SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dfecbbc9899736adb9b195840fda13f475ad4feab99a4faf6145bacbc1224c59' 
  AND token = '0XW9wio7gDEzvDMbUs2LDXFirSSVWOip8qJbCfYN2MU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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