Thescelosynchroa, Hsiao & Ondřej Konvička & Chiun-Cheng Ko, 2018

Hsiao, Yun, Ondřej Konvička & Chiun-Cheng Ko, 2018, The world fauna of Synchroidae Lacordaire, 1859 (Coleoptera, Tenebrionoidea, Synchroidae), European Journal of Taxonomy 407, pp. 1-33 : 10-13

Synchroa punctata Newman, 1838

Figs 3A–B , 4A, G , 5A–B, M , 6A–E

Synchroa punctata Newman, 1838: 378 .

Diagnosis

This species can be easily distinguished from other species of Synchroa by the following combination of characters: body densely covered by pale simple setae; pronotum smooth and impunctate in medio-longitudinal part of posterior half, lateral sides almost entirely margined; prosternal process with long oval apex; aedeagus: parameres moderately narrowed apically, abruptly strongly narrowed at apex.

Material examined

UNITED STATES OF AMERICA: 3 larvae, Hemlock Draw , Sauk Co., Wisconsin, 43°21′50″ N, 89°56′49″ W, 30 Mar. 2001, D.S. Biggs leg. (YHC) ; 1 ♀, Hemlock Draw , Sauk Co., Wisconsin, 43°21′46″ N, 89°56′34″ W, 11–20 Jun. 2001, Lindgren Funnel Trap, D. Young leg. (YHC) ; 1 ♂, 1 ♀, same locality data as previous, 6–11 Jul. 2001, Lindgren Funnel Trap, D. Young leg. ( YHC) ; 1 ♂, 2 ♀♀, same locality data as previous, 19–25 Jul. 2001, Lindgren Funnel Trap, D. Young leg. ( YHC); 1 larva, Merrill , Marathon Co., Wisconsin, 22 Feb. 2003, E. Nowak leg. ( YHC); 1 larva, Hemlock Draw, Sauk Co., Wisconsin, 43°21′46″ N, 89°56′57″ W, 21 Apr. 2003, A. Bendlin leg. ( YHC); 5 larvae, Otter Creek, Rock Co., Wisconsin, 27 Apr. 2003, A. Bendlin leg. ( YHC); 1 ex., West Jefferson , 20 km W of Columbus, Ohio, 6 Jun. 2008, Košťál leg. ( OKCZ).

CANADA: 1 ex., Warwick Conservation Area , Ontario, 42.995 N, 81.948 W, Jul. 2014, collector unknown ( OKCZ) ; 1 ex., Ottawa, Stittsville , Ontario, 45.275 N, 75.972 W, 3 Jul. 2014, collector unknown ( OKCZ) ; 1 ex., Cornwall , Ontario, 45.04384 N, 74.71467 W, 14 Jul. 2014, collector unknown ( OKCZ) ; 2 ex., Cornwall , Ontario, 45.04384 N, 74.71467 W, 14 Jul. 2014, collector unknown ( OKCZ) ; 2 ex., Merritt island , Ontario, 43.00255 N, 79.241 W, 16 Jul. 2014, collector unknown ( OKZC) ; 1 ♂, Boucherville , Québec, 45.55 N, 73.42 W, 21 Aug. 2014, collector unknown (YHC) ; 1 ♂, Québec, 46.79416 N, 71.32895 W, 14 Jul. 2015, collector unknown (YHC); 2 ex., Brantford, Ontario , 43.15806 N, 80.35835 W, 27 Jul. 2015, collector unknown ( OKCZ) .

Redescription

COLOUR. Body and legs completely blackish-brown. Antennae brown in some specimens.

Male ( Fig. 3A )

MEASUREMENTS. Length: 9.50–11.50 mm; width: 2.25–2.75 mm.

BODY. Elongate, slightly flattened, elytra rather strongly narrowed posteriorly, covered with pale, elongate and decumbent setae.

HEAD. Eyes lateral, large, emarginate in front of antennal insertions, ratio of eye diameter to interocular space 1.0: 1.5–1.7. Antennae filiform, when directed backwards exceeding the humeri of elytra. Scape cylindrical, wider than other antennomeres, pedicel short, antennomere III–XI somewhat clavate, XI longest, length ca 4.5–4.6 times maximum width. Length ratio of antennomeres as follows: 1.90:1.00: 2.60:2.45: 2.30: 1.95: 1.85: 2.10:2.10: 1.90: 3.20. Apical maxillary palpomere securiform, apical margin moderately rounded, terminal angle somewhat obtuse. Surface lustrous, densely and coarsely punctate; interspaces slightly narrower than puncture diameter.

PRONOTUM. Truncate anteriorly, anterior edge slightly concave, bisinuate posteriorly, with obtuse median lobe, width ca 1.4–1.5 times as long as length, ca 1.6–1.7 times as wide as head. Lateral sides rounded and strongly narrowed in anterior two-thirds toward head, subparallel in posterior one-third, completely or almost completely margined. Anterior angle rounded; posterior angle rectangular and obtuse. Disc slightly flattened medially, surface lustrous, densely and coarsely punctate; spaces between punctures smaller than puncture diameter. Scutellum width ca 1.50–1.70 times length.

ELYTRA. Elongate, narrowed posteriorly, apex rounded, as wide as pronotal width at humeri, length ca 2.6–2.7 times width, surface lustrous. Disc covered with oval punctures, denser in lateral and basal part; interspaces wider than puncture diameter. Nine faint traces of striae in each elytron in dorsal view, stria I fused with II (numbered from suture to lateral side) ( Fig. 4A ), gradually shortened outwards; elytral striae indistinct in some specimens. Prosternum before procoxae about as long as shortest diameter of procoxae. Prosternal process long, margined laterally, long oval, extending well beyond procoxae; length behind procoxae longer than width between procoxae. Width between procoxae ca 0.2 times transverse coxa diameter. Mesoventrite with shallow, oval mesoventral cavity, moderately punctate. Abdominal ventrite V truncate, with lateral sides nearly straight ( Fig. 4G ); sternite VIII concave in middle of apical edge, forming two rounded lobes on both sides, moderately pubescent apically ( Fig. 5B ); sternite IX without spiculum gastrale on apical edge ( Fig. 5M ); tergite VIII without median strut on apical edge, rounded apically, moderately pubescent apically ( Fig. 5A ); tergite IX and X completely fused, rounded apically, densely pubescent on apical edge ( Fig. 5M ).

LEGS. Slender. Tarsomeres simple, tarsal formula 5-5-4. The longest spur of hind tibiae ca 0.3 times as long as first tarsal segment; length ratio of tarsomeres as follows: 2.30: 1.00: 0.55: 0.85 (measured without claws). Claws simple.

AEDEAGUS ( Fig. 6A–E ). Lanceloate, basal piece curved dorsally, lateral sides roundly arcuate, narrowed basically. Parameres narrowly separated apically with a groove in dorsal median part; lateral sides of the aedeagus almost straight, slightly constricted medially ( Fig. 6A–B ) or distinctly widened in middle ( Fig. 6C ), moderately narrowed apically, abruptly strongly narrowed at apex, length ca 3.3–3.5 times maximum width. Median lobe elongate, tapered, strongly narrowed in the apical half.

Female ( Fig. 3B )

MEASUREMENTS. Length: 10.00– 13.50 mm; width: 2.50–3.00 mm.

BODY. Similar to male.

HEAD. Eyes smaller than in male, ratio of eye diameter to interocular space 1.0: 1.9–2.0. Antennae shorter in male, when directed backwards extending the posterior edge of pronotum, antennomere XI ca 3.6–3.7 times as long as maximum width. Length ratio of antennomeres as follows: 1.50: 1.00: 2.85:2.00: 1.70: 1.90: 1.70: 1.75: 1.70:1.75: 2.85.

PRONOTUM. Ca 1.5 times wider than length, ca 1.7 times as wide as head.

ELYTRA. Slightly wider than in male, as wide as pronotal width at humeri, length ca 2.5–2.6 times width.

OVIPOSITOR. Paraproct elongate, ca 3.1–3.2 times length of coxite, sides straight and subparallel; proctiger subtruncate.

Notes

This species is fairly common in eastern North America, found on tree bark or attracted to light. It can also be collected using Malaise or Lindgren funnel traps. Larvae develop in the moist environment beneath the bark of decaying woods ( Payne 1931; Young 1991, 2002; Majka & Pollock 2006; Ślipiński & Lawrence 2010).

Distribution

Eastern North America: USA, Canada.

Figures

Fig. 3. Habitus, dorsal view. A–B. Synchroa punctata Newman, 1838. C–D. S. melanotoides Lewis, 1895. E–F. S. chinensis Nikitsky, 1999. G–H. S. formosana Hsiao, 2015. I. S. elongatula Nikitsky, 1999. J–K. Synchroina tenuipennis Fairmaire, 1898. L. Thescelosynchroa pangu (Hsiao, Li, Liu & Pang, 2016) gen. et comb.nov.A, C, E, G, I, J, L = ♂. B, D, F, H, K = ♀. Scale bars: 5.0 mm.

Fig. 4. Elytron and abdominal ventrite V. A–F. Elytron. G–L. Abdominal ventrite V of ♂♂. — A, G. Synchroa punctata Newman, 1838. B, H. S. melanotoides Lewis, 1895. C, I. S. chinensis Nikitsky, 1999. D, J. S. formosana Hsiao, 2015.E, K. S. elongatula Nikitsky, 1999. F, L. Synchroinatenuipennis Fairmaire, 1898. Scale bars: 0.5 mm.

Fig. 5. Abdominal sternite VIII–IX and tergite VIII–X of ♂♂. A, C, E, G, I, K. Abdominal tergite VIII. B, D, F, H, J, L. Abdominal sternite VIII. M–R. Abdominal sternite IX, and fused tergite IX and X. — A–B, M. Synchroa punctata Newman, 1838. C–D, N. S. melanotoides Lewis, 1895. E–F, O.S.chinensisNikitsky, 1999.G–H,P.S.formosana Hsiao,2015.I–J,Q. S.elongatulaNikitsky,1999. K–L, R. Synchroinatenuipennis Fairmaire, 1898. Scale bars: 0.5 mm.

Fig. 6. Aedeagus. A–E. Synchroa punctata Newman, 1838. F–I. S. melanotoides Lewis, 1895. J–K. S. chinensis Nikitsky, 1999. L. S. formosana Hsiao, 2015. M–N. S. elongatula Nikitsky, 1999. O–P. Synchroina tenuipennis Fairmaire, 1898. Q–R. Thescelosynchroa pangu (Hsiao, Li, Liu & Pang, 2016) gen. et comb. nov. — A–C, F–G, J, L–M, O, Q. Dorsal view. D–E, H–I, K, N, P, R. Lateral view. Scale bars: 0.5 mm.

Tables

Table 2. Diagnostic characters among Synchroa Newman, 1838, Synchroina Fairmaire, 1898 and Thescelosynchroa gen. nov.

	Synchroa	Synchroina	Thescelosynchroa gen. nov.
Size	Large	Small	Large
	(mostly 10.0–13.0 mm) (7.0–9.0 mm)		(ca 10.0 mm)
Eyes	Large; ratio of eye	Small; ratio of eye diameter to interocular space in
	diameter to interocular	males ca 1.8–2.2
	space in males ca
	1.5–1.7
Apical maxillary	Securiform	Obliquely truncate	Securiform
palpomere
Shape of pronotum	Lateral sides strongly	Lateral sides	Lateral sides feebly arcuate
	narrowed anteriorly	somewhat rounded,
		moderately narrowed
		anteriorly
Greatest width of	As wide as elytra at humeri		Distinctly narrower than
pronotum			elytra
Surface of	Distinctly punctate	Smooth	Distinctly punctate
mesoventral cavity
Claws	Simple	Serrate	Simple
Aedeagal median	Slender and tapered, Elongate and clavate,		Elongate and clavate,
lobe	not extending the apex not extending the apex		extending from the apex of
	of the tegmen	of the tegmen	the tegmen