Sanganus jenseni Distant, 1909

Sanganus jenseni Distant, 1909 View in CoL

Fig. 1B

Sanganus jenseni Distant, 1909:389 , pl. X, fig. 6 (spec.nov., description).

Sanganus jenseni : Kirkaldy (1909): 371 (catalogue).

Sanganus jenseni : Blöte (1945): 307 (listed, distribution). Sanganus jenseni : Kumar & Ghauri (1970):19-20, 26, figs. 69-70, 108 (key, Ƌ and ♀ genitalia).

Sanganus jenseni : Rolston et al. (1993): 75 (catalogue).

Type material examined. Holotype Ƌ: ( BMNH): “Type [printed, round white label with red margin] / Sanga Sanga, E. Borneo, H.D. Jensen, 1907 - 203 [printed] / Sanganus jenseni , type Dist. [handwritten]” [ Indonesia, Borneo, East Kalimantan Province, Samarinda, Sangasanga-dalam ]. Antennae, fore tibiae and tarsi, left mid leg, right mid tibia and tarsus, left hind tibia (partly) and tarsus, distal segments of right hind tarsus missing (basal tarsal segment present). Needle pinned through scutellum and mesosternum, to the right of the midline. The specimen has been re-pinned thus leaving an extra hole through the scutellum. Genital capsule, aedeagus and left paramere dissected, conserved in a glass vial. Remark: The type label was most probably added by Kumar, who studied the specimen .

Additional material examined. 2 ƋƋ: MNHN (1 ex.): “Museum Paris, Bornéo Sept., Pontianak, R. Oberthur 1897 / 367 / Museum Paris, MNHN ( EH), 3713 [printed]” [ Indonesia, Borneo Island, West Kalimantan, City or Sultanate of Pontianak] . – cPHM (1 ex.): Malaysia, Peninsular Malaysia, Pahang State, Cameron Highlands ; 15 March 2002 [Genitalia dissected, mounted on card] . 35♀♀: MNHN (1 ex.): “Museum Paris, Bornéo, Chaper 1408-91 / 367 / Museum Paris, MNHN(EH), 3712 [printed]” [Indonesia or Malaysia, Borneo Island; 14 Aug. 1891; leg. M. Chaper] . – ZMUA (8 ex.): “Noesa Kambangan, Java, Drescher [printed], 1.1917 [handwritten] / coll. Dr. D. Mac Gillavry [printed] / Sanganus cf. jenseni Dist. , det. H.J.M.G. 1935 [handwritten]” [ Indonesia, Java, Central Java Province, Nusa Kambangan Island; leg. F.C. Drescher] . – “coll. Zoölogisch Museum, acq. 1938 / Oost-Borneo, Sangasanga-dalem [printed]” (3 ex.) [ Indonesia, Borneo Island, East Kalimantan Province, Samarinda, Sangasanga-dalam ; before 1939] . – “1936 don., Kolon. Inst., Patria ignota [printed]” (2 ex.) [unknown locality; before 1937] . – “Sumatra, Alb. de Vries [handwritten] / Museum Natura Artis Magistra [printed]” [ Indonesia, Sumatra; undated] . – “Indonesia, Centr. Sumatra, Badjubang, 1°48'S 103°19'E, 1956-1957, H.F. Jansen [printed]” [ Indonesia, Sumatra, Jambi Province, Bajubang ] GoogleMaps . – ZSM (2 ♀♀): “Sumatra, Tinggi Raja III, 350-400m, Deli Serdang, 19.IX.1995, leg. E. Diehl [printed] / Sanganus jenseni Distant ♀, 1909 [handwritten], det. Arnold 2007 [printed] /yellow confetti” [ Indonesia, Sumatra, North Sumatra Province, Deli Serdang Regency, Medan ] . – “ Malaysia, Sabah, North Borneo, District Ranau, Poring Hot Spring , LF, Poring Lodge, 06°02'35N / 116°42'19E, ca. 650 müNN, leg. 14.- 16.V.2002, T. Kothe [printed] / Sanganus jenseni Distant ♀, 1909 [handwritten], det. Arnold 2007 [printed] / yellow confetti / Zoologische Staatssammlung München [printed]” GoogleMaps . – cPHM (18 ex.): Malaysia, Peninsular Malaysia, Pahang State, Cameron Highlands , 15 March 2002 (4 ex.), Sept. 2002 (1 ex.), 16 Dec. 2005, Sept. 2006 (2 ex.), 16 Dec. 2006 (6 ex.) . – Malaysia, Peninsular Malaysia, Perak State, Batang Pedang District, Tapah , Dec. 2005 (5 ex.) . – cHGK (6 ex.): Indonesia, Borneo Island, Kalimantan, Sept. 2007 (5 ex.), undated (1 ex.) .

Redescription

Colouration. Dorsal surface of dried specimens ochreous, dorsal laterotergites of connexivum and ventral surface dark brown.

Head. Mandibular plates more slender, laterally nearly straight; distally narrowly rounded ( Fig. 2 B). Antenna with first and second segment obscure, third and fourth segment ochreous ( Fig. 3 B).

Pronotum. Lateral margins concolourous, in most specimens considerably convex, anteriorly diverging ( Fig. 4 B, for character variability see Fig. 4.2 B); obscure, coarse punctures more numerous than in S. westwoodii ( Fig. 4.1 B); humeral angles of pronotum anteriorly surpassing head.

Scutellum ( Fig. 5 B) with smooth surface; punctures dark brown to black, larger and slightly less numerous; distal tongue yellow, smooth, impunctate.

Hemelytra ( Fig. 6 B) as in S. westwoodii , but punctures more prominent.

Sternum. Metasternal carina only posteriorly developed, not sulcate ( Fig. 7 B).

Metathoracic scent efferent system. Mesopleural evaporatorium larger than in S. westwoodii , apically widened, basally connected with posterior mesopleural margin ( Fig. 8 B).

Abdomen. Shape and size of ventral laterotergites VII typically as shown in Fig. 10B with exception of one specimen (see Fig. 10.1 B).

Male genitalia. Distal edge of pygophore gently curved, median notch less deep ( Fig. 11 B). Sensory lobe of paramere ovoid, distinctly protruding ( Fig. 12 B). Aedeagus ( Fig. 13 B) as in generic description; ventro-distally with an additional, very short median conjunctival appendage; sclerotized proximal conjunctival appendages short, distally bifid ( Fig. 13.1 B).

Female genitalia. Laterotergites IX rhomboid, lateral margins concave, sutural margins distally diverging and straight ( Fig. 14 B). Spermatheca as in generic description ( Fig. 15 B).

Measurements ( N = 3 ƋƋ, 37 ♀♀). Total body length: Ƌ 28.6-32. 3 mm (holotype 29.5 mm), ♀ 32.7-39.0 mm. Maximum body width across abdomen: Ƌ 18.4-19. 9 mm (holotype 19.1 mm), ♀ 19.8-24.7 mm. Head width: Ƌ 4.1-4.2 mm (holotype 4.1 mm), ♀ 4.0- 5.1 mm.Mean ratios of antennal segments I to IV: Ƌ 0.19: 0.62: 0.67: 1.00 (antennae of holotype missing), ♀ 0.22: 0.71: 0.70: 1.00. Maximum pronotum width: Ƌ 15.6-18.4 mm (holotype 15.6 mm), ♀ 17.2-23.3 mm. Maximum pronotum length: Ƌ 10.2-12.1 mm (holotype 9.0 mm), ♀ 9.5- 13.4 mm. Median scutellum length: Ƌ 6.0- 6.1 mm (holotype 6.0 mm), ♀ 5.4-9.3 mm. Basal scutellum width: Ƌ 9.5-10.1 mm (holotype 9.5 mm), ♀ 11.1- 14.2 mm.

Etymology. Dedicated to the collector of the holotype, H. D. Jensen.

Distribution ( Fig. 17). Rolston et al. (1993) mention Borneo, Sumatra, and New Guinea, the latter with reference to Blöte (1945), who indicated, however, “Merauke, New Guinea” with a question mark. We consider it highly unlikely that this species occurs so far east of Wallace’ s line. The currently known distribution, including the material examined, is as follows: Malaysia: Peninsular Malaysia (Pahang, Perak), Borneo (Sabah). Indonesia: Sumatra, Java, Borneo (Kalimantan). Philippines: Mindanao.

Species separation by morphometric characters ( Fig. 16). Both S. westwoodii and S. jenseni exhibit remarkable variability, in particular regarding body size, shape of pronotum, and shape of ventral laterotergites VII. Discriminant analyses of the morphometric data revealed, however, that the following variables may be used for discriminating between the two species, in addition to the morphological characteristics described above: Maximal length of pronotum and head index (i.e. ratio of head width to width of combined mandibular plates) are the most important variables in the model which classified 100 % of the specimens correctly in both sexes (S. w.: N = 19, group means = 8.23 mm and 2.65 mm, respectively; S. j.: N = 40, group means = 10.98 mm and 3.25 mm, respectively; maximal length of pronotum: F-to-remove = 26.74; head index: F-to-remove = 121.75; tolerance = 0.98).In females, the distal width of laterotergites IX and the diagonal running from the proximo-medial to the latero-distal angle of laterotergites IX are additional discriminating variables (S. w.: N = 13, group means = 2.88 mm and 1.96 mm, respectively; S. j.: N = 25, group means = 3.78 mm and 2.54 mm, respectively; diagonal: F-to-remove = 20.46; distal length: F-to-remove = 0.34; tolerance = 0.35). These results confirm the morphological findings that the mandibular plates of S. jenseni are more slender and the shape of laterotergites IX is rather rhomboid.