SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2fd472251c1c4ba0bda32823baeffeb999ed505603bd1bf5833b50b9fd98dcf8' 
  AND token = 'WjJ2HER42uzXrt9Bdj9uwHyDWOXNMXC9LbTMiQg3liM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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