SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd661848398d52190366b76b674ed06bdfdf1131c5c98e0f623446e37fa894b56' 
  AND token = 'dAryDD5hxjFlDNLRGDcyfngviMJarL8XxseOO+HZZJI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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