SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a92b975f8e096cea377cb4133467a2a8b41e56fcbafa0388fe2b5c0e72d05485' 
  AND token = 'V2qA3XT+/nq/sUzIYX7PuvKEemesGrJjM7YFzNrY2Pg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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