SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ea38f887b543402264857d1da27ba4bcc1e51eab581ce4b12f996d04ea541085' 
  AND token = 'n+0rljAdRH+/+/B92ls5JJKAVZHdDyrYMLovPoSGxos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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