SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad02c2e9be059cf5db27c8d264e82716254dd345bf8af3783709525f754b671c' 
  AND token = 'ngA+9syC86/vUrdNEYivapOXV/NxW2f3IrYg4bMITto=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}