SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6e960b01ab8e7abd5ee01124da61af63999a7f52ecc61190bae7c0244418acb' 
  AND token = 'GwGtKe5HqNEjPsDIelVl77LKMriMGMOo7OYQr/ObNXg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00072

JSON explain

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