SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccff72ebf5af7e2c07173e6423b7c61b3425c1c2dcfa6704c16dcad0025f3d8c' 
  AND token = 'L2dmWUYGmWmN8BOV+juFLSqXwG3wKvkbsZ76GZ7gHTM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00151

JSON explain

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