Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '308ffbf1e6e95606b6faf68082a7d1f226808186e048f683924730a5d78c0959' 
  AND token = '2UQ6ZgMHOYDOc+R94x3mHNKyleG+L+ILHaxdvhV0HDs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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