SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '802f03540c4ec310e1cb8f062ca15857b831510e38bdb8d8d42f631d81cded72' 
  AND token = 'O+1hAqfO1jZ7MPAMJ42X44wwzeVkNpXWIQnpMQYeCdI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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