SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4688edafcae61e06ed826a3a83e3168b59e385e03732f597e2613ea10eaf24cd' 
  AND token = 'aRyCzNeA2r2MMA3Qru6Wl1+4jYCs9naY5EhH7A+le4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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