SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb1aaf4d372ca497d0faec161ae91d6714e9b323eff52cd8a04f6b954585c00f' 
  AND token = 'F+eVp/cmsMflXYXTGwsqisMqTmVdyw9Ww1lkaxk1j+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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