Melidia adfinia, Hemp & Heller, 2019

Hemp, Claudia & Heller, Klaus-Gerhard, 2019, Orthoptera (Tettigoniidae and Acridoidea) from Miombo woodlands of Central Tanzania with the description of new taxa, Zootaxa 4671 (2), pp. 151-194 : 182-184

Melidia adfinia n. sp. Hemp C.

( Fig. 35 A , 36 D , 37 A , 39 G, H )

Holotype. Male. Miombo woodlands on hill near Gulwe, Mpwapwa District , Dodoma Region, in herb vegetation along forest edge, 1000 m, March 2018 . Paratypes. 2 males, 4 females, same data as holotype . 1 male, Changalawe Hill, Miombo woodlands, nr road A104, in herb vegetation, March 2015. Depository: Collection C. Hemp.

Description. Male. General colour as for genus, predominantly green with dark brown marking around stridulatory area. Antennae and head. Fastigium typical for genus. Antenna little longer than body length, thin and whitish. Eyes oval, prominent. Pronotum and thorax. Pronotum without lateral carinae, surface smooth and matt. Posterior margin slightly incurved, posterior margin also incurved with lateral edges elevated. Stridulatory file divided into two parts; part at inner side of tegmen with few broad large teeth, parted from proximal part by gap. Remaining stridulatory file with numerous fine teeth decreasing gradually in size, about 2.2 mm long and slightly curved along length ( Fig. 36 D ). On right tegmen comparatively large and almost round mirror ( Fig. 30 A ). Abdomen and legs. Fore coxae with small and straight spine. Fore and mid femora with 1–2 ventral spinules near joint of tibiae. Hind femora with 1–4 ventral spinules near apex. Fore and mid tibiae with pair of spurs and few small spinules along length. Hind tibiae almost tri-angular in diameter, with 3–4 rows of of spinules along length; apices with each three tiny spurs at each side. Veins Sc and R separate from base, running almost in parallel and diverging only at their very ends. Male tenth abdominal tergite broad, produced posteriorly and down-curved ( Fig. 38 G ). Cerci elongated, round till about midway, then abruptly inwardly curved, forming a three-ridged laterally compressed structure ( Fig. 38 G ). Male subgenital plate elongated, posterior half to third deeply divided and forming two lobes ( Fig. 38 H ), without styli.

Female. Similar to male but stouter. Most female specimens with number of small tiny black dots on tegmina ( Fig. 35 A ). On each tegmen brown marking at base and one small brown patch at inner margin at about half length of tegmen. The brown patch midway on the tegmina is lacking in males. Subgenital plate laterally elongated sheathing the ovipositor ( Fig. 39 A ). Ovipositor comparatively short, strongly up-curved, with fine teeth.

Measurements, males (mm) (N=3). Total length of body 16.4–17.2; Median length of pronotum 2.8–3.0; Length of hind femur 14.0–16.1; Length of elytra 20.7–22.3.

Measurements, females (mm) (N=5). Total length of body 15.6–16.8; Median length of pronotum 3.5–3.7; Length of hind femur 16.1–18.3; Length of elytra 22.4–25.6; Length of ovipositor 7.0–7.2.

Diagnosis. From their outer appearance Melidia species are quite similar. Differences are found in the length of the subgenital plate and how deeply it is lobed (compare Figs. 38 B, D, F and H ), in the length and shape of the male cerci (compare Fig. 38. A, C, E and G ) and the l0 th abdominal tergite. The male of M. kenyensis is not known. The 10 th abdominal tergites in M. claudiae , M. brunneri and M. laminata are almost square with a more or less straight posterior margin that is slightly down-curved. In M. adfinia n. sp. the posterior margin is more produced and more strongly down-curved than in the other species. The cerci of M. adfinia n. sp. are abruptly inwardly curved forming a three-ridged lance, the cerci of the other species are continuous and not differentiated into two morphologically differently shaped parts. M. adfinia n. sp. also has a completely different stridulatory file not found in any other Melidia species. While in M. laminata the stridulatory file consists of few, large and widely spaced teeth ( Fig. 36 A, B ; note the differences of the specimen from Wajir, Kenya, the area from which the species was described, and the specimen coming from around Kilimanjaro), in M. brunneri from Mahonaland, Salisbury, southern Africa ( Fig. 36 C ) the inner part of the file consists of small teeth while the other half of the file consists of large, widely set teeth. In M. adfinia n. sp. the inner part of the stridulatory file consists of few large and widely set teeth while the other part has tiny, very densely set teeth, both parts are separated by a gap ( Fig. 36 D ).

Females of all known species have differently shaped subgenital plates ( Fig. 39 and 40 ). M. adfinia n. sp. is the only species with a deeply divided subgenital plate, sheathing the ovipositor ( Fig. 39 A ). The subgenital plate of M. kenyensis has a cushion-like appearance ( Fig. 39 B ) while in M. brunneri two broad, leaf-like lobes are formed. There are slight morphological differences between female specimens of M. laminata coming from central and north-east Kenya (lacking lateral flanges, arrow in Fig. 39 C ) while the subgenital plate of specimens from northern Tanzania are broad with two lateral well developed flanges (arrow in Fig. 39 D ). Acoustical and molecular studies have to be conducted to clarify the status of M. laminata populations from Kenya and Tanzania.

Habitat. Herbaceous vegetation along the edges and on clearings of Miombo woodlands.

Distribution. Central Tanzania, Dodoma Region.

Etymology. From Latin— adfinia ; related, since this new species resembles M. laminata from its general appearance.

Figures

FIGURE 30. Kefalia laeta n. sp. from Mingali Forest Reserve A. Male B. Mating pair C, D. Different colour forms of female.

FIGURE 35. Melidia adfinia n. sp. female (A) and females of M. laminata from the foothills of the West Usambara Mountains (B) and the South Pare Mountains, habitus (C) and face (D).

FIGURE 36. Stridulatory files of Melidia species A. M. laminata, Wajir District, Kenya B. M. laminata, Tanzania, Kilimanjaro; note differences in number of teeth between specimen from the Wajir District and Kilimanjaro C. M. brunneri Mashonaland, Salisbury (BMNH) D. M. adfinia n. sp.

FIGURE 37. Stridulatory area A. Melidia adfinia n. sp. and B. M. laminata.

FIGURE 38. Apices (A, C, E, G) and subgenital plates (B, D, F, H) of male Melidia species. A, B. M. claudiae C, D. M. brunneri E, F. M. laminata (Kilimanjaro) G, H. M. adfinia n. sp.

FIGURE 39. Subgenital plates of female Melidia species A. M. adfinia n. sp. B. M. kenyensis C. M. laminata (Damassa, Kenya) D. M. laminata (Kilimanjaro).

FIGURE 40. Subgenital plate of Melidia brunneri (BMNH, N Rhodesia, Luano Valley).