SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e08094ed3e97bc1d7d8276e7af58fe99f72e2a30e8207366036e71517c0df15b' 
  AND token = 'gauO7wLIzZJMIoH881+rgYkbERFSbY1zKDyza7GmQr0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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