SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b01703449ce5c1bc97be8d1eedd3c6c4357ae9040eb5cbec7ea508cc89e2ce89' 
  AND token = 'Ae6EkY51pKTn76wKlr9q1TN1A+KwT1yQpX8SiAFtk8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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