Macracantha hasselti (C. L. Koch, 1837) Macharoenboon & Siriwut & Jeratthitikul, 2021

Macharoenboon, Kongkit, Siriwut, Warut & Jeratthitikul, Ekgachai, 2021, A review of the taxonomy of spiny-backed orb-weaving spiders of the subfamily Gasteracanthinae (Araneae, Araneidae) in Thailand, ZooKeys 1032, pp. 17-62 : 17

Macracantha hasselti (C. L. Koch, 1837) comb. nov. Figures 9C-D , 12D-I

Gasteracantha hasseltii C. L. Koch, 1837: 29, fig. 267. Type locality: Indonesia, Java.

Gasteracantha hasseltii Full list of synonyms and usage of the name available in World Spider Catalog (2020).

Material.

Thailand • 3 ♀; Nakhon Ratchasima Province, Wang Nam Khiao District ; 14°32.57'N, 101°58.22'E; MUMNH-ARA-GAS013 • 2 ♀; Ratchaburi Province, Suan Phueng District , 13°34.88'N, 99°10.79'E; MUMNH-ARA-GAS014 • 2 ♀; Nan Province, Tha Wang Pha District ; 19°08.45'N, 100°45.38'E; MUMNH-ARA-GAS15 • 5 ♀; Ubon Ratchathani Province, Na Chaluai District, Wat Phupansoong ; 14°30.30'N, 105°16.33'E; MUMNH-ARA-GAS016 • 1 ♀; Nakhon Ratchasima Province, Pak Chong District ; 14°31.58'N, 101°22.13'E; MUMNH-ARA-GAS017 • 2 ♀; Saraburi Province, Kaeng Khoi District, Tha Maprang ; 14°29.85'N, 101°08.25'E; MUMNH-ARA-GAS018 • 4 ♀; Phrae Province, Rong Kwang District, Huai Rong Waterfall ; 18°26.51'N, 100°27.01'E; MUMNH-ARA-GAS019 • 5 ♀; Ubon Ratchathani Province, Det Udom District, Non Sombun ; 14°47.44'N, 105°06.16'E; MUMNH-ARA-GAS020 • 2 ♀; Nakhon Ratchasima Province, Pak Chong District, Phaya Yen ; 14°36.97'N, 101°15.90'E; MUMNH-ARA-GAS024 • 2 ♀; Phetchaburi Province, Kaeng Krachan District ; 12°53.41'N, 99°39.32'E; MUMNH-ARA-GAS025 • 1 ♀; Phetchaburi Province, Kaeng Krachan District ; 12°54.68'N, 99°38.45'E; MUMNH-ARA-GAS037 • 2 ♀; Chiang Mai Province, Mae Taeng District ; 19°08.51'N, 98°54.94'E; MUMNH-ARA-GAS038 • 4 ♀; Mae Hong Son Province, Mueang District, Pang Mu ; 19°18.12'N, 097°57.73'E; MUMNH-ARA-GAS049 • 5 ♀; Mae Hong Son Province, Mae La Noi District, Mae La Luang ; 18°32.31'N, 97°53.83'E; MUMNH-ARA-GAS050 • 3 ♀; Prachuap Khiri Khan Province, Bang Saphan District, Wat Tham Khao Wong ; 11°17.47'N, 99°29.72'E; MUMNH-ARA-GAS062 • 5 ♀; Chumphon Province, Tha Sae District, Pisadarn Cave ; 10°45.60'N, 99°13.77'E; MUMNH-ARA-GAS065 • 5 ♀; Sa Kaeo Province, Khlong Hat District, Saeng Tian Cave ; 13°18.93'N, 102°19.91'E; MUMNH-ARA-GAS070 • 5 ♀; Sa Kaeo Province, Khao Chakan District, Wat Tham Khao Chan ; 13°34.73'N, 102°05.56'E; MUMNH-ARA-GAS073 • 5 ♀; Kanchanaburi Province, Si Sawat District, Ong-ju Canal ; 14°48.45'N, 99°05.53'E; MUMNH-ARA-GAS083 • 4 ♀; Phetchabun Province, Lom Sak District ; 16°43.74'N, 101°20.22'E; MUMNH-ARA-GAS088 • 3 ♀; Chaiyaphum Province, Phakdi Chumphon District, Wua Daeng Cave ; 16°04.55'N, 101°26.46'E; MUMNH-ARA-GAS097 • 3 ♀; Chiang Mai Province, Mae Rim District, Mae Raem ; 18°55.10'N, 98°54.51'E; MUMNH-ARA-GAS100 • 3 ♀; Kanchanaburi Province, Thong Pha Phum District, Huai Kayeng ; 14°37.85'N, 98°34.32'E; MUMNH-ARA-GAS109 • 1 ♀; Kanchanaburi Province, Sai Yok District, Tha Sao ; 14°21.14'N, 98°57.28'E; MUMNH-ARA-GAS113 • 1 ♀; Kanchanaburi Province, Si Sawat District, Khao Chot ; 14°48.26'N, 99°10.93'E; MUMNH-ARA-GAS121 • 3 ♀; Kanchanaburi Province, Si Sawat District, Tha Kradan ; 14°22.41'N, 99°09.02'E; MUMNH-ARA-GAS125 .

Diagnosis.

Sternum black with yellow patches near anterior edge, coxae II and III, and the apex. Abdomen octagonal. Anterior edge of abdomen curved between anterior spines. Dorsal side of abdomen yellow with black and white patches near anterior margin. Anterior and posterior spines small, and sharp at the tips. Median spines longest, tapering toward the tip. Ventral side of abdomen black with scattered yellow stripes. Spinnerets placed on strongly elevated black sclerotized structure. Ten anterior edge sigilla subequal in size. Four median sigilla arranged in a trapezoid. Ten posterior edge sigilla arranged in a straight line, with the first pair and the second and third sigilla from the middle close together. Outer posterior edge with nine sigilla in total: five sigilla placed near posterior spines, two sigilla on each side. Epigynum subtriangular with sock-shaped structures, opposite to each other (Fig. 12D, G ). Scape very long, tongue-shaped, pointed posteriorly (Fig. 12E, H ). Spermathecae balloon-shaped (Fig. 12D, G ). Copulatory ducts bulging distally, encapsulated by sclerotized structure (Fig. 12D, G ). Fertilization ducts emerging posteriorly from spermathecae (Fig. 12D, G ).

Variation.

The patch near abdominal anterior margin is narrow or absent in some specimens. Two morphs are found in this study: a sharp spines morph (Figs 9C ; 12D-F ) with its morphology as in the diagnosis, and a long spines morph (figs 9D; 12G-I), which is characterized by the six abdominal spines being longer than in the sharp spines morph. The median spines are longest, straight without tapering, and with spikes at the bases. The epigynum of the two morphs are similar in shape.

Remarks.

Macracantha hasselti was once classified in genus Gasteracantha ( World Spider Catalog 2020). However, the phylogenetic tree in this study recovered a sister relationship between M. arcuata and M. hasselti , which is supported by their synapomorphic characters (see discussion) in both external and internal morphologies. Based on this evidence, we propose to reclassify these two species in the same genus.

The long spines morph resembles Gasteracantha dalyi Pocock, 1900, especially as their female genital structures are identical ( Tikader 1982). They are differentiated from each other by the morphology of abdominal spines. Anterior and posterior spines of M. hasselti are longer and the median spines are shorter than in G. dalyi ( Tikader 1982).

Distribution and habitat.

India, China, Cambodia, Vietnam, Myanmar, Thailand, Malaysia, Singapore, and Indonesia (Java, and Sumatra) ( Yin et al. 2012; Sen et al. 2015; World Spider Catalog 2020). Macracantha hasselti builds a vertical web under the shade of large trees or thick shrubs.

Figures

Figure 9. Females of A, B Macracantha arcuata and C, D M. hasselti showing dorsal view (left) and ventral view (right) A orange morph, specimen from Prachuap Khiri Khan (MUMNH-ARA-MAC 008) B white morph, specimen from Kanchanaburi (MUMNH-ARA-MAC 013 - W 1) C sharp spines morph, specimen from Saraburi (MUMNH-ARA-GAS 018) D long spines morph, specimen from Phetchaburi (MUMNH-ARA-GAS 025).

Figure 12. Female genitalia of A-C Macracantha arcuata D-I M. hasselti J-L Thelacantha brevispina. Genitalia are shown in dorsal view (A, D, G, J), ventral view from external (B, E, H, K), and posterior view (C, F, I, L).