SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe7d26f975d022eef613f5fe36b4b86a1c8a3b1426903246f9712aaa325c56e4' 
  AND token = 'tQf0O4WydmRoXKWxkbJbx12b3gyEd1t7TdtuPOmNpvs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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