SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b826461501c8d85bf75b3b2bd35ffb857ab2101db47d13f4895ea274d68b232e' 
  AND token = 'Fd3vOBfKNDhj9oXfm20Mg9osDFzoSQQ7GVb8EfGv2/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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