Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0c14fa6f0e82d15b2a087ce2f8bb02a26c25f3df7b48b12363e6f032290c0bb' 
  AND token = 'UNfDZnB3yynSWM37K2gFpb2e/ZwV4KgBpo/uT4D6HCA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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