SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '76e05190f5c35b128859bbbfb43a240aa3fad0f5830964b789de42653e8b64c7' 
  AND token = '3C5et/p4wxUdIIUILBcxZYQfF93WHQ32UubvOLAcLPc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}