SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eccf1409805811593df1438674c2e9d81e6d27bc23d163abfbede9525244060a' 
  AND token = 'wQmzbvkZQuVXU1yHdN0t+F7QOgKjXDJrjW84UzHlmzY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}