Stephanothrips Trybom, 1913

Mound, Laurence A., Lima, Élison Fabrício B. & O’Donnell, Cheryle A., 2023, What is a genus-interpreting structural diversity among species of urothripine Phlaeothripinae (Thysanoptera), Zootaxa 5319 (1), pp. 91-102 : 99

Stephanothrips Trybom

Stephanothrips Trybom, 1912: 42 . Type species Stephanothrips buffai Trybom.

Baenothrips Crawford, 1948: 39 . Type species Baenothrips guatemalensis Crawford , syn.n.

Verrucothrips Stannard, 1952: 128. Type species Amphibolothrips (Verrucothrips) caenosa Stannard.

Ramachandraiella Ananthakrishnan, 1964: 228 . Type species Ramachandraiella minuta Ananthakrishnan.

Transithrips Bournier, 1963: 81 . Type species Transithrips asper Bournier.

Bournieria Ananthakrishnan, 1966: 2 . Type species Bournieria indica Ananthakrishnan.

Four of the generic synonyms indicated above were discussed by Mound (1972: 92), but the validity of Baenothrips has not been questioned since Stannard (1952). The sole distinction between Baenothrips and Stephanothrips has been in the degree of separation between antennal segments III–V, being separate in the first genus but largely fused in the second. Baenothrips guatemalensis , the type species of that genus, is interpreted as having segments III–V distinct from each other ( Fig. 5 ), although the separation between them is by no means clear. Among the various species placed in Baenothrips only asper and cuneatus have these segments clearly separate ( Fig. 8 ). In the only known specimen of guatemalensis segments VII and VIII are fused with scarcely any trace of suture, and this is also true of chiliensis ( Fig. 7 ). Very similar to these in structure and sculpture, the Australian species, moundi , has segment VIII clearly distinct ( Fig. 6 ). A further problem is that in another Australian species, B. caenosus , antennal segments VII and VIII can be either fused or separate ( Mound 1972). There is also a lack of clarity in distinctions between some described species. For example, Bhatti (2002) published a detailed morphological study of a paratype of asper , recognizing that specimens identified as asper from India do not represent that African species. The original illustration of asper by Bournier, as well as the illustrations of a paratype by Bhatti, indicate that, in this species from Angola, antennal segments III–V are clearly distinct from each other, much as in cuneatus ( Fig. 8 ). In contrast, the antennae of Indian specimens labelled by Ananthakrishnan as asper (Ooty, vii.1970) have segments III–V broadly joined.

Our interpretation is that antennal segment fusion has been subject to several reversals among the various species, and that this character state cannot be employed to distinguish natural groups. As a result, the genus Baenothrips is here considered a synonym of Stephanothrips , and that genus will now include 47 species. These comprise 26 species from the Asian tropics, nine from Australia, three from Africa, and four from southern USA, plus four from South America where they are possibly introduced (see above Geographic considerations). In addition, because the only known males of occidentalis were taken in Thailand ( Okajima & Urushihara 1995b), it is probable that this pantropical species is also Asian in origin. Since several of the nine species from Australia are known only from the northern subtropical parts of this continent, it is clear that the distribution of species in this genus is primarily in association with the southeast Asian tropics. The new synonymy of Baenothrips with Stephanothrips results in the 15 new combinations listed in Table 1.

Figures

FIGURES 1–20. Antennae of urothripines. (1) Amphibolothrips grassii; (2) A. knechteli; (3) Conocephalothrips tricolor; (4) Bebelothrips flavicinctus; (5) Baenothrips guatemalensis; (6) B. moundi; (7) B. chiliensis; (8) B. cuneatus; (9) Bradythrips hesperus; (10) Stephanothrips buffai; (11) S. uvarovi (paratype); (12) S. uvarovi (Brazil); (13) S. howei; (14) S. barretti; (15) S, broomei; (16–17) S. erythrinus (paratypes); (18) S. austrinus; (19) S. adnatus; (20) Antennae of five Asian Stephanothrips species in Okajima (1989).