SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eaaa6b190cb369b272753eb7f2bf358aecda5c929d5ea66e17600f3b26c8c2cc' 
  AND token = '8/YMdGuQoVpdcqB6IwiWDV0MmX4MErbQ/M6LCifIkZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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