SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d8081711cc3bba29d9d5bfff866786116dd2f97a2963715ebbb771274a0e515' 
  AND token = 'V5+zHM1jFvIylvJ9e13uoxvX0gFo74swz+afhMwoR5Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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