SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc05e5719e167967db91799ebae509e63b0d393dd684dc60de34aec714d6a5a5' 
  AND token = 'nItfGO+qLPB7m94kqDc5AiqhidVxVyoOBgC+eN6hN3s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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