SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4561568c5ee123f14df616ee48cd869f9c42f4ccfe4f0a9cf1be26254420660a' 
  AND token = 'Kr5T5lYOQgW2yw0GDuVzeQDJdS1L13I0Qm65OjQd/Fo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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