SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1c71e61423829c2620ecf589b4334a9f9e8ce05b92854c66e28ed8ac9da8e4d2' 
  AND token = 'P1/Uu2gp4V5yaBlBHh+LrGkoCPOOVdbn/vDQ7jxdpwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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