SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b40530b666e0cb9fb5b9a8077c0f238f44ecce9fdc6b914502ebd3157c53f614' 
  AND token = 'Wj5XCgeHJc7/FXJLHL+ERkqVk8/UICN4aP3IwrZT/SQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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