SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2945b26e746edc76d710fac5a47859cdc25f6709d8868c758688cc2db29878a5' 
  AND token = 'FNx/5MSVdUKbOYJUU1gkVzxl/h7RW0gg/hLIJwG1TcA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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