SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b46e569a18400621ceb90df3939540a845766afad17d5209363d83e5284300d8' 
  AND token = 'hV/rcivdCdcUislLVFwd6xBWh11OvAc01X1e4gPTfVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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