SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5bdc6c391066f3fbb93cb933d84b86b41ed341a1aa7eaa9f0b70d774a161a8ec' 
  AND token = 'S2Vvf9ZdBePCdauRdajU/xEKme+ySJM/geYdGKqO75A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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