SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '520fc7fef7510ddf2c72366b115a847530ceb0ae8f7d00e756f92cb343717183' 
  AND token = 'oKVad9W9lX8BzHsLF3kiPnJ5/gYWYdLSqWgG9mTDvK8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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