Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4bd29a77e34efac581d3565fea164b6c9afc54f8a21da904a6aa8a93a3e20fd' 
  AND token = 'UlOASFXY9IRnD9vpqT+RBPJ3MdRo8QvhQ1PJeCTeR9Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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