SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2b0cdc7a1e36f743cb35c4c3f1d23e0807baeda9fa36389e85295dcac9ceba1' 
  AND token = 'EcmVolGUsp4gxpjbKBZS/vm8gdFwmxJruUTP4CBrfSo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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