Refer also to my Season Blog 2011 for comments on how the butterfly year is progressing.
Two fellow lepsters living nearby maintain similar lists - Guy Padfield (also in Switzerland) and Tim Cowles (Lyon).

Check list history - 2004, 2005, 2006, 2007, 2008, 2009, 2010

Season blogs 2005-2011 - I never complete my season blogs during the summer months so I've discontinued them.

1	Aglais urticae	Small Tortoiseshell	6th Feb	Valais	CH
2	Vanessa atalanta	Red Admiral	5th March	Vaud	CH
3	Nymphalis polychloros	Large Tortoiseshell	11th March	Vaud	CH
4	Pieris rapae	Small White	11th March	Vaud	CH
5	Gonepteryx rhamni	Brimstone	14th March	Vaud	CH
6	Leptidea sinapis	Wood White	14th March	Vaud	CH
7	Clossiana dia	Violet Fritillary	24th March	Vaud	CH
8	Pieris brassicae	Large White	24th March	Vaud	CH
9	Inachis io	Peacock	24th March	Vaud	CH
10	Pararge aegeria	Speckled Wood	25th March	Vaud	CH
11	Colias alfacariensis	Berger's Clouded Yellow	2nd April	Valais	CH
12	Carcharodus alceae	Mallow Skipper	2nd April	Valais	CH
13	Callophrys rubi	Green Hairstreak	2nd April	Valais	CH
14	Coenonympha pamphilus	Small Heath	2nd April	Valais	CH
15	Anthocharis cardamines	Orange Tip	2nd April	Valais	CH
16	Agrodiaetus thersites	Chapman's Blue	2nd April	Valais	CH
17	Celastrina argiolus	Holly Blue	2nd April	Valais	CH
18	Erynnis tages	Dingy Skipper	2nd April	Valais	CH
19	Issoria lathonia	Queen of Spain Fritillary	2nd April	Valais	CH
20	Nymphalis antiopa	Camberwell Beauty	2nd April	Valais	CH
21	Papilio machaon	Swallowtail	2nd April	Valais	CH
22	Pieris napi	Green Veined White	2nd April	Valais	CH
23	Polygonia c-album	Comma	2nd April	Valais	CH
24	Pontia edusa	Eastern Bath White	2nd April	Valais	CH
25	Pyrgus malvae	Grizzled Skipper	2nd April	Valais	CH
26	Iphiclides podalirius	Scarce Swallowtail	2nd April	Valais	CH
27	Glaucopsyche alexis	Green Underside Blue	9th April	Valais	CH
28	Melitaea cinxia	Glanville Fritillary	9th April	Valais	CH
29	Erebia triaria	de Prunner's Ringlet	9th April	Valais	CH
30	Colias croceus	Clouded Yellow	9th April	Valais	CH
31	Polyommatus icarus	Common Blue	9th April	Valais	CH
32	Scolitantides orion	Chequered Blue	9th April	Valais	CH
33	Lasiommata megera	Wall	9th April	Valais	CH
34	Cyclyrius webbianus	Canary Blue	16th April	Gran Canaria	ES
35	Pontia daplidice	Bath White	16th April	Gran Canaria	ES
36	Zizeeria knysna	African Grass Blue	16th April	Gran Canaria	ES
37	Danaus plexippus	Monarch	16th April	Gran Canaria	ES
38	Catopsilia florella	African Migrant	16th April	Gran Canaria	ES
39	Thymelicus christi (acteon)	Canary Skipper	16th April	Gran Canaria	ES
40	Lycaena phlaeas	Small Copper	16th April	Gran Canaria	ES
41	Hipparchia tamadabae (wyssii)	Gran Canaria Grayling	17th April	Gran Canaria	ES
42	Pararge xiphioides	Canary Speckled Wood	19th April	Gran Canaria	ES
43	Aricia agestis	Brown Argus	19th April	Gran Canaria	ES
44	Euchloe grancanariensis (belemia)	Gran Canaria Green Striped White	19th April	Gran Canaria	ES
45	Vanessa vulcania	Canary Red Admiral	19th April	Gran Canaria	ES
46	Cacyreus marshalli	Geranium Bronze	19th April	Gran Canaria	ES
47	Maniola jurtina	Meadow Brown	19th April	Gran Canaria	ES
48	Cynthia cardui	Painted Lady	22nd April	Gran Canaria	ES
49	Cyaniris semiargus	Mazarine Blue	1st May	Vaud	CH
50	Spialia sertorius	Red Underwing Skipper	1st May	Vaud	CH
51	Lysandra bellargus	Adonis Blue	1st May	Vaud	CH
52	Mellicta parthenoides	Meadow Fritillary	1st May	Vaud	CH
53	Lycaena tityrus	Sooty Copper	1st May	Vaud	CH
54	Erebia medusa	Woodland Ringlet	1st May	Vaud	CH
55	Artogeia mannii	Southern Small White	1st May	Vaud	CH
56	Colias hyale	Pale Clouded Yellow	1st May	Vaud	CH
57	Cupido minimus	Small Blue	1st May	Vaud	CH
58	Aporia crataegi	Black Veined White	7th May	Valais	CH
59	Melitaea didyma	Spotted Fritillary	7th May	Valais	CH
60	Plebicula dorylas	Turquoise Blue	7th May	Valais	CH
61	Aricia artaxerxes	Mountain Argus	7th May	Valais	CH
62	Boloria euphrosyne	Pearl Bordered Fritillary	7th May	Valais	CH
63	Mellicta aurelia	Nickerl's Fritillary	7th May	Valais	CH
64	Parnassius apollo	Apollo	7th May	Valais	CH
65	Melitaea diamina	False Heath Fritillary	7th May	Valais	CH
66	Pyrgus armoricanus	Obethur's Grizzled Skipper	7th May	Valais	CH
67	Pyrgus onopordi	Rosy Grizzled Skipper	7th May	Valais	CH
68	Eumedonia eumedon	Geranium Argus	7th May	Valais	CH
69	Pyrgus cartharmi	Safflower Skipper	7th May	Valais	CH
70	Cupido osiris	Osiris Blue	7th May	Valais	CH
71	Hamearis lucina	Duke of Burgundy Fritillary	7th May	Valais	CH
72	Pseudophilotes baton	Baton Blue	7th May	Valais	CH
73	Everes argiades	Short Tailed Blue	7th May	Valais	CH
74	Pyrgus serratulae	Olive Skipper	7th May	Valais	CH
75	Everes alcetas	Provencal Short Tailed Blue	7th May	Valais	CH
76	Araschnia levana	Map	8th May	Vaud	CH
77	Melitaea phoebe	Knapweed Fritillary	21st May	Geneva	CH
78	Mellicta athalia	Heath Fritillary	21st May	Geneva	CH
79	Brenthis Daphne	Marbled Fritillary	21st May	Geneva	CH
80	Melanargia galathea	Marbled White	21st May	Geneva	CH
81	Carterocephalus palaemon	Chequered Skipper	21st May	Geneva	CH
82	Coenonympha arcania	Pearly Heath	21st May	Geneva	CH
83	Plebejus argus	Silver Studded Blue	21st May	Geneva	CH
84	Plebejus argyrognomon	Reverdin's Blue	21st May	Geneva	CH
85	LImenitis populi	Poplar Admiral	21st May	Geneva	CH
86	Satyrium pruni	Black Hairstreak	21st May	Geneva	CH
87	Lycaena helle	Violet Copper	24th May	Vaud	CH
88	Paleochrysophanus hippothoe	Purple Edged Copper	24th May	Vaud	CH
89	Coenonympha hero	Scarce Heath	28th May	Ain	FR
90	Coenonympha glycerion	Chestnut Heath	28th May	Ain	FR
91	Thymelicus lineola	Essex Skipper	4th June	Vaud	CH
92	Argynnis adippe	High Brown Fritillary	4th June	Vaud	CH
93	Aphantopus hyperantus	Ringlet	4th June	Fribourg	CH
94	Maculinea nausithous	Dusky Large Blue	4th June	Fribourg	CH
95	Maculinea telejus	Scarce Large Blue	4th June	Fribourg	CH
96	Brenthis ino	Lesser Marbled Fritillary	4th June	Fribourg	CH
97	Ochlodes venata	Large Skipper	4th June	Fribourg	CH
98	Boloria selene	Small Pearl Bordered Fritillary	4th June	Fribourg	CH
99	Agrodiaetus damon	Damon Blue	12th June	Valais	CH
100	Agrodiaetus amanda	Amanda's Blue	12th June	Valais	CH
101	Carcharodus lavatherae	Marbled Skipper	12th June	Valais	CH
102	Lasiommata maera	Large Wall Brown	12th June	Valais	CH
103	Limenitis camilla	White Admiral	12th June	Valais	CH
104	Lycaena alciphron	Purple Shot Copper	12th June	Valais	CH
105	Lycaena virgaureae	Scarce Copper	12th June	Valais	CH
106	Maculinea arion	Large Blue	12th June	Valais	CH
107	Mellicta deione	Provencal Fritillary	12th June	Valais	CH
108	Plebejus idas	Idas Blue	12th June	Valais	CH
109	Satyrium ilicis	Ilex Hairstreak	12th June	Valais	CH
110	Satyrium spini	Blue Spot Hairstreak	12th June	Valais	CH
111	Satyrus ferula	Great Sooty Satyr	12th June	Valais	CH
112	Thymelicus sylvestris	Small Skipper	12th June	Valais	CH
113	Limenitis reducta	Southern White Admiral	12th June	Valais	CH
114	Albulina orbitulus	Alpine Argus	25th June	Piemont	IT
115	Argynnis aglaja	Dark Green Fritillary	25th June	Piemont	IT
116	Apatura iris	Purple Emperor	25th June	Piemont	IT
117	Clossiana titania	Titania's Fritillary	25th June	Piemont	IT
118	Clossiana thore	Thor's Fritillary	25th June	Piemont	IT
119	Argynnis niobe	Niobe Fritillary	25th June	Piemont	IT
120	Apatura ilia	Lesser Purple Emperor	25th June	Piemont	IT
121	Erebia oeme	Bright Eyed Ringlet	25th June	Piemont	IT
122	Erebia alberganus	Almond Eyed Ringlet	25th June	Piemont	IT
123	Lasiommata petropolitana	Northern Wall Brown	25th June	Piemont	IT
124	Heteropterus morpheus	Large Chequered Skipper	25th June	Piemont	IT
125	Neptis rivularis	Hungarian Glider	25th June	Piemont	IT
126	Erebia euryale	Large Ringlet	25th June	Piemont	IT
127	Lysandra coridon	Chalk Hill Blue	25th June	Valais	CH
128	Plebejus pylaon	Swiss Zephyr Blue	25th June	Valais	CH
129	Hipparchia semele	Grayling	25th June	Valais	CH
130	Hipparchia genava	Lesser Rock Grayling	25th June	Valais	CH
131	Euphydryas aurinia	Marsh Fritillary	26th June	Valais	CH
132	Euchloe simplonia	Mountain Dappled White	26th June	Valais	CH
133	Erebia mnestra	Mnestra's Ringlet	26th June	Valais	CH
134	Erebia meolans	Piedmont Ringlet	26th June	Valais	CH
135	Erebia melampus	Lesser Mountain Ringlet	26th June	Valais	CH
136	Coenonympha gardetta	Alpine Heath	26th June	Valais	CH
137	Pieris bryaoniae	Mountain Green Veined White	26th June	Valais	CH
138	Polyommatus eros	Eros Blue	28th June	Vaud	CH
139	Pyrgus alveus	Large Grizzled Skipper	28th June	Vaud	CH
140	Maculinea rebeli	Mountain Alcon Blue	28th June	Vaud	CH
141	Satyrium w-album	White Letter Hairstreak	28th June	Vaud	CH
142	Lopinga achine	Woodland Brown	28th June	Vaud	CH
143	Argynnis paphia	Silver Washed Fritillary	28th June	Vaud	CH
144	Agriades glandon	Glandon Blue	28th June	Vaud	CH
145	Boloria aquilonaris	Cranberry Fritillary	28th June	Vaud	CH
146	Erebia eriphyle	Eriphyle Ringlet	28th June	Vaud	CH
147	Erebia ligea	Arran Brown	28th June	Vaud	CH
148	Erebia manto	Yellow Spotted Ringlet	28th June	Vaud	CH
149	Kanetisa circe	Great Banded Grayling	28th June	Vaud	CH
150	Erebia tyndarus	Swiss Brassy Ringlet	2nd July	Valais	CH
151	Erebia epiphron	Mountain Ringlet	2nd July	Valais	CH
152	Erebia gorge	Silky Ringlet	2nd July	Valais	CH
153	Pontia callidice	Peak White	2nd July	Valais	CH
154	Boloria napaea	Mountain Fritillary	2nd July	Valais	CH
155	Parnassius phoebus	Small Apollo	2nd July	Valais	CH
156	Mellicta varia	Grison's Fritillary	2nd July	Valais	CH
157	Meleageria daphnis	Meleager's Blue	2nd July	Valais	CH
158	Hesperia comma	Silver Spotted Skipper	2nd July	Valais	CH
159	Boloria pales	Shepherd's Fritillary	2nd July	Valais	CH
160	Colias phicomone	Mountain Clouded Yellow	2nd July	Valais	CH
161	Hypodryas cynthia	Cynthia's Fritillary	2nd July	Valais	CH
162	Erebia pandrose	Dewy Ringlet	2nd July	Valais	CH
163	Pyrgus andromedae	Alpine Grizzled Skipper	2nd July	Valais	CH
164	Erebia pronoe	Water Ringlet	9th July	Valais	CH
165	Erebia aethiops	Scotch Argus	9th July	Valais	CH
166	Agrodiaetus escheri	Escher's Blue	11th July	Valais	CH
167	Coenonympha darwiniana	Darwin's Heath	11th July	Valais	CH
168	Erebia christi	Ratzer's Ringlet	11th July	Valais	CH
169	Erebia montana	Marbled Ringlet	11th July	Valais	CH
170	Hyponephele lycaon	Dusky Meadow Brown	11th July	Valais	CH
171	Erebia palarica	Chapman's Ringlet	16th July	Cantabrians	ES
172	Agriades pyrenaicus	Gavarnie Blue	16th July	Cantabrians	ES
173	Erebia cassioides	Common Brassy Ringlet	16th July	Cantabrians	ES
174	Melanargia russiae	Esper's Marbled White	17th July	Cantabrians	ES
175	Melanargia lachesis	Iberian Marbled White	17th July	Cantabrians	ES
176	Hipparchia alcyone	Rock Grayling	17th July	Cantabrians	ES
177	Muschampia proto	Sage Skipper	18th July	Burgos	ES
178	Pyronia bathseba	Spanish Gatekeeper	18th July	Burgos	ES
179	Pyronia cecilia	Southern Gatekeeper	18th July	Burgos	ES
180	Satyrium acaciae	Sloe Hairstreak	18th July	Burgos	ES
181	Agrodiaetus ripartii	Ripart's Anomalous Blue	18th July	Burgos	ES
182	Satyrium esculi	False Ilex Hairstreak	18th July	Burgos	ES
183	Agrodiaetus ainsae	Forster's Furry Blue	18th July	Burgos	ES
184	Thymelicus acteon	Lulworth Skipper	17th July	Burgos	ES
185	Pyronia tithonus	Gatekeeper	18th July	Burgos	ES
186	Lampides boeticus	Long Tailed Blue	18th July	Burgos	ES
187	Gonepteryx cleopatra	Cleopatra	18th July	Burgos	ES
188	Chazara briseis	Hermit	18th July	Burgos	ES
189	Coenonympha dorus	Dusky Heath	19th July	Soria	ES
190	Argynnis pandora	Cardinal	19th July	Soria	ES
191	Hipparchia fagi	Woodland Grayling	19th July	Soria	ES
192	Agrodiaetus fabressei	Obethur's Anomalous Blue	19th July	Soria	ES
193	Pyrgus cirsii	Cinquefoil Skipper	19th July	Soria	ES
194	Aricia morronensis	Spanish Argus	19th July	Soria	ES
195	Chazara prieuri	Southern Hermit	20th July	Montes Universales	ES
196	Satyrus actaea	Black Satyr	20th July	Montes Universales	ES
197	Leptotes pirithous	Lang's Short Tailed Blue	20th July	Montes Universales	ES
198	Pseudotergumia fidia	Striped Grayling	20th July	Montes Universales	ES
199	Lysandra albicans	Spanish Chalk Hill Blue	20th July	Montes Universales	ES
200	Brenthis hecate	Twin Spot Fritillary	22nd July	Montes Universales	ES
201	Laeosopis roboris	Spanish Purple Hairstreak	22nd July	Montes Universales	ES
202	Carcharodus boeticus	Southern Marbled Skipper	22nd July	Montes Universales	ES
203	Arethusana arethusa	False Grayling	22nd July	Montes Universales	ES
204	Plebicula nivescens	Mother of Pearl Blue	22nd July	Montes Universales	ES
205	Hyponephele lupina	Oriental Meadow Brown	22nd July	Montes Universales	ES
206	Quercusia quercus	Purple Hairstreak	24th July	Sierra de Guardarrama	ES
207	Lycaena bleusei	Blue Sooty Copper	24th July	Sierra de Guardarrama	ES
208	Neohipparchia statilinus	Tree Grayling	25th July	Madrid	ES
209	Pyrgus carlinae	Carline Skipper	31st July	Valais	CH
210	Minois dryas	Dryad	20th Aug	Valais	CH