SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'bf543fa1c45d1b13a53c3b2177c04059f526f68e9b697af86fd29d8dab3af10a' 
  AND token = 'UebBjJDaRiDHRVhXNSeEnJUMKT7+vMFfUBA/s30o1gs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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