SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bff8f40dca94ad5d56a98af46db06d8cad526fcd214860b36c3c499fba343540' 
  AND token = '7s7aBEH30PNRwCbWL1GCcJfAxvMlDBSNvgTap38b1AM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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