SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46efcadfab6853fdff8e739b6a4aba60de93c467e2720b4ce2f985a1f5ed8458' 
  AND token = 'svzzeACJVIK5YY7I2RqxJdLry1UT0QMfWMyAUQGKqg0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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