SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6991174bb7c4a029887a5b3123e42be46095d0745293be7d06c0cbf2ef9d0d17' 
  AND token = 'wIJaLXmmY7elKvzrNu5hoh0RtLYQt2K7TMnOejKbWdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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