SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '65f1fa5d62475ea580c39661f3d179f8ca29fd26e7a371ccc1bb622d7cb5a56d' 
  AND token = 'rMCgZfi0VCpiBCh/5bJLw7vA1YezDwf8If+QFfeJHGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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