SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce35d8beaa63311d4ac60208b4caba57766d2578f531141188b1dd133db8a0a0' 
  AND token = 'HqrjkLdQ2HAddST1aG9dTRuyS/axH1JrofoHQxMhP9s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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