SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '693df4db3b6df78fb041944888a948213bcaa70d58057f12f972b375e707fb4e' 
  AND token = 'wbQ7inp/vylVKS6TBLqjGI/iusfMYCXDuUm04GyjDoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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