SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57a98044529a0ad734b0a1f1f7250a03c339cdb7049146138f73d95ec6617f84' 
  AND token = 'CIyTaQPJNXhP4fRwfj/y/eGuLf/ZKY6O89nJGGyQasY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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