Baeus rachanae Veenakumari

Kamalanathan, Veenakumari, Mohanraj, Prashanth, Samuel, D. K. & Reddy, M. Krishna, 2020, Revision of Indian species of Baeus Haliday (Hymenoptera: Platygastroidea: Scelionidae), Journal of Natural History 54 (13 - 14), pp. 813-917: 881-883

publication ID 10.1080/00222933.2020.1770885

publication LSID

persistent identifier

treatment provided by


scientific name

Baeus rachanae Veenakumari

sp. n.

Baeus rachanae Veenakumari   , sp. n. ( Figure 25 View Figure 25 (a–d))

Holotype. Female; body length = 0.69 (0.65–0.74) mm; n = 3

Colour ( Figure 25 View Figure 25 (a)). Head, mesonotum and metasoma honey brown, propodeum paler than remainder; hyperoccipital carina black; a black band present on posterior margins of mesoscutum and mesoscutellum; A1, A2 dark brown, clava paler than A2, remaining antennomeres yellowish brown; legs yellowish brown to dark brown.

Head ( Figure 25 View Figure 25 (a–d)). Head 1.05 (0.98–1.11)× as wide as high; IOS 0.53 (0.51–0.54)× width of head, 1.27 (1.23–1.31)× eye length; eye (L: W = 12.0:8.4) setose, not touching hyperoccipital carina posteriorly; head height 2.32 (2.32–2.42) × eye length; POL>LOL in ratio of 21.3:10.0; lateral ocellus contiguous with orbits; pilosity of moderate density, setae of medium length subequal to those on mesonotum and metasoma; distance between posterior margin of lateral ocellus from hyperoccipital carina 0.73 (0.71–0.75)× MOD; interantennal process triangular, pointed, weakly rugose; central keel not distinct; facial striae extending up to 0.50 (0.45–0.52)× the distance from mandibular end to lower orbit; single malar stria present; frons smooth; upper frons and vertex smooth; gena dorsally weakly reticulate, remainder smooth, with sparse short foveae on postero-ventral margin, 4.20 (4.12–4.31)× as long as wide; anterior margin of gena in contact with 0.40 (0.39–- 0.42)× length of ventral margin of eye; length of A1and clava subequal; length of A2 0.43 (0.41–0.45)× that of A1.

Mesosoma ( Figure 25 View Figure 25 (a,c)). Mesoscutum and mesoscutellum 0.44 (0.41–0.51)× and 0.18 (0.16–0.19)× as long as wide, respectively; mesoscutum imbricate, mesoscutellum smooth; metascutellum not visible; propodeum dorsally smooth, 0.70 (0.65–0.76)× the length of mesoscutellum; pilosity of moderate density, setae of medium length; anterolateral margin of mesoscutellum with a weak fovea; lateral pronotal area dorsally imbricate, remainder smooth except for sparse weak vertical striations antero-medially; ventral margin of lateral pronotal area extending as a blunt projection; transverse carinae on dorsal mesopleuron terminate above the level of dorsal metapleuron; mesopleuron ventrally with weak vertical striae followed by a coriaceous reticulate patch and semicircular carinae, remainder smooth; mesopleuron extending as a short narrow projection ventrally; mesopleural pit elongate; metapleuron smooth; posterior metapleural suture straight except for a basal curve and not bending towards mesopleuron dorsally; dorsal level of posterior metapleural suture ventral to level of antero-lateral margin of T 2; anteroventral margin of metapleuron extending as a blunt projection; sculpturing of propodeum posterior to spiracle with 2 short carinae followed by two long transverse carinae, each carina with a seta, region posterior to spiracle smooth; a crescent shaped carina present ventral to propodeal spiracle enclosing three long setae; remainder of lateral propodeum smooth with sparse transverse carinae ventrally; propodeal spiracular opening tear-drop shaped.

Metasoma ( Figure 25 View Figure 25 (a,c)). Metasoma 1.15 (1.03–1.28)× as long as wide; pilosity of moderate density, setae of medium length; T 2 anteriorly weakly imbricate, posteriorly smooth; remaining tergites smooth.

Host. Reared from unidentified spider eggs

Material examined. Holotype: Female ( ICAR / NBAIR / P3263), INDIA: Assam: Jorhat, Assam Agriculture University ( AAU), 26 ° 43 ʹ 26 ʹ ’ N 94 ° 11 ʹ 53 ʹ ’E, 101 m, reared from spider eggs, 12. VI.2009   ; Paratypes: 6 females ( ICAR / NBAIR /P3264–P3269), same data as holotype.

Etymology. This species is named after my friend and lab mate R. R. Rachana, with whom I shared many an interesting discussion. The name is treated as a noun in the genitive case.

Diagnosis. This species is closer to B. tripurasundari   sp. n. but differs from it in the following character states. In B. rachanae   sp. n. medial frons is smooth, sculpture beneath propodeal spiracle with an evenly curved crescent shaped carina, mesopleural pit elongate and posterior metapleural suture almost straight; whereas in B. tripurasundari   sp. n. medial frons with semicircular striae, sculpture beneath propodeal spiracle with an oblique carina enclosing a short carina medially, mesopleural pit short and posterior metapleural suture curving towards mesopleuron dorsally. This species is also closer to B. tumburu   sp. n. and the diagnosis is mentioned under the latter.


Institute of Oceanographic Sciences


University of Modena and Reggio Emilia, Department of Biology


Tavera, Department of Geology and Geophysics


Addis Ababa University, Department of Biology