SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9a8cb183f7560f65d7a726661ae6e21a44fb25e69577fe43e3d6ec83d1090458' 
  AND token = '+2xFJtuPRRNLx++ohuvFTH9FWIKBD1hTcmwAr1ZpkrQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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