SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '87b551fee955befe231133a880801706dd869d7857f133269912aa45e114b992' 
  AND token = 'z0enhJ2r/hgJI2fPXEEZwpCRBlg6Qnl5O+7uhRiy7Ko=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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