SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2375470d29fed07ddf1924419eb628b6ce72f37b0fee27caf9e0ea2798394100' 
  AND token = 'IKpSyWRMyjQ7P0YDsCmC/HHlj8hV+NQk+62bdwrnH2o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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