SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4007a30d962f844be90fc282a5255c9936f6fab419803264be9f3ad78fa004a6' 
  AND token = 'ttnC3UOXSGoK67tempMBJx6DwjZeSI457EreFBKtCQ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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