SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7895bf844035dd4e44ba37b9a365713d5bd6fcb272f2f044f19888855494d5a' 
  AND token = 'LKZCBq8FQjHUjzwGS8vlxwFeuQm/tmpWLIkP/f+LNp8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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