Stenothemus mamorui Okushima & M. Satô, 1999

Hsiao, Yun, Okushima, Yûichi & Yang, Ping-Shih, 2016, Review of the genus Stenothemus Bourgeois from Taiwan, with description of three new species (Coleoptera: Cantharidae) and additional distributional records of previously known species, Zootaxa 4117 (1), pp. 101-114 : 106-108

Stenothemus mamorui Okushima & M. Satô, 1999

Figs. 30–38

Stenothemus mamorui Okushima & M. Satô, 1999: 137 .

Type material examined. Holotype: Ƌ, Hsitsun, alt. 1050m, Fuhsing, Taoyuan Hsien, Taiwan, 19 or 24. I. 1992, M. Owada leg. ( NSMT).

Additional material examined. 4 Ƌ, 4 ♀, Lushan, Nantou, Taiwan, 14. XI. 1996, C.-C. Lo leg. ( NMNS); 1 ♀, Ssuleng, 1000m, Taoyuan Hsien, Taiwan, 13. XII. 1998, M. Owada leg. ( KURA); 1 ♀, Shikanshui, Xindian, Taipei [=New Taipei], Taiwan, 18. XII. 2004, P.-S. Hsu leg. ( NMNS); 1 Ƌ, Wulai, Taipei [=New Taipei], Taiwan, 17. I. 2006, C.-Y. Wu leg. ( NMNS); 1 ♀, Shikanshui, Taipei [=New Taipei], Taiwan, 15. XI. 2008, T.-Y. Liu leg. (NTU); 2 Ƌ, 1 ♀, Pilushenmu, Hsiulin, Hualien, Taiwan, 17. XI. 2008 – 12. I. 2009, W.-T. Yang & K.-W. Huang leg. ( NMNS); 2 Ƌ, Wulai, Taipei [=New Taipei], Taiwan, 24. XII. 2009, S.-H. Wu leg. ( NMNS); 1 Ƌ, 1 ♀, 100 Forest 17km, Tatung, Ilan, Taiwan, 6–7. XII. 2010, W.-T. Yang & H.-H. Liang leg. ( NMNS); 3 Ƌ, 2 ♀, Hualuhsi, Hsiulin, Hualien, Taiwan, 10. XII. 2009 – 4. II. 2010, W.-T. Yang & K.-W. Huang leg. ( NMNS); 1 ♀, Bilyu Sacred Tree [=Pilushenmu], Hualien, Taiwan, 16. XI. 2011 – 5. I. 2012, W.-T. Yang & K.-W. Huang leg. ( NMNS); 1 Ƌ, Fushan, Taipei [=New Taipei], Taiwan, 29. XI. 2013, Y.-T. Wang leg. (YHC).

Supplementary description. Female ( Fig. 31 ). Similar to male. Length: 10.60–13.50 mm; width: 2.50–3.30 mm. Body and pronotum wider than male; head as long as wide, eyes less protruding than male, ratio of eye diameter to interocular space 1.00:3.85; antennae shorter compared to male, extending to elytral midlength, ratio of the antennomere lengths as follows: 15.0:10.0:12.5:19.0:19.5:18.5:19.0:18.0:16.5:15:16.0.

Pronotum about 1.40 times as wide as head, about 0.90 times as long as wide. Elytra collectively about 1.40 times as wide as pronotum, about 3.35 times as long as wide. Abdominal ventrite VII ( Fig. 37 ) with lateral margins rounded, posterior margin subtruncate laterally, with broad, dark brown triangular protuberance medially along posterior margin.

Female genitalia ( Fig. 38 ) with vagina stout, rounded, with distinct folds on the surface; diverticulum thin and slightly spiralling, much longer than spermathecal duct; spermatheca with a thin, spiral and very long tube, much longer than diverticulum; accessory gland thin, about as long as diverticulum.

Diagnosis. The shape of abdominal ventrite VII of the female of S. mamorui is similar to that of S. taiwanus Okushima & M. Satô, 1997 and S. lupus sp. nov. The female of S. mamorui can be easily distinguished from S. taiwanus by: 1) its dark brown body, which is yellowish brown in S. taiwanus ; and 2) abdominal ventrite VII with more rounded lateral sides and darker, broader middle lobe, which is subtruncate, sinuate at both sides of posterior margin, with smaller middle lobe in S. taiwanus . From S. lupus sp. nov., it differs in: 1) its yellowish brown areas on the maxillary and labial palpomeres, antennomeres, pronotum, elytra, legs, prosternum, meso-, metaventrite, and abdomen, which is light brown in S. lupus ; 2) more arcuate lateral sides of pronotum, which is feebly arcuate, nearly straight in S. lupus ; 3) abdominal ventrite VII without a V-shaped dark area densely punctate; and 4) female genitalia with broader vagina, shorter diverticulum and accessory gland, and longer spermatheca.

Notes. In some specimens from various localities, the body and legs are mostly yellowish brown and the dark markings on the pronotum are indistinct ( Fig. 32 ), while some are uniformly blackish brown ( Fig. 33 ). In addition, during our study, the inner sac of male genitalia was also examined. Inner sac is about 1.35 times longer than tegmen, lengthened ventrally in apical half, obtuse apically; surface with rounded process near the apex of ventral processes ventrally and pair of horn-shaped processes near the apex of inner sac dorsally ( Figs. 34–36 ), though the inner sac of this species was described as short and stout in the original description (Okushima & Satô 1999). The inner sac of this species is observed rolled up in the basal part of laterophyses in natural condition, so it is possibly not everted completely in the holotype.

Figures

FIGURES 18 – 33. Habitus, dorsal view. 18 – 20. Stenothemus owadai Okushima & M. Satô, 1997; 21 – 22. S. seediq Hsiao, 2015; 23 – 25. S. cou Hsiao, 2015; 26 – 27. S. wittmeri Okushima & M. Satô, 1999; 28 – 29. S. taiwanus Okushima & M. Satô, 1997; 30 – 33. S. mamorui Okushima & M. Satô, 1999. Holotypes: 18, 21, 23, 26, 28, 30; Paratypes: 22, 24 – 25; Non-type specimens: 19 – 20, 27, 29, 31 – 33; Males: 18, 21, 23 – 24, 26, 28, 30, 32 – 33; Females: 19 – 20, 22, 25, 27, 29, 31. Scale bars = 5.0 mm.

FIGURES 34 – 38. Stenothemus mamorui Okushima & M. Satô, 1999. 34 – 36. Inner sac. 34. Ventral view; 35. Lateral view; 36. Dorsal view; 37. Abdominal ventrite VII of female; 38. Female genitalia. Scale bars for Figs. 34 – 37 = 0.5 mm; Scale bar for Fig. 38 = 1.0 mm.