SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbfb711d8413be9b6b812a620ee8dbe79ff5b4fdbd706ae6ace6f241330f2430' 
  AND token = 'so4QgpAkJV6o+5w5+owejoHp+UNZwqDxKbqlVZI0jRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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