SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '620cec586e5dc1cd4e3fab3f77acd7a49bf9008c57c49ae22dc963475a6d08b6' 
  AND token = 'gygC/+lCI5Gv5/J1WGU/ZECfo5Se+ltlPxXvJ91Tfhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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