SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc380673d7d5e7e330ba125cca0fd7942f9f553696197ac57dc51f2ee290ea8b' 
  AND token = 'QnLmFay9jI0sogN07kgXQI1Guu7IO9ydITD5FC85Bp8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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