SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '87a9591043374a876daa09423c068c99dfca1c8ca84d8ce0bec44b6e4fc04612' 
  AND token = '+gtSYwXoEo4AGwT0Mi46EdQyHgsLrbpuz1Po+O4iOj4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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