SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4377b12c37b5c4db9cf7f14c9eeaca1e8e6d1f1a53f40898c81f1af5ea9610c0' 
  AND token = '5W0aAprNuKJqKjKwso3qlp7vBZY2UeZ3ULFTKV/BJ6g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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