SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44544279d18cb41fb3cae728954ec30a31755fb74faab6641d253f0348401e65' 
  AND token = 'uhEdo4oCqZfPhSSquok9iUrX6pp0Xkc8vXF4BXY+V/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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