SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c3e026906d6f7de54fcdc8b77f48baef3aa12b0ea234983dc80330ca13362e8' 
  AND token = 'iQxKVZm4Ya1n/NiCVHdLvsYz2ZPAOr42LWZ1wh5Qg0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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