Depressaria halophilella CHRÉTIEN, 1908

Buchner, Peter & Karsholt, Ole, 2019, Depressariinae of Madeira and the Azores Islands (Lepidoptera: Depressariidae), Beiträge Zur Entomologie = Contributions to Entomology 69 (2), pp. 331-353 : 343-346

Depressaria halophilella CHRÉTIEN, 1908

( Figs 28 –30, 33, 35)

Depressaria halophilella CHRÉTIEN, 1908a: 60 .

Depressaria ultimella sensu auct. (nec STAINTON). See remarks.

Examined material: Madeira. 1 , Funchal Lido , 17–22. iv.1974, leg. N. L. Wolff ( ZMUC) ; 5 , 3 , Porto Moniz, 0–10 m, 4–7.vii.1993, leg. O. Karsholt, genitalia slide Corley 2384, Karsholt 5039; 3 , same data but 13.x.1994; 1 , same data but 19–22.iv.1996 (all ZMUC) . Canary Islands: 1 , Gran Canaria, Baranco Virgen, Moya , 400 m, 20.vii.1984, leg. P. Olsen, B. Skule & P. S. Nielsen ( ZMUC) .

Description: Adult ( Figs 28 –30). Wingspan 15–18 mm, in fresh specimens ground colour of forewings a warm medium brown, veins covered by black scales, especially in distal part, black lines usually accompanied with some whitish scales. In older specimens ground colour turns to pale or translucent, while the black lines stay distinct, at least in part, which produce an increase of contrast in such specimens (Fig. 30).

Diagnosis: Closely related and similar to D. ultimella . Fresh specimens are usually distinguishable by a longitudinal concentration of white scales in the centre of the forewings ( Fig. 31A ) and a sharply angled transverse fascia at 3/4 (red underlined in Fig. 31B ), often also by a much darker ground colour.

BUCHNER, P. & KARSHOLT, O.: Depressariinae of Madeira and the Azores Islands

In the male genitalia of D. halophilella ( Fig. 33 ) A is an acute angle and B an obtuse angle; lateral outline of vinculum moderately to markedly convex (C), the number of cornuti (D) is usually eight or more (note, that cornuti can be lost and a small number may be an artefact). In D. ultimella (Fig. 34) A and B both about right angles; lateral outline of vinculum straight or slightly convex, cornuti usually 3–8.

In the female genitalia ( Fig. 35 ) D. halophilella differs from nearly all other Depressaria species by its very short apophyses anteriores (E). Only D. ultimella shows the same feature, and female genitalia of these two species are not separable.

Bionomics: Monophagous on Crithmum maritimum L.

( Apiaceae ), a strictly coastal plant.

Distribution: Widespread on coasts around the Mediterranean Sea, but not reaching the northern range of Crithmum maritimum (e.g. Great Britain). Larvae of D. ultimella feed on Oenanthe spec. , Apium spec. and Sium spec. (Apiaceae) .

Remarks: Whereas D. halophilella is a new name on the list of Lepidoptera found in Madeira the species has been known there for a long time, being misidentified under different names. We believe that halophilella was

already found in Madeira by Wollaston in the 1850s and recorded (as Siganorosis heracliana DEGEER ) by WALSINGHAM (1894: 546). Later WALSINGHAM (1908: 959–960) corrected his identification of the specimen to D. apiella (HÜBNER) (a junior synonym of D. daucella (DENIS & SCHIFFERMÜLLER)) . This was followed by REBEL (1917: 12; 1940: 8). CARVALHO (1995: 577) listed Depressaria rubricella (DENIS & SCHIFFERMÜLLER) (another synonym of D. daucella ) from Madeira without exact date and locality, probably based on the records by Walsingham and Rebel. The records of D. heracliana by REBEL (1901: 173) and D. pastinacella (DUPONCHEL) by ZHANG (1994: 178) most likely date back to Walsingham´s record of Wollaston´s specimen (see the note above under A. perezi for discussion of the synonymy of heracliana ). D. daucella is externally similar to halophilella , and since Walsingham changed his opinion about the single specimen it may not have been in perfect condition. We were unable to trace Wollaston´s specimen in the NHMUK, but we find it likely that it belonged to D. halophilella . The record of D. apiella (HÜBNER) from Tenerife by WALSINGHAM (1908: 959) refers to Depressaria sarahae GASTÓN & VIVES, 2017 ssp. tabelli BUCHNER, 2017 . AGUIAR & KARSHOLT (2006: 21, 47) listed D. halophilella from Madeira under the name of D. ultimella STAINTON because of misidentification.

Discussion: One of the aims of this paper is to provide the necessary information for correctly identifying Madeiran Depressariinae , because misidentifications have been common in the past.

Despite the low number of species of this subfamily found in Madeira: four in AGUIAR & KARSHOLT (2008: 340), six in Lvovsky (2004–2019) ( Ethmia bipunctella not included), these are unusually confused. The differences in the number between these two lists are due to the inclusion of two additional, misidentified species ( A. heracliana and A. daucella ) in the latter.

Many Depressariinae moths are difficult to identify, especially if only limited material in more or less worn condition is available. In former days the species of the subfamily were highly confused. If fresh specimens, preferably bred from larvae (and the host plant is noted) are available, many specimens can be identified from external characters. Moreover, the genitalia exhibit in most cases reliable characters for identification. And nowadays problematic specimens can be identified from their DNA-barcode. These tools were not available for lepidopterists in the 19 th and first part of the 20 th century, and it is therefore no wonder that the few specimens of Depressariinae available to them were often misidentified.

Both Madeira and the Azores Islands are well known for their many endemic animals and plants, and that is also the case for their Lepidoptera faunas. It is therefore rather surprising that none of these archipelagos house endemic species of Depressariinae – although two of the species

BUCHNER, P. & KARSHOLT, O.: Depressariinae of Madeira and the Azores Islands

listed above ( A. conciliatella and A. perezi ) are Macaronesian endemics, being only found in Madeira and in the Canary Islands.

Throughout the years the authors examined the collections of Microlepidoptera kept in most major natural history museums in Europe, and we were surprised that we found no or only very few specimens of Depressariinae from this area there. The short lists of examined material for each species listed above is thus not a result of superficiality, but reflects that these species are rare (or at least little collected) in Madeira and the Azores. It is therefore quite possible that these islands contain at least a few additional species which may turn up during future field work. For that we can especially recommend to search for larvae, especially on endemic plants of Apiaceae or Asteraceae .

Figures

Fig. 28: D. halophilella , Spain, Portbou, 29.ix.1974, e. l. Crithmum maritimum, leg. J. Klimesch, coll. ZSM. – Fig. 29: D. halophilella , France, Var, Port d´Alon, 31.iii.2014, e. l. Crithmum maritimum, leg. & coll. P. Sonderegger. – Fig. 30: D. halophilella , Spain, Mallorca, Albufera, 13.vi.2013, leg. D. Nilsson, coll. ZMUC.

Fig. 31: D. ultimella , Sweden, Öland, Långlött, Åstad, e. l. Conium, leg. R. Johansson, coll. ZMUC. – Fig. 32: D. ultimella , Belgium, Mons, e. l. Apium graveolens, leg. A. Dufrane, coll. ZSM.

Fig. 33: D. halophilella , France, Var, Port d´Alon, 31.iii.2014, e. l. Crithmum maritimum, leg. & coll. P. Sonderegger. –

Fig. 35: D. halophilella , France, Var, Port d´Alon, 12.iii.1995, e. l. Crithmum maritimum, leg. & cult. J. Nel (RCMC).