SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '796b2fd16b1aa815c65c425d64fa176af48f9c2f96bf2bf71110404e2277f8a1' 
  AND token = 'vv0NlF4PkgIOf9Ymu1Y9ao8ZpUuolbRU2CVWlYQDBkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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