SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97854a8d8fa69745176dad9abf9adfc2ad9586a62453bf172c1ca4cfe6479ede' 
  AND token = 'Hoib5LGHXCPu4hJ/wZxlOhln6vvmJt6IIkF9n9qhk6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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