SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31d1fd408d217c08f2bbe339a9cd6f18447cbac4369e59ac627f7e98252be507' 
  AND token = 'FCyALg3QKluoGd3W89V1A8OG2i10w4DUj3wUvrCKjkw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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