SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62df21cb0b6fcfeccf12256dd8c1e298122cd585d29361d33f4e532c7cdac3aa' 
  AND token = 'cTWYb0SzOVlBUijJywZ9zJUSHnO0r1cYmTuukSkkqYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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