SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab1038a90c1ff375b02d9756df5af250cb00a090551a3f1d09416d7fa73f4a11' 
  AND token = 'Nz5TZcj/dch6E5WigscnJk0jBI2603t/FtEjPIP2oPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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