SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '805af7c3bc6d9bde5116c3dea9c4f55f1dfdf72f01c175230a041113fac7cc28' 
  AND token = 'eg8IaYwsVo5NUZYCu0B/uVsqFN3Sjaog+OVY0NWmBV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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