SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90625f07551dd8a093929515d58b70f19752c410fdca1bbb126cef1ac6eaf438' 
  AND token = 'e5MIvDL1ywd+a6mDY1lJSNj6aK6tzYazgyOUkbI0KyU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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