SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '568de233bb54a5c74b00d2decd707dc21bd9311ad425b2ded1b5a50f822aae4a' 
  AND token = 'CIA6t2PO3VJjdt5nDnkL/eaI5KDHS1G2r+ol9yXdvV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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