SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84e3e464d6b28a82c81c3abd7ce2b99485186fa753e67c0b5e0fc761dcd96e24' 
  AND token = 'Ii3StfYJCaBR+Ma4rRgGDOJqzGC0gqBJEY2UxVi0w28=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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