SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '58df73898f91f9b91b8bb9c716565351c0687cb4e3127b279ee71d327f316659' 
  AND token = 'xS3Fcpo3irqqO4Yunzoo/6tw8szQ09X12LGJEJ0mUSk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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