SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9553471cb51a7ce0cc744ff13fb8b782c4c54e7f63679ab5c93bec2dd7d6cde8' 
  AND token = 'B2pxlPpwcU3uoDK+lfgkq9SXA9RUYMXiiuQbaigJbC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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