Leprocaulinus sulawesiense, Hennemann, 2021

Hennemann, Frank H., 2021, Stick insects of Sulawesi, Peleng and the Sula Islands, Indonesia- a review including checklists of species and descriptions of new taxa (Insecta: Phasmatodea), Zootaxa 5073 (1), pp. 1-189 : 37-41

publication ID	https://doi.org/ 10.11646/zootaxa.5073.1.1
publication LSID	lsid:zoobank.org:pub:AA3269D1-CA2F-4528-BC9D-3A4C75D05BD9
DOI	https://doi.org/10.5281/zenodo.10061672
persistent identifier	https://treatment.plazi.org/id/03DB87EE-FFD5-9D7E-FF40-5A75FD4AF2ED
treatment provided by	Plazi
scientific name	Leprocaulinus sulawesiense
status	sp. nov.

Treatment

Leprocaulinus sulawesiense n. sp.

( Figs. 16 View FIGURE 16 )

Carausius sp. , Günther, 1935: 8, 10.

Carausius immundus, Günther, 1938: 58 , 81 (in part—not the two ♀♀ from Luwu; these are L. digitatus n. sp.).

Carausius insularis (?), Hennemann, 1998: 97, pl. 1: 9–10, pl. 2: 1–4 & 7.

HT, ♀: Celebes, Latimodjong-Geb. Oeroe 800m, G. Heinrich 8.30 [ MNHU] .

PT, ♂: Celebes, Latimodjong-Geb. Oeroe 1500m, G. Heinrich VI .30 [MNHU].

PT, ♂: Tanke Salokko 1500 m; S-O. Celebes, Mengkoka-Geb., 1.1932, G. Heinrich [ MNHU] .

PT, 2 ♂♂, 1 ♀, 3 eggs: S-Sulawesi, Strasse von Rantepao nach Palopo km12 ca. 1100 m, leg. F. Hennemann 13.–18.VIII.1995 [coll. FH, No’s 0299-1 to 3, E].

PT, ♀: Indonesien, S-Sulawesi, Tanah Toraja , Rantepao 700m, leg. Gunawan X.1995 [coll. FH, No. 0299-4] .

PT, 6 ♂♂, 8 ♀♀, 1 ♀ (penultimate instar), 1 ♀ (n4): Indonesien, S-Sulawesi, Tanah Toraja Highland, leg. Tajuddin X.1995 – III.1996 [coll. FH, No’s 0299-5 to 18] .

Etymology: The name of this new species refers to the distribution on the island of Sulawesi.

Differential diagnosis: In lacking wings, ♂♂ of this new species resemble the Sulawesian L. heinrichi (Günther, 1935) , which is here transferred from the genus Carausius Stål, 1875 , and M. kaupii ( Stål, 1875) , which is here transferred from the genus Myronides Stål, 1875 . Males of L. heinrichi differ from the new species by the very distinctive green and brown colouration as well as the much more stocky habitus ( Fig. 15B View FIGURE 15 ). From L. kaupii the ♂♂ of this new species differ by having just two blunt swellings between the eyes ( Fig. 16M View FIGURE 16 ). Females are very similar to those of L. insularis talaudiensis (Günther, 1934) from the Talaud Islands but differ by the somewhat more stocky shape, more elongate and slender, almost parallel-sided head, much smaller Preopercular organ on abdominal sternum VII ( Fig. 16H View FIGURE 16 ), more deeply excavated posterior margin of the anal segment ( Fig. 16G View FIGURE 16 ), less convex subgenital plate and less angular dorsal lobe of the probasitarsi.

Description: The following descriptions are based on all specimens at hand for examination.

♀ ( Fig. 16 View FIGURE 16 ). Medium-sized for the genus (body length 125.5–147.0 mm), form fairly slender with a short median segment and only a pair of low swellings between the eyes ( Figs. 16A–B View FIGURE 16 ). Body surface unevenly tuberculose, granulose and rugulose, sculpturing variable and occasionally with scale-like swellings and excrescences on median segment and abdominal segment VI. Colour variable, ranging from pale ochre over various shades of ochraceous or greyish brown to very dark brown, more rarely dull green; often with faint darker mottling and occasionally with a pale ochre longitudinal median streak on abdominal terga VIII–X. Large tubercles of the head and thorax pale ochre to dull yellow. Genae usually with a small black postocular marking. Antennae dull ochre and sometimes with a slight reddish wash. Eyes dull ochre.

Head: Longer than wide, subcylindrical with the genae roughly parallel. Frons with two small transverse impressions between bases of antennae ( Fig. 16J View FIGURE 16 ). Between the eyes with a slightly swollen transverse area that bears two fairly low and obtuse swellings. Vertex flat and with a fine, impressed coronal line, otherwise set with a few scattered nodes and small tubercles ( Fig. 16J View FIGURE 16 ), genae usually with 2–3 obtuse nodes ( Fig. 16K View FIGURE 16 ). Eyes circular in outline, moderately projecting and their diametre contained about 2.6x in length of genae. Antennae reaching to posterior of median segment. Scapus compressed dorsoventrally, somewhat deflexed laterally with both lateral margins gently rounded and almost 2x longer than wide. Pedicellus oval in cross-section and about 2/5 the length of scapus.

Thorax: Pronotum of similar dimensions as head, rectangular in outline with the anterior portion very weakly expanded and about 1.8x longer than wide. Transverse median sulcus moderate, widely V-shaped and almost expanding over entire width of segment; anterior margin with a median pair of tubercles and some further paired tubercles on dorsal surface ( Fig. 16J View FIGURE 16 ). Mesothorax elongate, slender and about 5.5x longer than prothorax. Mesonotum with a fine longitudinal median carina and unevenly set with tubercles and nodes of variable sizes; those along the lateral margins more acute and largest. Mesopleurae with a longitudinal median row of nodes; mesosternum acutely keeled medio-longitudinally but otherwise smooth ( Fig. 16L View FIGURE 16 ). Metanotum a little less than half the length of mesonotum, about 3.7x longer than wide; sculpturing like mesonotum. Metapleurae and sternum sparsely nodulose.

Abdomen: Median segment about 1.5x longer than wide and a little less than half the length of metanotum; sculpturing alike and occasionally with a transverse scale-like crest or swelling at posterior margin. Abdomen excluding median segment somewhat longer than head and complete thorax combined; entire dorsal surface with a fine but fairly acute longitudinal median carina and irregularly tuberculose and rugulose. Segment II 1.6x longer than median segment, II–VI roughly uniform in length and width, on average some 2.8x longer than wide. Tergum VI usually somewhat swollen medially, sometimes with a pair of low swellings or occasionally with a laterally compressed, crest-like dorsal lobe ( Fig. 16B View FIGURE 16 ). VII slightly shorter and narrower than all preceding segments. Sterna sparsely tuberculose and Preopercular organ formed by a small, transverse, glossy black median tubercle some distance in front of the posterior margin of sternum VII ( Fig. 16H View FIGURE 16 ). Tergum VIII somewhat less than half the length of VII and slightly widening towards the posterior, IX shorter and almost quadrate in dorsal aspect. Anal segment longer than IX, strongly convex longitudinally and somewhat narrowing towards the posterior, the posterior margin with a small, roughly semi-circular median excavation and the outer angles obtusely angular ( Fig. 16G View FIGURE 16 ); the lateral margins slightly deflexed and angular in the basal portion ( Fig. 16F View FIGURE 16 ). Epiproct distinct, somewhat variable in length and shape, usually wider than long and projecting notably behind apex of anal segment ( Fig. 16G View FIGURE 16 ). Cerci very small, conical with the apex strongly constricted. Subgenital plate strongly keeled medio-longitudinally, convex, bulgy and more or less angular in the median portion ( Fig. 16F View FIGURE 16 ) and the posterior margin narrowed and projecting slightly beyond apex of abdomen ( Fig. 16G View FIGURE 16 ).

Legs: All moderately long and slender, the profemora slightly shorter than mesothorax, metafemora reaching about half way along abdominal segment IV and metatibiae reaching to abdominal segment VII. Anterodorsal carina of profemora moderately deflexed and more or less undulate and wavy in the basal one third ( Figs. 16J, K View FIGURE 16 ); the posteroventral carina with two small, obtuse sub-apical teeth. The dorsal carina of the protibiae strongly but almost uniformly deflexed and lamellate (occasionally slightly rounded sub-apically; Fig. 16K View FIGURE 16 )). Meso- and metafemora slender, laterally compressed and unarmed except for two small sub-apical teeth on the two outer ventral carinae. Medioventral carina moderate. Probasitarsus almost as long as remaining tarsomeres except claw combined and with the dorsal carina strongly raised and rounded ( Fig. 16K View FIGURE 16 ). Meso- and metabasitarsus slender and about as long as following three tarsomeres combined.

♂ ( Fig. 16 View FIGURE 16 ). Medium-sized for the genus (body length 81.0–105.0 mm), shape slender, apterous with a fairly short median segment and merely with a pair of low and obtusely conical swellings between the eyes ( Fig. 16C View FIGURE 16 ). Body surface very minutely and sparsely granulose. General colour ranging from dull ochre over mid to dark brown, occasionally with a slight olive wash. Apical portions of all femora and all coxae may be more or less distinctly red. Antennae greyish mid brown.

Head: Similar to ♀♀ but widest at the eyes and distinctly narrowing towards the posterior; the coronal line very distinct in the psterior portion and vertex set only with a very few low tubercles. Pair of swellings between the eyes more prominent and ranging from obtusely conical to rounded ( Fig. 16M View FIGURE 16 ). Eyes very large, prominent, projecting and their diametre contained about 1.6x in length of genae. Antennae reaching to posterior margin of abdominal segment III. Scapus compressed dorsoventrally with the lateral margins straight but slightly converging towards the base; almost 2x longer than wide. Pedicellus oval in cross-section.

Thorax: Pronotum roughly of same dimensions as head, the anterolateral angles somewhat expanded and the lateral margins slightly concave ( Fig. 16M View FIGURE 16 ). Transverse median sulcus very prominent, very weakly V-shaped and almost expanding over entire width of segment, a distinct impressed longitudinal median line present and running along entire length of segment. Tubercles just very weakly defined to obsolete and anterior margin with a small pair of median tubercles. Mesothorax very elongate and slender and just slightly widened posteriorly; about 6.6x longer than prothorax. Mesonotum with a very weak and fine longitudinal median carina and mesosternum weakly tectinate longitudinally. Metanotum about 2/5 the length of metanotum, surface alike.

Abdomen: Median segment a little less than half the length of metanotum, roughly 3x longer than wide and gently narrowed medially. Segment II 1.3x longer than median segment and very slightly longer than all following segments, II–VII slightly gradually decreasing in length with VII only about 3/5 the length of II. II–V on average about 5x longer than wide, VII only about 3.5x longer than wide; II–VII uniform in width and all terga with a very fine and indistinct longitudinal median line. Tergum VIII roughly half the length of VII and gently widening towards the posterior, IX shorter and narrowed towards the posterior; medio-longitudinal carina more distinct than on preceding terga. Anal segment strongly tectiform and split to form two movable hemi-terga ( Fig. 16E View FIGURE 16 ); these broad and angular in lateral aspect ( Fig. 16D View FIGURE 16 ) with the lower angle roughly at 80° and the interior surface of set with several minute denticles ( Fig. 16E View FIGURE 16 ). Cerci small, conical, slightly compressed laterally and slightly projecting beyond apex of anal segment. Poculum fairly small, moderately convex and cup-shaped, bluntly angular in lateral aspect with the posterior half obtusely carinate medio-longitudinally; the posterior margin declining in lateral aspect, bi-labiate and weakly indented medially and just not reaching posterior margin of tergum IX.

Legs: All long, slender and unarmed except for 2 small sub-apical denticles on the two outer ventral carinae of the femora. Profemora a little shorter than mesothorax, metafemora reaching about half way along abdominal segment IV and metatibiae roughly reaching to apex of abdomen. Basitarsi slender, very elongate and at least equal in length to remaining tarsomeres combined.

Eggs ( Figs 16N–O View FIGURE 16 ): A description in German and sketches have been presented by Hennemann (1998: 97, fig. 5) but a detailed English description and new illustrations are here provided. The three eggs at hand were laid by the ♀ from near Rantepao (coll. FH No. 0299-1) and thus are fully developed. Two of these eggs hatched, but the nymphs refused all alternative food plants offered.

Small, ovoid, 1.4x longer than wide, higher than wide and oval in cross-section. The anterior portion very slightly narrowed and the polar-area very weakly conical in centre. Entire surface of chorion very minutely granulose and appearing velvety to the naked eye. Micropylar plate about 2/3 the length of capsule, elongate with the anterior half roughly parallel-sided and the posterior half expanded and club-shaped; polar end with a very slight median indention. Micropylar cup a small node some distance off the polar end and roughly in centre of the expanded posterior portion. Median line very indistinct and not reaching to polar area. Operculum slightly oval in outline, convex and with a large, knob-like capitulum on a short stalk in centre; capitulum with a central hollow. General colour of capsule reddish mid brown irregularly flecked with ochre. Anterior margin and micropylar plate ochre. Operculum reddish brown and capitulum dark brown. Measurements [mm]: Length including capitulum 3.2, length 2.7–2.8, width 1.9, height 2.1–2.2, length of micropylar plate 1.8.

Variability: As usual for many members of the subfamily Lonchodinae , much less intraspecific morphological variability is seen in ♂♂. These merely show variability in size and colouration. The two ♂♂ from near Rantepao in the first authors collection (coll. FH No’s 0299-2 & 3) have the coxae and apex of all femora distinctively red, while the femora are plain or just with a very slight reddish wash at the apex in all other specimens at hand. In addition to size and colouration, ♀♀ in contrast also vary in the degree of body granulation, size of the cephalic pair of swellings and length of the epiproct and subgenital plate. The subgenital plate either hardly reaches the apex of the epiproct or it slightly projects beyond the epiproct. The ♀ from near Rantepao in the authors personal collection (coll. FH No. 0299-1, Fig. 16B View FIGURE 16 ) has a large, transverse and scale-like swelling at the posterior margin of the median segment and a prominent, laterally compressed, crest-like lobe on abdominal tergum VI. These have been illustrated by Hennemann (1998: 99, pl. 2: 1).

Comments: There has previously been some confusion about the identity of this Sulawesian taxon. Günther (1935: 8) was unsure about the identity of the ♀ and ♂ from Uru in the collection of MNHU and referred to them as “ Carausius spec. ”. The three specimens from Bua Karaeng and Luwu in NHMB are conspecific and were referred to as Carausius immundus Brunner v. Wattenwyl, 1907 by Günther (1938: 81). Also Hennemann (1998: 97) was in doubt about the identity of these specimens and further conspecific material. Having compared these to the typespecimens of C. immundus from Sumatra and Java in the collection of NHMW, Hennemann stated these Sulawesian examples were obviously a distinct species and with doubt listed them as “ Carausius insularis ( Kirby, 1896) ?”. Hennemann (1998) provided illustrations of both sexes and also presented a first description and illustration of the previously unknown eggs ( Hennemann, 1998: 102, Fig. 5 View FIGURE 5 ). Further detailed examination of the Sulawesi material has now proven this to represent an as yet undescribed species.

Distribution: Apparently widely distributed throughout the southern half of Sulawesi. S-Sulawesi, Prov. Sulawesi Selatan, Gunung Latimojong, Rantemario, Uru 800 m [MNHU]; S-Sulawesi, Prov. Sulawesi Selatan, Ran-tepao Palopo km12, ca. 1100 m [coll. FH]; S-Sulawesi, Prov. Sulawesi Selatan, Tana Toraja, 700 m [coll. FH]; SE-Sulawesi, Mengkoka Mountains, Gunung Tanke Salokko [MNHU].

Genus Mnesilochus Stål, 1877

( Figs. 17–18 View FIGURE 17 View FIGURE 18 )

Type-species: Mnesilochus capreolus Stål, 1877: 39 , by subsequent designation of Kirby, 1904: 320.

Comments: This genus is distributed in Borneo, Palawan and the Philippines and the author is aware of an as yet undescribed species that occurs on Sangihe Island north of Sulawesi. The two species here described are the first records of the genus from Sulawesi.

Mnesilochus has been removed from synonymy with Carausius Stål, 1875 and reinstated as a valid genus by Hennemann & Conle (2007: 66). These authors and Seow-Choen (2016: 279) have attempted a clear separation from the very similar Hermagoras Stål, 1875 but morphological characters in the insects are scarce and merely include whether the mesosternum is keeled medio-longitudinally ( Hermagoras ) or not ( Mnesilochus ) and whether the eggs are round to ovoid with a rounded polar area ( Hermagoras ) or more or less laterally compressed and have a polar mound ( Mnesilochus ). The distinction presented by Seow-Choen (2016: 279) includes an erroneous character and thus deserves clarification. In addition to the morphology of the mesosternum, the author stated in the key to Bornean genera of Lonchodinae : Lonchodinae “ Postero-dorsal carina of profemur curved forwards, lamellate and may be foliaceous covering totally or partially antero-dorsal carina which is generally straight ” for Hermagoras and “ Postero-dorsal carina of profemor nut usually lobes ” for Mnesilochus ( Seow-Choen, 2016: 279) . This distinction does not hold true because Seow-Choen misinterpreted the anterodorsal carina as the posterodorsal carina and the anteroventral carina as the anterodorsal carina. Actually, the morphology of the profemur is basically identical in these two genera and remarkable in that the medioventral carina is very prominently developed, lamellate and strongly displaced towards the interior/anterior, resulting in that the anteroventral carina is strongly shifted inwards and upwards and notably approaches the anterodorsal carina. The anterodorsal carina (not the posteroventral carina as wrongly stated by Seow-Choen) is much expanded, lamellate and curved forwards to partly or completely cover the anteroventral carina in dorsal aspect. The posterodorsal carina in fact is very indistinct and not raised at all, being low and merely represented as an obtuse keel or ridge.