SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57327a9770dcbfc06b1f6a22b2020ffce511d4f45ec9fdb679797af69388e62f' 
  AND token = 'ANeptFWRNBS9wyI+8Ja07z1KTOXBAH/CxEpv1M8zvxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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