SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ee5b99be041dda81906a9a68c3d247a0ff13245bf628b7fe553210a4f899fc9' 
  AND token = 'VgYJxqCxmOJno58nSFmDQvKcASFNsY5VruXvzjsyN1M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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