SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b3406c86727b38c6cfc5833fae12721eb4c7d88fd132ed7892339a66da871cb' 
  AND token = '/ahXn/Q0Zml1m50/NURzRLBV2JjB/zT7FGyQCIbbjlI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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