SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0153fc3f8c67755acaaf91ea70c06359c397781e6a17943a00de2fc0fbf4b13' 
  AND token = 'uRkOmgljUeTGwZxLvIJim2NBmEFMzZc3pMT9Aa2EBkQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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