SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a6d1fb6e4bde2683d687a10c3da78c8f425b48e7f761c94bfe40539b7931fa5d' 
  AND token = 'je0XJHC/lHLBDvghKJagIV9B3DWpP7+YBQ4ZYeU4A8s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}