Ephemera (Sinephemera) cornea, Lei & Zhou, 2024

Lei, Zhi-Ming & Zhou, Chang-Fa, 2024, The subgenus Sinephemera Kluge, 2004 in China (Ephemeroptera: Ephemeridae: Ephemera Linnaeus, 1758), Zootaxa 5517 (1), pp. 1-68 : 17-22

publication ID	https://doi.org/ 10.11646/zootaxa.5517.1.1
publication LSID	lsid:zoobank.org:pub:B73493AB-2F80-43B2-9396-218EC54A0472
persistent identifier	https://treatment.plazi.org/id/C513C56F-0509-C102-FF11-FD47F7CEF816
treatment provided by	Plazi
scientific name	Ephemera (Sinephemera) cornea
status	sp. nov.

Treatment

Ephemera (Sinephemera) cornea sp. nov. ( Figs 13–18 View FIGURE 13 View FIGURE 14 View FIGURE 15 View FIGURE 16 View FIGURE 17 View FIGURE 18 , 64 View FIGURE 64 )

Description

Mature nymph: Body length 23.0–25.0 mm, caudal filament 7.0–9.0 mm. Two mandibular tusks subequal in length, longer than head in dorsal view ( Figs 13 View FIGURE 13 , 14A View FIGURE 14 ). Area among ocelli black ( Figs 13 View FIGURE 13 , 14A View FIGURE 14 ). Projected frons slightly convergent anteriorly, slightly longer than wide, anterior margin concaved into 1/3 length ( Figs 13 View FIGURE 13 , 14A View FIGURE 14 ). Mouthparts shown in Figs 14C–J View FIGURE 14 , apex of maxillary palpi blunt ( Fig. 14J View FIGURE 14 ). Pronotum with one pair of dorsal stripes, anterior and posterior margins black to purple ( Fig. 13A View FIGURE 13 ). Legs similar to other species ( Figs 15A–C View FIGURE 15 ). Tergites I–II with a median spine, that of tergite II usually larger than first one, but both of them sometimes indistinct ( Fig. 14B View FIGURE 14 ). Gills I–V at posterolateral angles of tergites, gills VI–VII at middle; gills similar to other species ( Figs 15D–E View FIGURE 15 ). Color pattern of tergites: segments I–X with three pairs of deep brown straight stripes, but some stripes in segments I–V sometimes indistinct, especially those of females. Two median pairs of stripes convergent anteriorly but lateral wider pair convergent posteriorly; stripes on tergites VII–IX slightly straighter than others ( Figs 13A, C View FIGURE 13 ). Sternites I–IX with pair of oblique stripes, those of segments I–V sometimes not visible, those of segments VIII–IX nearly straight; stripes on sternite I usually meet at middle point of anterior margin but others separated ( Figs 13B, D View FIGURE 13 ).

Male imagine:Body length 19.2–19.7 mm, caudal filaments 33.8–34.3 mm, forewings 17.7–18.3 mm, hindwings 6.6–7.0 mm. Body deep brown to black purple, median portion of pronotum and mesonotum slightly lighter than others ( Fig. 16A View FIGURE 16 ). Forelegs black, mid- and hindlegs light brown, tibiae lighter ( Figs 16A–C View FIGURE 16 , 17A–C View FIGURE 17 ). Length ratio of forefemora: tibia: tarsus=1.0: 1.8: 1.4, ratio of foretarsus segments=1.0: 3.3: 2.5: 1.7: 1.1 ( Fig. 17A View FIGURE 17 ). Length ratio of middle femora: tibia: tarsus=1.0: 1.2: 0.6 and tarsal segments=1.0: 1.0: 0.9: 1.6 ( Fig. 17B View FIGURE 17 ), Length ratio of hind femora: tibia: tarsus =1.0: 1.1: 0.5 and tarsal segments=1.0: 1.2: 1.0: 2.1 ( Fig. 17C View FIGURE 17 ). Membranes of both forewings and hindwings tinged with amber to light brown; all crossveins of wings tinged with brown to purple pigments ( Figs 16C View FIGURE 16 , 17D–F View FIGURE 17 ), forewings with clear median band, MP 2 and CuA fused at base ( Figs 17D–E View FIGURE 17 ), veinlets of A 1 less than ten ( Fig. 17E View FIGURE 17 ); hindwings with one to two dots in middle, outer margin of hindwings slightly tinged ( Fig. 17F View FIGURE 17 ). Abdomen: Tergite II with a median spine ( Fig. 17G View FIGURE 17 ). Tergites I–X with three pairs of oblique stripes, lateral pair wider than others and convergent posteriorly; two median pairs convergent anteriorly ( Fig. 16A View FIGURE 16 ). Sternites I–X with a pair of oblique stripes, those of sternites VIII–X nearly straight; in most cases, segment X black, with indistinct color marking ( Fig. 16B View FIGURE 16 ); lateral and posterior margins of all tergites and sternites pale ( Fig. 16C View FIGURE 16 ).

Genitalia: Deep brown ( Figs 17H–K View FIGURE 17 ). Styliger plate extended posteriorly, forming square lobe, its posterior margin with median V-shaped notch ( Figs 17I View FIGURE 17 ). Combined length of forceps segments III–IV subequal to segment I and ca. half of segment II ( Fig. 17I View FIGURE 17 ). Except base, two penes divergent widely; lateral half of penes sclerotized but mesal half membranous ( Figs 17H–I View FIGURE 17 ); each penis with a subapical spur ventrally ( Figs 17J–K View FIGURE 17 ).

Female imagine: Body length 21.0– 22.5 mm, caudal filaments 20.0–21.0 mm, forewing 21.5–22.5 mm, hindwing 7.0–8.0 mm. Color pattern similar to male but much paler, in most cases, markings and stripes of body distinct but not merged together ( Figs 16D–F View FIGURE 16 ). Length ratio of forefemur: tibia: tarsus = 1.0: 1.2: 0.9, ratio of foretarsus segments = 1.0: 2.1: 2.2: 1.3: 1.3 ( Fig. 18A View FIGURE 18 ). Those two ratios of midleg = 1.0: 1.3: 0.6 and 1.0: 0.9: 0.9: 1.5 ( Fig. 18B View FIGURE 18 ), hindleg = 1.0: 1.0: 0.4 and 1.0: 1.2: 0.9: 1.7 ( Fig. 18C View FIGURE 18 ). Wings with grey to indistinct dots ( Figs 18D–E View FIGURE 18 ). Tergites I–VI with two pairs of stripes, fused together into a somewhat triangular marking ( Fig. 16D View FIGURE 16 ); tergites VII–X with three pairs of stripes, inner pair narrower than other two pairs, lateral two pairs fused together too ( Fig. 16D View FIGURE 16 ). Sternites I–X with pair of oblique stripes ( Figs 16E–F View FIGURE 16 ). Tergites I and II each with median spine, second one usually larger than first one ( Fig. 18F View FIGURE 18 ).

Male subimagine: Body length 15.0 mm, caudal filaments 15.0 mm. Head and thorax paler than abdomen, similar to male imagine.

Female subimagine: Body length 18.0–19.0 mm, caudal filament 12.0 mm. Similar to female imagine.

Etymology: The specific name is derived from the Latin word ‘cornea’ (feminine, nominative case), meaning ‘horn-like,’ indicating the penial shape.

Diagnosis: (1) In nymph, this species can be identified by long mandibular tusks and frons ( Figs 13 View FIGURE 13 , 14A View FIGURE 14 ). (2) Its tergites I–X have three pairs of stripes although some of them can fuse together ( Fig. 13 View FIGURE 13 ). (3) The distinct spines on tergites II or I–II are helpful to its identification ( Figs 14B View FIGURE 14 ).

The male imagines can be identified by: (1) tinged wings, hindwings with dots ( Figs 17D–F View FIGURE 17 ); (2) abdominal stripe pattern on tergites I–X (three pairs, Fig. 16A View FIGURE 16 ); (3) notched styliger plate ( Fig. 17I View FIGURE 17 ); (4) shapes of forceps and penes (segments III–IV of forceps relatively short, penes strong, horn-like, Figs 17H–K View FIGURE 17 ); (5) spine on tergite II ( Fig. 17G View FIGURE 17 ). Females: (1) spines on tergites I–II ( Fig. 18F View FIGURE 18 ), (2) stripes on tergites I–X (especially three pairs in tergites VII–X, the lateral pair is oblique, Figs 16D–F View FIGURE 16 ).

Comparison: Generally, this species is similar to E. strigata and E. obliqua sp. nov. in terms of abdominal stripes, but those two species never have three pairs of stripes on tergites I–V but one oblique pair. The penes of them are totally different, those of Ephemera cornea sp. nov. are much longer than E. strigata and E. obliqua sp. nov. ( Figs 17H–K View FIGURE 17 , 25F View FIGURE 25 , 62E View FIGURE 62 ) The hindwings of E. strigata and E. obliqua sp. nov. have no dots but Ephemera cornea sp. nov. has ( Figs 17F View FIGURE 17 , 25E View FIGURE 25 , 62B View FIGURE 62 ).

In nymph, besides abdominal stripes, the mandibular tusks and frons of this species are longer than those of E. strigata and E. obliqua sp. nov.

Material: China: Holotype: ♂ imagine, near gate of Pudacuo scene (27.800407°N, 99.907370°E), Shangri- La, Yunnan province, China, leg. Zheng-Xin Ma, 2021 -IV-18–23; paratypes: 10 ♂ and 10 ♀ imagines, 2 ♂ and 2 ♀ subimagines 2 nymphs, same as the holotype: others: 5 nymphs, near gate of Shi-Meng-Xia scene (23.992841°N, 101.537676°E), Xing-Ping county, Yunnan province, leg. Xu-Hong-Yi Zheng, 2022-II-9; 5 nymphs, Wu-Long street, Bai-Lu town (31.158951°N, 103.865165°E), Pengzhou county , Sichuan province, leg. Peng-Xu Mu , 2022- II-9 . GoogleMaps

Distribution ( Fig. 64 View FIGURE 64 ): China (Yunnan, Sichuan).