Samsoniella aranea T. Wang, Ming J. Chen & B. Huang, 2024

Wang, Ting, Li, Jun, Chang, Xiaoyun, Li, Zengzhi, Hywel-Jones, Nigel L., Huang, Bo & Chen, Mingjun, 2024, Morphology and multigene phylogeny reveal three new species of Samsoniella (Cordycipitaceae, Hypocreales) from spiders in China, MycoKeys 101, pp. 329-346 : 329

Samsoniella aranea T. Wang, Ming J. Chen & B. Huang sp. nov.

Fig. 3

Etymology.

Referring to its host, spider, family Araneae .

Typification.

China. Anhui Province: Xuancheng City, the Jingting Mountains National Forest Park, on spiders, in the litter layer, 15 March 2006 and 27 April 2006, Mingjun Chen & Xueqiu Zhao, holotype XC20060427-06, ex-holotype XC20060315-12. Sequences from strains RCEF2868, RCEF2831 and RCEF 2870 have been submitted to GenBank with accession numbers: RCEF2868: SSU = OM268846; LSU = OM268851; TEF = OM483867; RPB1 = OM751883; RPB2 = OM802501. RCEF2831: SSU = OM268845; LSU = OM268850; TEF = OM483866; RPB1 = OM751882; RPB2 = OM802500. RCEF 2870: SSU = OR978314; LSU = O978317; TEF = OR966517; RPB1 = OR989965; RPB2 = OR989966.

Description.

Sexual morph: Undetermined. Asexual morph: Isaria -like. Mycellium on the spider consisting of white, smooth, branched, septate, 1.6-2.5 μm diam hyphae (Fig. 3A ). Conidiophores solitary, arising from superficial hyphae, smooth, cylindrical, flexuous. Phialides verticillate, in whorl of 2-4, 5.0-12.6 × 1.2-2.3 μm, with basal portion swollen to ellipsoidal, tapering into a distinct neck, 4.0-6.0 × 0.8-1.0μm. Conidia in chains, fusiform, aseptate, hyaline, 2.1-3.6 × 1.5-2.4 μm.

Culture characteristics.

Colonies on 1/4 SDAY, attaining a diam of 34.5-41.0 mm in 14 d at 25 °C, floccose, colonies white to cream-yellowish, with white smooth and neat edge (Fig. 3B ), reverse light yellowish, sporulating abundantly. Hyphae smooth-walled, branched, hyaline, septate, 1.5-2.3 μm wide. Conidiophores smooth-walled, cylindrical, verticillate, 4.8-16.0 × 1.4-2.0 μm. Phialides in whorls of two to four, usually solitary on hyphae, basal portion cylindrical, tapering to a distinct neck; 5.1-16.9 μm long, 1.3-2.1 μm wide at the base, and 0.5-1.0 μm wide at the apex (Fig. 3D ). Conidia in chains, smooth-walled, hyaline, elliptical, occasionally fusiform, 1.9-3.5 × 1.4-2.6 μm (Fig. 3G ). Chlamydospores and synnemata not observed.

Colonies on PDA, attaining a diam of 34.5-36 mm in 14 d at 25 °C, floccose, colonies white to cream-yellowish, with a white smooth and neat edge, forming radial folds from the center outwards (Fig. 3C ). Reverse yolk yellowish, sporulating abundantly. Hyphae smooth walled, branched, hyaline, septate, 1.5-2.6 μm wide. Conidiophores smooth - walled, cylindrical, verticillate. Phialides in whorls of two to four, usually solitary on hyphae, basal portion cylindrical, tapering to a distinct neck; 6.9-11.2 μm long, 1.4-1.9 μm wide at the base, and 0.5-0.9μm wide at the apex (Fig. 3E ). Conidia 1-celled, in chains, smooth-walled, hyaline, elliptical, occasionally fusiform, 1.9-3.4 × 1.2-2.4 μm (Fig. 3F ).

Habitat.

Occurring on spiders in the litter layer.

Notes.

Samsoniella aranea was readily classified within the genus Samsoniella through phylogenetic analyses (Fig. 1 ). Analysis of the combined multigene dataset unveiled that S. aranea forms an independent branch and shares a close relationship with S. yunnanensis . However, notable distinctions were observed between the two species. Unlike S. yunnanensis , where synnemata arise from insect cocoons, synnemata of S. aranea were not observed. Additionally, distinct growth characteristics were noted, with colonies of S. yunnanensis exhibiting a faster growth rate on PDA compared to S. aranea . Morphological differences were evident in the colonies on PDA, with S. aranea colonies being floccose, white to cream-yellowish, and having a yolk-yellowish reverse. On the other hand, colonies of S. yunnanensis were described as loose and hairy, appearing white with a reddish-brown reverse.

Figures

Figure 1. Phylogenetic relationships between the genus Samsoniella and closely-related species, based on multigene dataset (SSU, LSU, TEF, RPB 1 and RPB 2) for maximum likelihood / Bayesian method. Note: The ML tree presented here, and the node support rate of the two methods is displayed on the branches. The maximum likelihood support values / Bayesian posterior probabilities value (≥ 75 % / 0.75) are shown, and bold lines mean support for the two analyses were 98 %. The typical strain of the species is marked with the superscript " T "

Figure 3. Samsoniella aranea A fungus on spider B colony on SDAY / 4 C colony on PDA D, G conidiophores structure and conidia on SDAY / 4 E, F conidiophores structure and conidia on PDA. Scale bars: 15 mm (B, C); 10 μm (D-G).