SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f3cfee773e4a287e6525340643ce05f5f987bd0c2195ece4e409c5a5b2e87859' 
  AND token = 'zcWa3KjL6wozFclO9RfxHewZEdGuHS9EeOz975VqHwg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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