SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'cbd93b36fd913c44426c63060d14b12e618506c09df368dd458fb1f8c0df9275' 
  AND token = 'Dq5TWo9xhHUrEtlIJ6cP+Lbr+YgO2LJOvehIYC+o7iU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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