Parameristomerinx, Woodley, Norman E., 2010

Woodley, Norman E., 2010, Parameristomerinx copelandi — a new genus and species of Afrotropical Pachygastrinae and a new generic synonym of Dolichodema Kertész (Diptera: Stratiomyidae), Zootaxa 2397, pp. 41-47 : 42-43

Parameristomerinx gen. n.

Type species, Parameristomerinx copelandi sp. n., by present designation.

Diagnosis. The combination of the elongate antennal flagellum with the apical flagellomere short and bluntly, conically tapered; the unarmed scutellum; and the abdomen longer than wide will separate Parameristomerinx from all other Afrotropical Pachygastrinae . I regard the structure of the apex of the antennal flagellum as autapomorphic for the genus.

In Lindner’s (1966) key to Afrotropical genera of Pachygastrinae , Parameristomerinx keys to Chelonomima Enderlein (paragraph 12); however Chelonomima has the antenna longer than the head, and the flagellum is composed of eight similar flagellomeres that do not taper noticeably toward the apex. Also, these flies are typically conspicuously marked with yellow coloration, sometimes being almost entirely yellow. If you make the alternative choice at paragraph 13, that the antennae are not moniliform, then you end up at paragraph 22 from which it is difficult to continue. This section of Lindner’s key contains genera that are included in the above key.

Within the group of genera related to Meristomerinx the shortened antennal flagellum found in Parameristomerinx is similar to that found in Meristomeringina , although it is relatively shorter. Also, in Meristomeringina the eighth flagellomere is longer than the seventh ( Woodley 1987: figs. 7–8). Meristomeringina is easily separated from Parameristomerinx because it has a pair of scutellar spines.

Description. Male. Head moderately large, about as wide as thorax ( Fig. 1 ). Upper frons reduced to tiny triangle below the moderately prominent ocellar tubercle; lower frons with margins diverging toward face; face with margins evenly, widely diverging toward oral margin, face rounded and receding in profile ( Fig. 3 ). Gena visible in lateral view, evenly rounded, contiguous with wider postgena, which in profile evenly merges with postocciput and becomes invisible toward vertex. Eye large, contiguous on upper frons ( Fig. 1 ), upper ommatidia slightly larger than lower ones, without distinct demarcation of change in size, virtually bare, with only, very short, sparsely scattered setae only visible at high magnification. Antenna ( Fig. 5 ) shorter than length of head, scape and pedicel subequal in length, the latter slightly expanded apically; flagellum elongate conical, basal flagellomere about 1.5 times length of second, second through seventh about equal in length; first two flagellomeres about equal in diameter, subsequent flagellomeres gradually decreasing in diameter; eighth flagellomere minute, about half diameter of and slightly shorter than seventh, with small, hair-like seta at apex. Palpus two-segmented, segments subequal in length, second slightly expanded at rounded apex.

Thorax with scutum convex; scutellum trapezoidal with rounded apex, subapical region with slight depression giving scutellum slightly margined appearance, without spines; subscutellum with tomentum on dorsal half. Legs unremarkable, without significant modifications. Wing evenly set with dense microtrichia; R2+3 originating distal to apex of discal cell; R4 present; alula of usual form, rounded apically, completely set with microtrichia.

Abdomen 1.2 times longer than wide, slightly wider than thorax, tergites flat, more or less in same plane.

Female. Differs from male as follows: Head with eyes smaller than in male, dichoptic ( Fig. 2 ), upper frons parallel-sided, 0.36 width of head, slightly, evenly convex but slightly depressed just anterior and lateral of anterior ocellus. Postgena and occiput visible in lateral view. Eye with ommatidia small, uniform in size

Abdomen with two-segmented cerci, segments about equal in length, second elongate-ovoid.

Etymology. Parameristomerinx is a modification of the name of the related genus Meristomerinx , to which a Greek prefix has been added. Meristomerinx is considered here to be a Greek noun, third declension. The grammatical gender of the latter genus-group name is not obvious from the original description or its subsequent usage. Greek nouns with comparable consonant-ending stems are either masculine or feminine, often depending on how the word was used historically. The gender of Meristomerinx and Parameristomerinx is determined here to be feminine.

Figures

FIGURES 1 – 4. Habitus images of Parameristomerinx copelandi gen. n., sp. n. 1, holotype male, dorsal view. 2, allotype female, dorsal view. 3, holotype male, left lateral view. 4, allotype female, left lateral view.

FIGURES 5 – 9. Antennae and male terminalia of Parameristomerinx copelandi. 5, male antenna, lateral view. 6, female antenna, lateral view. 7, male phallic complex, dorsal view. 8, male epandrium and postgenital segments, dorsal view. 9, genital capsule, dorsal view.