SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e66faeca754366bc15ce98c5960d434fb9c3a3fa13c4b96b7cfb741baa22adbb' 
  AND token = 'X8wpoYtRKxECcLZYke+VMC+mCI6WBjdYorVJrFJOmKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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