SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffe824315cf3dd23d316cc13e16553b124a7b35b24b18a2a22e0672268d1bf0e' 
  AND token = 'Ob9ElR/SrEJaUeYQ5IbInJMlxnMXeqsHWHkaq+L6M6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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