SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0329f8e460c8783e4126df04feb20d16137fc545159f65ef355335303828bfec' 
  AND token = 'PizPvf8GeE+xQua30XqH+KL+8o3hbLTkNmW4dVo+Igc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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