Potamanthus luteus (Linnaeus, 1767)

Li, Wen-Juan & Zhou, Chang-Fa, 2022, A detailed comparison of two species in the genus Potamanthus Pictet, 1843 from China (Ephemeroptera, Potamanthidae), ZooKeys 1125, pp. 193-205 : 193

Potamanthus luteus (Linnaeus, 1767)

Ephemera luteus Linnaeus, 1767: 906. Type: England.

Ephemera reticulata Fourcroy, 1785: 351. Synonymized by Eaton (1871: 76).

Baetis mellea Curtis, 1834: 121. Types: subimago. Synonymized by Eaton (1871: 76).

Baetis marginalis Burmeister, 1839: 801. Types: male and female. Synonymized by Eaton (1871: 76).

Ephemera flavicans Rambur, 1842: 296. Types: male and female, from Paris, France. Synonymized by Eaton (1871: 76).

Ephemera chlorotica Rambur, 1842: 296. Types: male and female subimagoes, from Paris, France. Synonymized by Walker (1853: 539).

Potamanthus luteus (Linnaeus): Pictet 1843: 205; Eaton 1884: 79.

Potamanthus ferreri Pictet, 1843: 203. Types: male, from Italy. Synonymized by Bae and McCafferty (1991: 51).

Eucharidis reaumurii Joly & Joly, 1876: 314. Types: nymph. Synonymized by Eaton (1884: 79).

Potamanthus na Imanishi, 1940: 180, fig. 2 (nymph). Synonymized by Bae and McCafferty (1991: 54).

Potamanthus naa Imanishi, 1940: 181 (nymph). Synonymized by Bae and McCafferty (1991: 54).

Potamanthus luteus : Wu 1987a: 336 (female, first record from China); You and Gui 1995: 115, fig. 122 (male); Bauernfeind and Soldán 2012: 634 (adult, nymph, egg).

Potamanthus (Patamanthus) luteus oriens : Bae and McCafferty 1991: 54, fig. 4, 125 (subspecies established); Bae 1997: 408; Zhou 2013: 202; Zhou et al. 2015: 252.

Potamanthus luteus oriens : Quan et al. 2002: 257.

Distribution.

China (Heilongjiang and Jilin Province); Palearctic and Oriental. From England east through Europe and Asia Minor, south to North Africa.

Description.

see Bae and McCafferty (1991) or Bauernfeind and Soldán (2012).

Diagnosis.

see diagnosis of P. huoshanensis . Males of this species can be identified by the more distinct color of the wings and penial lobes (Figs 5E-H , 6 ) and the foretibiae longer than the tarsi (Fig. 4A, C ). The nymphs can be distinguished by the slightly larger mandibular tusks, longer foretibiae (Figs 2I, L , 3E-H ) and apical segment of the maxillary palpi (Fig. 3K, L ).

Remarks.

Bae and McCafferty (1991) mentioned that the nymphs of the subspecies Potamanthus luteus oriens have very pointed anterolateral projections of the pronotal and vestigial spine-row on the forefemora. In our material, the former character is distinct, and the transverse spine-row was not recognizable, which is consistent with the description of European P. luteus provided by Bauernfeind and Soldán (2012). However, we do not know whether this variation is just at the population level or representative of different subspecies or geographical populations, because we have no material from abroad for comparison.

In the present comparison and photos, we can see clearly that P. huoshanensis and P. luteus oriens are extremely similar in both nymphal and imaginal structures. The differences between them are very slight. Therefore, it is not surprising that Bae and McCafferty (1991) recognized Japanese materials of P. huoshanensis as P. luteus oriens , which was later corrected by Ishiwata (2001).

The distribution of P. luteus is wide, from Africa to Japan. In contrast, P. huoshanensis was reported from three allopatric sites in Japan and China. Biogeographic and genetic studies at the population level are required for these species.

At the generic level, the definitions of the genera Potamanthus and Potamanthodes were updated by Li and Zhou (2022) and confirmed by the characters presented in this study.

Figures

Figure 2. Male and female head, thorax, foreleg claw, foreleg, midleg and hindleg of nymph of two Potamanthus species: A-D, I-K P. huoshanensis and E-H, L-N P. luteus.

Figure 3. Labrum, hypopharynx, left mandible, right mandible, maxilla and labium of nymph mouthparts of two Potamanthus species: A, C, E, G, I, K, M P. huoshanensis and B, D, F, H, J, L, N P. luteus. dd: distal dentisetae; dp: proximal dentisetae.

Figure 4. Male and female adult morphology of two Potamanthus species: A, B P. huoshanensis and C, D P. luteus.

Figure 5. Male head, female head, forewing and hindwing of two Potamanthus species: A, B, E, F P. huoshanensis and C, D, G, H P. luteus.

Figure 6. Genitalia (ventral and dorsal view) and penis (ventral, dorsal and lateral view) of two Potamanthus species: A-E P. huoshanensis and F-J P. luteus.