SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70a333b9e54dc2a12ef99d6e87a4053211e1d783e4b259ee7a99c52310a08c4d' 
  AND token = 'apjcbJqKltOuRDCijwaAI82/mY540mabBemxu5e5Pik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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