SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3868fc5fb49fcdcc906ae2b659b56efc2e3ba2275c6c24007c7443dd6c0b4905' 
  AND token = '13VjoM+V+GHN8xKjU0Urg5tsoyLx0C/hXwZQTOIVOs4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00067

JSON explain

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