SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c07563e7ede978721e1b000072c063cdf24d26af7a8d16f9570b36792d26e3ab' 
  AND token = '3m7ss8bMT+ukX+9qyuwWnsnUu/HD8odOYXbn4NLO0eQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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