Marcgraviella Souza-Dias & Desutter-Grandcolas, 2014, n. gen.
Creators: name: Souza-Dias, Pedro G. B.
name: Desutter-Grandcolas, Laure
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Orthoptera
Haglotettigoniidae
Marcgraviella

description: Marcgraviella, n. gen.
Etymology. Taxon dedicated to the German naturalist Georg Marcgrave, the first naturalist to study the fauna of Northeast Brazil in 17th century.
Type species. Marcgraviella muriciensis Souza-Dias, n. sp.
Species included. Marcgraviella muriciensis Souza-Dias n. sp., Marcgraviella christianae Desutter- Grandcolas & Souza-Dias n. sp.
Distribution. Northeastern Brazil, in Alagoas and Pernambuco States.
Diagnosis. Coloration light yellow brown, with a distinctive ivory band between the eyes on head dorsum; legs not annulated and very elongated in relation to body length (more than 2x larger). Fastigium about as wide as the scape, slightly narrowed distally; not separated from the vertex by a transverse furrow. Joint 4 of maxillary palpi the longest. TI inner tympanum, obliterate; outer tympanum lacking. TIII with 4 pairs of subapical spurs. Male. Short, narrow but not vestigial FWs, slightly coriaceous; stridulatory file in a deep FW depression; stridulum more or less complete. Metanotum with a pair of « ball-shaped », median structures, in addition to muscular insertions. Supra anal plate with two bunches of strong setae on distal margin. Male genitalia. Pseudepiphallic sclerite with phallic glands and a pair of tubular pseudepiphallic arms dorsally crossing each other in the median part of the pseudepiphallic sclerite; each arm with an opening duct on its apex; pseudepiphallic parameres well developed, with at least two elongated and membranous lobes, inflatable, and partially sclerotized. Female. Larger than male; general coloration medium to dark brown; FWs vestigial, reduced to a small scale. Female genitalia. Copulatory papilla drop-shaped, sclerotized.
Description. Body small, slender; legs, thin and elongated, the hind femora with a distinctly thinner apical part of about 1/3 of their whole length (Fig. 1 N). General coloration light brown. Head small. Fastigium a bit narrowed toward the apex (Figs 1 C, 4A); very slightly furrowed longitudinally; slightly lower than the vertex, from which it is not separated by a transverse furrow (Figs 1 C, F, 4B); 3 ocelli present, the distance between the median and one lateral ocelli about three fourth that between the lateral ocelli (Figs 1 C, 4A). Eyes large and moderately prominent (Figs 1 C, 4A); separated from subgenual suture by a distance about one third eye length (Figs 1 E, 4A). Scapes longer than wide (Figs 1 C, 4A). Maxillary palpi very long and thin (Fig. 1 E, F); joint 4 the longest; joint 5 slightly longer than joint 3, only slightly widened; distal portion of joint 5 curved (Fig. 1 E, F). Pronotum transverse; DD cephalic margin slightly convex; DD caudal margin well concave (Figs 1 C, 4A); LL ventro-cephalic angle curved, with ventral margin ascending arcuate into the caudal margin and ventro-caudal angle not distinct (Figs 1 D, 4B). TI bearing only the internal tympanum, small and oblitered (Fig. 1 F); with 2, ventral, apical spurs. TII with 4 apical spurs, the ventrals twice as long as the dorsals. TIII longer than FIII, with 4 pairs of alternate subapical spurs (Fig. 1 O); strong serrulation between and above subapical spurs, except between inner subapical spurs 1 and 2; 3 inner and 3 outer apical spurs, the median the longest on both sides; median inner spur the longest, less than half basitarsomere III length. Basitarsomeres III very elongate; with two rows of spines (Fig. 1 O). Serrulation of TIII and basitarsomeres III made of long, thin dorsal spines (Fig. 1 O).
Male. Metanotum with two broad humps on its antero-lateral borders (muscular insertions) and two small, median rounded projections, without setae and apparent pores, but with irregular surfaces (problably glandular); metanotal distal margin raised and thick (Figs 1 G, 4C). FWs covering part of the abdomen, up to tergite 5 (M. muriciensis Souza-Dias, n. sp.) or covering almost the whole abdomen (M. christianae Desutter-Grandcolas & Souza-Dias, n. sp. (Fig. 4 D), not truncated distally; slightly coriaceous; stridulatory vein present, located in a deep depression of right FW (Figs 2 D, 4D, 5E), with few, widely set teeth; left forewing partly thin dorsally, with a file made of very few teeth on the outer part of the stridulatory vein; harp and mirror present, but not clearly separated from surrounding venation (Figs. 2 D, 4D, 5E); chords 1 and 2 fused very distally, at about one third of chord 3 length (Figs. 2 D, 5E); CuP absent, but FW inflated along CuP normal location; MP and CuA widely separated over their whole length; separation between dorsal and lateral fields made by MP (Figs. 2 D, 5E). Lateral field: MA and MP very strong, parallel over their whole length; R weaker than the media veins, with 5-6 irregular, faint bifurcations, and fused with MA distally (Fig. 5 F). Hindwings absent. Supra anal plate without extended angles distally, but with two bunches of long and thick setae on distal margin (Figs 1 H, 4E). Subgenital plate short, wider than long; deeply furrowed longitudinally, and indented apically (Figs 1 J, 4F).
Male genitalia. Pseudepiphallic sclerite with phallic glands and two dorsal tubular pseudepiphallic arms dorsally crossing each other in the median part of the pseudepiphallic sclerite; each arm with an opening duct on its apex. Pseudepiphallic parameres well developed, with membranous inflatable areas, and otherwise partially sclerotized; the sclerotization concentrated on its ventral part. Endophallic sclerite located in the deep of a median ventral slit, with low sclerotization and extending until the basis of the pseudepiphallic parameres; endophallic apodeme present.
Female. Larger than male (Fig. 1 B); general coloration darker than male (Fig. 1 B). Tegmina very reduced, vestigial, not reaching the half of metanotum and not overlapping. Supra anal plate same as male (Fig. 1 I). Subgenital plate small, deeply indented apically (Fig. 1 K). Ovipositor as in Figs. 1 L, M.
Female genitalia. Copulatory papilla drop-shaped, sclerotized, as in Figs. 3 C–E.
Phylogenetic relationships. Marcgraviella, n. gen. belongs to a group of genera including Aracamby, Cacruzia, Izecksohniella, Marliella, and Vanzoliniella, based on the structure of male genitalia. This cluster of genera is characterized by the phallic glands within the pseudepiphallic sclerite, the development of a pair of tubular pseudepiphallic arms associated to these glands and the partly membranous and sclerotized pseudepiphallic parameres. Using wide scale observations of male genitalia, one of us (PSD) proposed to name this group of genera, the Aracambiae Souza-Dias. Phylogenetic studies, based on morphological and molecular characters, are presently undertaken to define a wide evolutionary frame to study the evolution of genitalia in this clade.
The occurrence of distal projections arising from the pseudepiphallic sclerite, the pseudepiphallic arms (referred as pseudepiphallic spines by de Mello & de Andrade 2003; Bolfarini & de Mello 2012; de Mello et al. 2013), is widespread within the group C of Luzarinae. While in the Aracambiae group they are tubular and connected to phallic glands, in more distant related genera as Eidmanacris, Strinatia, Endophallusia de Mello, 1990, Ottedana de Mello & de Andrade, 2003, Adenopygus Bolfarini & de Mello, 2012, and Bambuina de Mello, Horta & Bolfarini, 2013, they have different patterns, usually being enlarged toward the apex, laminar or rodshaped, and not linked to phallic glands (de Mello & de Andrade 2003; de Mello et al. 2013).
Among the Aracambiae group, other general morphology characters are shared as the small and slender body, elongation of legs, mainly the posterior, and the reduction of male FWs. The stridulatory vein is present in Aracamby, Cacruzia, Vanzoliniella, and Marcgraviella n. gen. and absent in Izecksohniella and Marliella. Marcgraviella n. gen. shares with Cacruzia and Vanzoliniella the shape and aspect of the FWs, being thin, hard, and not strongly coriaceous; also, tympanum is present on the inner side of foretibia only. The presence of rounded projections in the metanotum is shared by Marcgraviella n. gen., Cacruzia, and Marliella, and the presence of vestigial tegmina in adult females is shared by all genera except Cacruzia.
Regarding the general morphology, the genera of the Aracambiae group are very similar. These genera can only be separated using a combination of general morphology and male genitalia characters, with the latter being the main character to define and separate the genera (see key below).
The monophyly of Marcgraviella n. gen. can be ascertained by the pattern of the pseudepiphallic parameres, with at least two well developed and partially sclerotized lobes, with membranous, inflatable areas.
description: Published as part of Souza-Dias, Pedro G. B. & Desutter-Grandcolas, Laure, 2014, A new genus and two new species of Luzarinae cricket from the Atlantic Forest of Northeast Brazil (Orthoptera, Grylloidea), pp. 498-512 in Zootaxa 3872 (5) on pages 500-502, DOI: 10.11646/zootaxa.3872.5.4, http://zenodo.org/record/230507