SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9d17c3c04b16f505766d1e9f489d750ae9245a52c794278ca695fda4a57a51d' 
  AND token = 'flkjiWx5TQkso1hYp3lH980wj+Wlz5AJawoJRk4Zgj8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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