SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fabd668a7f39f9555eb5b94e890ad0be6b2f558d1df8bd8fcd9ad09b54f42431' 
  AND token = 'zqTaM7d1B/0fJQFdG3K+RV0u/+vMtAYpWXUYJYN5K+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00076

JSON explain

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