SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27d8411188a7129b19c7c5e4a023c067329e1347a33cb59a4cac30d0f522c676' 
  AND token = 'Q090JwXzoKorbCvwkXrqI8hdWKNHRLHqzdT26JQChdc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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