SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a1885880632ab14fa3713c074550015c2194ed94248d982a2e77ddd5c8ad8aa' 
  AND token = 'MfYhR0jhcZ0gv5BLcxwKg4Qr9b39psKTk7aJPXs9Krs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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