SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '86745c0003f1aa39f8f3186eea9d475226063988ec4058b486aed432f6257341' 
  AND token = 'a4gUqYWux7sSFjHlLDYto3glKhjEGiy9kRfWOtbZVgA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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