Arumatia aramatia Ghirotto, 2022

Ghirotto, Victor Morais, Crispino, Edgar Blois, Engelking, Phillip Watzke, Neves, Pedro Alvaro Barbosa Aguiar, Góis, Júlia de & Chiquetto-Machado, Pedro Ivo, 2022, Arumatia, a new genus of Diapheromerinae stick insects (Insecta, Phasmatodea) from Brazil, with the description of five new species and a reassessment of species misplaced in Australian genera, European Journal of Taxonomy 827 (827), pp. 1-85 : 42-53

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Arumatia aramatia Ghirotto

gen. et sp. nov.

Arumatia aramatia Ghirotto gen. et sp. nov.

Figs 25–33 View Fig View Fig View Fig View Fig View Fig View Fig View Fig View Fig View Fig , 43 View Fig , 52 View Fig , 53F View Fig



From Arumatia dubia gen. et comb. nov. and A. fulgens gen. et comb. nov. it differs by the more elongate head, the shorter median segment in relation to the metanotum, the longer terga VIII–X, the round posterior margin of tergum X, the slightly longer subgenital plate, the presence of a praeopercular organ and additionally from A. dubia the longer gonapophyses VIII. From A. anyami gen. et sp. nov. it differs by the more elongate head, the longer median segment in relation to the metanotum, the presence of stouter and spiniform setae at the apex of the carinae of the tibiae, the round posterior margin of tergum X, the slightly shorter subgenital plate, the presence of a praeopercular organ, the longer gonoplac and gonapophyses IX and shorter gonapophyses VIII. From A. crassicercata gen. et sp. nov. it differs by the more elongate head, the shorter median segment in relation to the metanotum, round posterior margin of tergum X, the longer cerci, and the longer gonapophyses IX. From A. motenata gen. et sp. nov. and A. diamante gen. et sp. nov. it differs by the less elongate head, the longer median segment in relation to the metanotum, the presence of stronger spiniform setae on the carinae of tarsi and on the apex of mid tibiae, the absence of an apical sessile spine on the apex of the ventral, antero- and posteroventral carinae of the tibiae, the longer cerci and subgenital plate and shorter gonapophyses VIII.


From Arumatia motenata gen. et sp. nov., the only other species with a known male, it differs by the head with convex sides in dorsal view rather than parallel to concave, the presence of one to few stouter spiniform setae at the end of all carinae, the absence of an apical sessile spine on the apex of ventral, antero- and posteroventral carinae of the tibiae, tergum IX longer than X, poculum elongate and conical, pointed in lateral view, tergum X without lateral expansions, and thorn pads restricted to the ventral area of the posterior margin of tergum X.


Eggs of Arumatia aramatia gen. et sp. nov. can be differentiated from known eggs of all other species by the fewer distinct, slightly sinuous ridges of the capitulum forming a shape resembling a turtle shell as well as the large and not constricted opercular collar which is shared only with the eggs of A. diamante gen. et sp. nov.


This species is named in reference to Aramatiá, a variant of the indigenous name for stick insects in Brazil, Arumatiá , which inspired the name of the new genus of which this is the type-species. To be treated as a noun in apposition.

Material examined

Holotype BRAZIL • ♀; Tocantins, Porto Nacional, Luzimangues district, at margins of Ribeirão Santa Luzia; 10°03′40.1″ S, 48°25′10.1″ W; 15 Aug. 2002; D. Pavan and J.P. Silva leg.; “vegetação fechada” [dense vegetation]; campanha VII; gride C; MZUSP 1352 View Materials . GoogleMaps

Paratype BRAZIL • 1 ♂; same collection data as for holotype; 6–14 Dec. 2002; campanha IX; MZUSP 1322 View Materials GoogleMaps .


Eggs were obtained from inside the abdomen of the only known female and might differ in some details from laid eggs. For comparison, analysis of eggs of Arumatia dubia gen. et comb. nov. extracted from the same region of the abdomen revealed that in this species the capitulum and micropylar plate were already formed but the whitish dorsal stains were not present and the texture of the capsule was sometimes smooth, still not formed.


Female (holotype, MZUSP 1352)

MEASUREMENTS (in mm). Body (without cerci) 86.1, head 5.0, antennae at least 12.0, pronotum 3.3, mesonotum 22.6, metanotum 7.0, median segment 5.2, abdomen (excluding median segment) 43.0, cercus 5.8, profemur 21.8, protibia 23.3, mesofemur 15.0, mesotibia 15.8, metafemur 20.0, metatibia at least 22.2.

COLOUR ( Fig. 25 View Fig ). Known only from aged specimens preserved in alcohol. Entirely brown to yellowish beige, lighter in the legs. Body with scattered dark sprinkled stains and dorsal longitudinal medial dark line running across mesonotum, menatonum, median segment and sternum II.

HEAD ( Fig. 26 View Fig ). Fairly elongate, smooth with sparse setae mostly on dorsal region, vertex flat but very gently convex at posterior margin to fit underneath the pronotum, frontal convexity developed, frontal suture round ( Fig. 26A–B View Fig ). Eyes small, slightly elongate, approximately 0.2 × as long as head. Cervix covering significantly more than half of head, cervical sclerites developed, gula bearing setae and covering less than half of cervix ( Fig. 26C View Fig ). Subgena fairly narrow with posterior projection ca height of middle of eye. Submentum narrow and slightly curved towards posterior, mentum simple and prementum somewhat wide. Glossa elongate and rounded, paraglossa larger, roundly falcate and reaching labrum. Lacinia with three distal teeth, one large medially and two smaller laterally, mesal edge bearing around 6 large setae. Galea slightly elongate, roundly elliptical, bearing long setae, apically with dense semicircular band of hairy and large microtrichia. Galealobulus present, small, widely round and basally fused to galea. Maxillary palpal segments cylindrical, labial slightly widened. Clypeus wide, approximately trapezoidal. Labrum strongly notched anteromedially, asymmetric. Antennae filiform, broken. Scapus ca 1.8 × as long as wide, basally and apically slightly constricted in dorsal view, slightly compressed dorsoventrally. Pedicellus subglobose, large and more than half length of scapus ( Fig. 26A View Fig ).

THORAX ( Figs 25–26 View Fig View Fig , 27A View Fig ). Smooth with scattered setae. Pronotum longer than wide, slightly constricted pre-medially and slightly wider from transverse sulcus towards anterior margin, fairly flat in lateral view,

transverse sulcus conspicuous and almost straight, longitudinal sulcus conspicuous and distinct. Paranota curved, slightly widened medially and longer than wide, procoxopleurite apically round and ventrally gently concave ( Fig. 26 View Fig ). Probasisternum tapering towards anterior, profurcasternum round ( Fig. 26C View Fig ). Mesothorax 4.8× as long as prothorax. Mesonotum with pair of weak lateral carinae, mesepisternum lanceolate and regularly widening posteriorly. Mesepimeron slightly elongate, pointing towards posterior and slightly exceeding end of mesothorax, mesocoxopleurite indistinct, mesofurca Y-shaped. Metathorax continuing pair of lateral carinae of mesonotum, metepisternum long and similar to mesepisternum, metepimeron extremely elongate, extending through the entire length of median segment, posteriorly

pointing and slightly exceeding end of median segment ( Fig. 27A View Fig ). Metacoxopleurite very discrete, elongate, metafurca Y-shaped. Metanotum 1.2× as long as median segment ( Fig. 27A View Fig ).

LEGS ( Figs 25 View Fig , 27B–F View Fig ). Slender. Hindlegs extending beyond epiproct, at least slightly shorter than anterior legs, midlegs distinctly shorter. Coxae smooth. Profemur with distinct basal curvature. Femora and tibiae with five carinae with few sparse setae among them ( Fig. 27B–F View Fig ). Carinae of profemora and protibiae distinctly keeled, mid and hind femora and tibiae with slightly less prominent keels. Antero- and posteroventral carinae of femora with round apical prominence. Carinae of all femora, tibiae and tarsi bearing row of short, stout setae. Last few setae of all carinae of protibiae and last five setae of ventral carinae, last three of antero- and posteroventral carinae and last two of antero- and postero-dorsal carinae of mesotibiae stouter and spiniform ( Fig. 27B–E View Fig ). Metatibia apex broken off ( Fig. 27F View Fig ). In tarsi, setae on carinae distributed across about three quarters to four fifths of length and on ventral and posteroventral carinae of probasitarsi longer and only slightly stouter while setae on ventral, antero- and posteroventral carinae of mesobasitarsi stouter (only slightly on anteroventral carinae) ( Fig. 27B–E View Fig ). Probasitarsi very elongate and significantly longer than respective following tarsomeres combined,

mesobasitarsi as long as respective following tarsomeres combined ( Fig. 27B–E View Fig ), with hairy setae restricted to apical portion on ventrolateral patches ( Fig. 27B, D View Fig ). Remaining tarsomeres with setae on ventrolateral patches in portions not covered by euplantulae. Tarsomeres I–III with a discrete dorsal round apical projection. Arolium round and broad, bearing setae dorsally. Pretarsal claws symmetrical, dorsally and outwardly bearing setae. Euplantulae well developed in all tarsomeres, composed of two symmetrical pads separated by median groove in tarsomeres I–III, of single pointing domed pad in tarsomeres IV, and of single flattened lobed pad in tarsomeres V. Euplantulae present only apically at

tarsomeres I–II, covering ca half length of tarsomeres III, covering two thirds length of tarsomeres IV and covering almost entire ventral surface of tarsomeres V ( Fig. 27B View Fig ).

ABDOMEN ( Figs 25 View Fig , 27A View Fig , 28 View Fig ). External surface as in thorax, bearing few setae across entire length. Median segment slightly shorter than metanotum ( Fig. 27A View Fig ). Combined length of segments II–X as long as combined length of head, thorax and median segment. Terga II–VII and sterna II–VIII bearing discrete lateral carinae near lateral margins. All segments longer than wide ( Fig. 25 View Fig ). Segment II ca as long as III and VII, segments III–V slightly increasing in size in relation to anterior segment, segment VI ca as long as V, tergum VII shorter than on preceding segment, and longer than VIII, terga X and IX same size, slightly shorter than VIII. Terga II–V around same width, wider than following terga, VI wider than following terga, VIII–X around same width ( Fig. 28A View Fig ). Tergum X somewhat conical in lateral view ( Fig. 28B View Fig ), in dorsal view almost parallel-sided but gently tapering towards posterior, posterior margin straight with round lateral margins ( Fig. 28A View Fig ). Epiproct domed in dorsal view, dorsoventrally flattened, distinctly prominent visible dorsally and laterally ( Fig. 28A–B View Fig ). Paraprocts elongate, posteriorly acute, straight and bearing setae on posterior margin, laterally bearing cerci, not concealing them from ventral or lateral view ( Fig. 28B–C View Fig ). Cerci extremely elongate, straight, gently laterally compressed, basally narrower fitting paraprocts, pointing to posterior, gradually tapering, slightly longer than terga IX, X and epiproct combined ( Fig. 28A–C View Fig ). Cerci bear four types of setae, shorter setae very discrete, round and not protruding. Praeopercular organ small, round, brownish and posteriorly with short longitudinal sulcus continuing across posterior margin of sternum VII ( Fig. 28B–C, F View Fig ). Subgenital plate lanceolate, fairly acute, reaching ⅔ of length of tergum X, bearing two parasagittal carinae beginning on anterior margin and running half length of segment before becoming flatter and more setose, gradually tapering towards posterior and totally covering gonapophyses and gonoplac ( Fig. 28B–C View Fig ). Gonapophyses and gonoplac flattened, dorsoventrally for gonapophyses VIII, lateroventrally for IX and laterally for

gonoplac ( Fig. 28D–E View Fig ). Gonapophyses VIII longer than IX, VIII almost reaching tergum X, IX reaching ca ¾ of length of tergum IX, VIII linear to lorate, IX conical, tapering towards posterior ( Fig. 28D–E View Fig ). Gonapophyses IX ventrally folded to fit within gonapophyses VIII. Gonangulum distinctly reduced, flat, not lobed. Gonoplac significantly elongate, widened basally, subsequently lorate, bearing setae, exceeding both gonapophyses and exceeding anterior margin of tergum X ( Fig. 28D–E View Fig ).

Male paratype (MZUSP 1322)

MEASUREMENTS (in mm). Body 56.7, head 2.7, antennae at least 15.0, pronotum 2.2, mesonotum 13.8, metanotum 5.4, median segment 4.1, abdomen (excluding median segment) 28.5, cercus 1.0, profemur -, protibia -, mesofemur 11.8, mesotibia 13.1, metafemur 16.7, metatibia 19.8.

COLOUR ( Fig. 29 View Fig ). Known only from aged specimen preserved in alcohol. Entirely dark brown to yellowish beige, lighter in legs, darker than female. Head, pronotum and mesonotum with two lateral dark lines ( Fig. 30B View Fig ).

HEAD ( Fig. 30 View Fig ). Similar to female except: eyes, scapus and pedicel larger, head slightly widening from posterior margin to behind eyes in dorsal view ( Fig. 30A View Fig ). Palpal segments larger, labial less widened.

THORAX ( Figs 29 View Fig , 31A View Fig ). Similar to female except: significantly thinner, more elongate than that of female. Mesothorax 6.6× as long as prothorax. Mesocoxopleurite larger and triangular.

LEGS ( Figs 29 View Fig , 31B–D View Fig ). Forelegs not present in paratype, the only known male of species. Similar to female except: legs longer and thinner than those of female ( Fig. 29 View Fig ). All setae generally longer than those of female ( Fig. 31B–D View Fig ). Setae on carinae of meso- and metafemora slightly sparser, longer, on carinae of meso- and metatibiae slightly longer, stouter, and apical spiniform setae of carinae of tibiae only slightly stouter than remaining setae ( Fig. 31D View Fig ). Meso- and metabasitarsi longer than respective following tarsomeres combined ( Fig. 31B–C View Fig ). Metabasitarsi with stouter setae on ventral, antero- and

posteroventral carinae, stronger on ventral carinae. Ventrolateral hairy setae of tarsomeres denser. Euplantulae shorter.

ABDOMEN ( Figs 29 View Fig , 31A View Fig , 32 View Fig ). Thinner and more elongate than that of female. Median segment anteriorly with two parasagittal ovoid stains ( Fig. 31A View Fig ), lateral carinae absent. Terga II and VI about same length, both slightly shorter than III–V, tergum VI shorter than VII, tergum VII longer than VIII, terga VIII and IX about same length, X shorter. Terga II–V about same width, tergum VI slightly shorter, tergum VII anteriorly as wide as VI and slightly widened posteriorly, tergum VIII slightly wider than VII and IX ( Fig 32A View Fig ). Tergum X wider than IX, about as long as wide, slightly widened towards posterior, sides convex in dorsal view and with posterior margin emarginate forming two round edges ( Fig. 32A View Fig ). Thorn pads at ventral area of posterior margin of tergum X bearing ca 32 small to large inwardly curved short, sclerotized teeth ( Fig. 32C View Fig ). Tergum VIII and sternum VIII separated, not fused ( Fig. 32B, D View Fig ). Sternum VIII partly fused with sternum IX, border between both sterna shown as asymmetric sulcus curving towards posterior on right side ( Fig. 32E View Fig ). Sternum IX reduced with anterior portion indistinct; only shown as poculum. Poculum reaching around ¾ length of tergum IX, due to asymmetry of sulcus poculum

shorter at right side than left side ( Fig. 32B, D View Fig ). Poculum slightly elongate, conical in lateral view, round in ventral view, posterior margin medially with wide emarginate short curvature towards anterior ( Fig. 32B, D–E View Fig ). Cerci slightly shorter than tergum X, inwardly curved, with round apex ( Fig. 32B, D–E View Fig ). Epiproct small, hidden from dorsal and lateral view ( Fig 32F View Fig ). Vomer elongate, convex, terminal hook elongate and strongly sclerotized, acute, conical, single pointed and curving upwards ( Fig. 32F View Fig ).

MALE GENITALIA ( Fig. 43 View Fig , left side). Male genitalia or phallic organ composed of dorsalmost sclerite (dorsal sclerite), wide lobe with fine granulation originating ventrally from dorsal sclerite (longitudinal lobe), and smaller and shorter lobe basally, slightly ventrally, on right side, the (right) basal lobe. Dorsal sclerite very elongate, somewhat hook-shaped, curved to left in dorsal view and penetrating body cavity. Anterior portion penetrating body narrower. Posterior portion wider, connecting to rest of genitalia, and apically further bending ventrally while continuing left curve of whole structure, basally near anterior portion very short, round projection pointing anteriorly. Longitudinal lobe bends accompanying dorsal sclerite, and forming apicalmost round lobe, small elongate and thin lobe at right side and central foldings. Longitudinal lobe basally bearing round weak internal sclerotization near dorsal sclerite ( Fig. 43E–H View Fig ). Basal lobe conical, flattened and densely granulated.

Egg ( Fig. 33 View Fig )

Egg not fully formed, retrieved from inside female holotype. Measurements in mm (N = 3): length 2.5–2.6, height 1.9, width 1.5. Relatively small, ovoid in lateral view, not constricted at opercular

collar, gently compressed laterally and ca 1.6 × as long as wide and 1.4× as long as tall ( Fig. 33A–D View Fig ). Capsule surface smooth but with finely punctuated appearance ( Fig. 33B, D View Fig ). Colour yellowish orange. Micropylar plate very elongate, occupying large area of dorsal region, with round margins and almost parallel-sided ( Fig. 33C–D View Fig ). Micropylar cup small, rounded and only slightly elevated. Median line short and of same colour and elevation as elevated margin of micropylar plate, almost reaching polar area ( Fig. 33C–D View Fig ). Opercular collar very wide, as wide as surrounding capsule, smooth with minute and delicate long bristles along edge ( Fig. 33A View Fig ). Operculum elliptical, with sinuous and somewhat radial elevations with amber texture, in shape resembling a turtle shell ( Fig. 33A, F–G View Fig ).

Distribution ( Fig. 52 View Fig )

Known only from the type locality, Luzimangues District, along Santa Luzia River, in Porto Nacional, Tocantins, Brazil. This area is in the Cerrado domain and the types were found in savannah formations ( Fig. 53F View Fig ).