SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dcb35d34aa101283f34f5349c84cf90f8e197e8811d58fa696162bd95b1d0be2' 
  AND token = 'RRzfUdDm9PIAt+/tomC/9eZ/w4nBSVOOLqTjPD37Kk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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