SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ef5b2704cc388773280a559d839c72dec2d9d8e11ad80ede59c34cb7f848bba' 
  AND token = 'jNPLn5wfOVv6gcJB7ZBqTsQ+/4PfLHbRBxW/v9nLnAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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