THNHM, UMC) , 8 females ( KKU) ; same locality except for, Man Daeng Noi at trail, 16º57’N 101°03’E, 1600 m a.s.l., 10.IV.2003, leg. CMU team, 5 males, 8 females ( UMC, THNHM) ; same locality except for, 5.V.2003, leg. N. Changthong, 5 males, 9 females ( UMC) ; same locality except for, 12.VII.2003, leg. N. Changthong, 1 male, 1 female ( UMC) ; same locality except for, 20.VII.2002, leg. CMU team, 2 females ( UMC) ; same locality except for, Romglao Waterfall , 16°59’N 101°00’E, 1190 m a.s.l., 22.V.2002, leg. CMU team, 1 female ( UMC) ; same locality except for, 17.III.2003, leg. CMU team, 1 female ( UMC) ; same locality except for, 10.IV.2003, leg. CMU team, 2 males ( UMC) , 6 females ( UMC, THNHM) ; same locality except for, 5.VI.2003, leg. N. Changthong, 6 males, 10 females ( UMC) ; Waterwheel Falls , 16°59’N 101°00’E, 1280 m a.s.l., 22.IV.2002, leg. CMU team, 1 female ( UMC) ; same locality except for, 20.VII.2002, leg. CMU team, 2 females ( UMC) ; same locality except for, 10.II.2003, leg. CMU team, 4 males, 5 females ( UMC) ; same locality except for, 5.V.2003, leg. N. Changthong, 8 males, 15 females ( UMC) ; same locality except for, 12.VII.2003, leg. N. Changthong, 4 males, 2 females ( UMC) .

Additional material. THAILAND: Loei Province: Phu Kradueng Natl. Park, stream near Tham Sor Noe Waterfall , 1200–1250 m a.s.l., 28.XII.1999 (16), leg. P. Mazzoldi, 7 exs ( PMI) ; same locality except for, stream betw. Ano Dat Pond and Tham Sor Noe Waterfall , 28.XII.1999 (15), leg. P. Mazzoldi, 112 exs ( PMI) ; same locality except for, 16°52’N 101°49’E, 16–18.V.1999, leg. D. Hauck, 1000 m a.s.l., 4 exs ( PMI) ; same locality except for, Phu Rua Natl. Park , 17°30’N 101°21’E., 1100 m a.s.l., 6, 9.V.1999, leg. D. Hauck, 4 exs ( PMI) ; same locality except for, upstream from Huai Phai Waterfall , 26.XII.1999 (8), 1000 m a.s.l., leg. P. Mazzoldi, 2 exs ( PMI) ; same locality except for, 26.XII.1999 (9), 1200 m a.s.l., leg. P. Mazzoldi, 76 exs ( PMI) . Nan Province: Doi Phu Ka Natl. Park, Ton Tong Waterfall , stream in evergreen forest, 1000–1100 m a.s.l. (28), 3.I.1999, leg. P. Mazzoldi, 6 exs ( PMI) ; same locality except for, road to Ton Tong Waterfall , small stream, 1240 m a.s.l. (27), 3.I.1999, leg. P. Mazzoldi, 6 exs ( PMI) . Phitsanulok Province: Phu Hin Rongkla Natl. Park. , 27.III.1994, leg. W. Shepard // WDS A 1047, 23 exs (19 NHMW; 4 PMI) ; same locality except for, stream near Huai Khamuen Noi Waterfall , 1200 m a.s.l., 25.XII.1999 (6), leg. P. Mazzoldi, 19 exs ( PMI) .

Diagnosis. Body form in lateral view weakly dorsoventrally convex; elytral glabrous region of male ( Figs. 2F , 10A ) cordiform, along suture extending ca. 7/9 length of elytra, laterally expanded in anterior 2/3 to considerably wider than pronotal glabrous region, posterior 1/3 strongly acuminate with weakly rounded margins; female elytral glabrous region similar to male ( Figs. 3F , 10E ), except with weaker apical acumination; elytral apex of both sexes similar, obliquely truncate without apicolateral sinuation, epipleural angle distinct, weakly rounded; male protibia ( Fig. 4F ) cleaver shaped, constricted in basal 2/5, protibial apex truncate with prominent distolateral angle; male protarsus ( Fig. 4F ) ca. 1/2 length of protibia, protarsomeres width gradually decreasing apically; mesoventrite without medial pit; aedeagus ( Fig. 10B ) with median lobe evenly tapered, apex constricted in lateral view ( Fig. 10C ); female reproductive tract ( Fig. 10G ) without additional sclerite between gonocoxae ( Fig. 10F ), fertilization duct as in Fig. 10H .

Description. Habitus. Size. Male: TL = 10.0–12.0 mm, TW = 6.0–7.0 mm; female: TL = 9.5–11.0 mm, TW = 5.0– 6.5 mm.

Body form elongate oval, evenly attenuated anteriorly and posteriorly, maximum width just posterior of humeral angle; in lateral view dorsoventrally weakly convex, maximum convexity posterior to scutellar region, evenly depressed anteriorly and posteriorly.

Coloration ( Figs. 2F , 3F ). Dorsally head, pronotum, and elytra margined with golden pubescence; glabrous regions of head pronotum and elytra black with reticulation creating brassy sheen. Pronotal and elytral lateral margins dark. Venter dark, reddish-brown to black. Middle and hind legs from trochanter to tarsus and ultimate abdominal ventrite lighter in color, red to orangish-red.

Head. Head capsule broad, convex. Labrum short, ca. 3.5× wider than long; setose medially with setae situated in large deep punctures; apex broadly rounded. Clypeus narrow, ca. 1/2 width of labrum; strongly reticulate and densely punctured, reticulation hatched in appearance with numerous short, well-impressed transverse lines. Frons similarly with strong hatched reticulation and dense punctation; pseudofrontal ridge present; furrow beneath pseudofrontal ridge without setae. Vertex also with strongly impressed hatch reticulation and dense punctation between dorsal eyes, reticulation becoming effaced in narrow band on occipital region. Dorsal eye delimited by strong orbital furrow; distance between dorsal eyes ca. 2.5× diameter of an eye; interorbital area strongly setose.

Thorax. Pronotum ( Figs. 2F , 10A ) with narrow lateral margins; pronotal transverse impressed line absent; lateral pubescence anteriorly extending onto pronotal disc as far as middle of dorsal eye; pronotal glabrous region densely and uniformly punctate with small weakly impressed punctures, strongly reticulate with uniform well-impressed hatched reticulation similar to frons and vertex. Scutellar shield visible. Protrochanter with setose line along ventral (anterior) face. Profemur with setigerous punctures along anterior margin of ventral face, posterior margin of ventral face with row of setae along basal 2/3 ending with patch of longer denser setae. Protibia ( Fig. 4F ) cleaver shaped in males, constricted in basal 2/5 creating weakly sinuate ventral (inner) margin; distal apex truncate, distolateral angle prominent. Male protarsus ( Fig. 4F ) ca. 1/2 length of protibia, protarsomeres with distolateral angle round, not overlapping following tarsomere, lateral margins weakly rounded, fifth tarsomere 1.5× length of fourth, with lateral margins weakly rounded. Elytra ( Figs. 2F , 10A ) with narrow lateral margins gradually widened apically; glabrous region cordiform, along suture extending ca. 7/9 length of elytra, laterally expanded in anterior 2/3 to just wider than pronotal glabrous region, posterior 1/3 weakly attenuated with weakly rounded margins; reticulation and punctation similar to pronotal glabrous region; elytral apex obliquely truncate, without apicolateral sinuation, epipleural angle distinct, weakly rounded, sutural angle straight forming near 90° angle. Mesoventrite without medial pit.

Sexual dimorphism. Female smaller in size, less laterally expanded near elytral mid-length resulting in narrow maximum width. Glabrous cordiform region of elytra less acuminate posteriorly ( Figs. 3F , 10E ) due to weaker convexity of lateral pubescence of elytra in apical 1/3. Forelegs smaller, female protibia narrower with less pronounced constriction in basal 2/5 and weaker sinuation of the ventral margin.

Male genitalia. Aedeagus ( Fig. 10B ) with median lobe ca. 4/5 length of parameres, evenly tapered, apex in lateral view noticeably constricted ( Fig. 10C ), operculum as in Fig. 10D ; parameres narrowly rounded apically ( Fig. 10B ).

Female genitalia. Reproductive tract with large sac-like spermatheca ( Fig. 10G ); fertilization duct sclerotized, highly convoluted ( Fig. 10H ); small sclerite present posterior to oviduct; additional round sclerite between gonocoxae absent; gonocoxae narrow, apically broadly rounded, laterally with nearly straight margins ( Fig. 10F ).

Variation. There is considerable variation in size among the specimens examined. There is also noticeable variation in maximum width particularly in males, with larger males being wider than other males with smaller body lengths.

Differential diagnosis. Patrus phetchabunensis sp. nov. is most similar to P. salvazai . Males of these two species share a cleaver-shaped protibia which differentiates them from the other P. landaisi species group members in Thailand. Patrus phetchabuensis sp. nov. can be distinguished from P. salvazai by having the protibial constriction limited to the basal 2/5 ( Fig. 4F ), whereas in P. salvazai ( Fig. 4G ) the constriction extends to half the protibial length. The shape of the cordiform glabrous region in males of P. phetchabunensis sp. nov. is relatively wider anteriorly near the humeral region ( Figs. 2F , 10A ) than that of P. salvazai ( Figs. 2G , 11A ). The aedeagus of P. phetchabuensis sp. nov. differs considerably from that of P. salvazai in having an evenly tapered median lobe ( Fig. 10B–C ), compared to that of P. salvaza i which is constricted close to mid-length, with the apex arcuate in lateral view ( Fig. 11B–C ). Females of P. phetchabunensis sp. nov. can be distinguished from those of P. salvazai in having the elytral apex obliquely truncated ( Fig. 10E ) rather than rounded ( Fig. 11E ).

Etymology. The name of the species, phetchabunensis , is an adjective in reference to the Phetchabun mountain range where the type material for this new species was collected.

Distribution. This species is currently known from Phu Hin Rongkla National Park and Phu Kradueng National Park ( Fig. 13D ) and Phu Rua National Park, which are all within the Phetchabun mountain range ( Fig. 14B ); this is an area exhibiting high levels of endemism among aquatic insects ( Sites & Polhemus 2001; Vitheepradit & Sites 2007), including whirligig beetles ( Gustafson et al. 2016). Additonally, this species has been collected from Doi Phu Ka National Park which is located within the Luang Prabang mountain range ( Fig 14B ).

Figures

FIGURE 2. Dorsal habitus of males of P. landaisi species group: (A) P. apicalis; (B) P. corpulentus; (C) P. garuda sp. nov.; (D) P. landaisi; (E) P. nanensis sp. nov.; (F) P. phetchabunensis sp. nov.; (G) P. salvazai; (H) P. subapicalis. Scale bars = 4 mm.

FIGURE 3. Dorsal habitus of females of P. landaisi species group: (A) P. apicalis; (B) P. corpulentus; (C) P. garuda sp. nov.; (D) P. landaisi; (E) P. nanensis sp. nov.; (F) P. phetchabunensis sp. nov.; (G) P. salvazai; (H) P. subapicalis. Scale bars = 4 mm.

FIGURE 4. Left protibia and protarsus of males of P. landaisi species group: (A) P. apicalis; (B) P. corpulentus; (C) P. garuda sp. nov.; (D) P. landaisi; (E) P. nanensis sp. nov.; (F) P. phetchabunensis sp. nov.; (G) P. salvazai; (H) P. subapicalis. Scale bars = 2 mm.

FIGURE 10. Patrus phetchabunensis sp. nov.: (A) male pronotum and elytra, dorsal view, scale bar = 4 mm; (B) aedeagus, dorsal view, scale bar = 1 mm; (C) apex of median lobe, lateral view, scale bar = 1 mm; (D) apex of median lobe, ventral view showing operculum, scale bar = 1 mm; (E) female pronotum and elytra, dorsal view, scale bar = 4 mm; (F) gonocoxae, ventral view; (G) female reproductive tract, ventral view, scale bar = 1 mm; (H) fertilization duct, ventral view.

FIGURE 11. Patrus salvazai: (A) male pronotum and elytra, dorsal view, scale bar = 4 mm; (B) aedeagus, dorsal view, scale bar = 1 mm; (C) apex of median lobe, lateral view, scale bar = 1 mm; (D) apex of median lobe, ventral view showing operculum, scale bar = 1 mm; (E) female pronotum and elytra, dorsal view, scale bar = 4 mm; (F) gonocoxae, ventral view; (G) female reproductive tract, ventral view, bursal gland not shown, scale bar = 1 mm; (H) fertilization duct, ventral view.

FIGURE 13. Habitats of P. landaisi species group: (A) stream at Siriphum Waterfall, Doi Inthanon National Park, Chiang Mai Province, habitat of P. garuda sp. nov. and P. subapicalis; (B) Benjamart Suksai in habitat of P. apicalis and P. salvazai at Nam Kuen stream, Chiang Rai Province; (C) shallow stream close to Ban Thai Samakkhi, Chiang Rai Province, habitat of P. landaisi and P. salvazai; (D) Tham Yai Waterfall Phu Kradueng National Park, Loei Province, habitat of P. phetchabunensis sp. nov.; (E) puddle in dry stream bed close to Ban Phithak Thai, Chiang Rai Province, habitat of P. landaisi and P. salvazai; (F) P. landaisi and P. salvazai from puddle in dry stream habitat close to Ban Thai Samakkhi, Chiang Rai Province.

FIGURE 14. (A–B) Distribution records of the P. landaisi species group in Thailand.