Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'd7d1d5d3a5b796839cbbcdf35363d37a0c0670cd763a3568246c66b41782e2dd' 
  AND token = 'qMF+EaLdBS4ChSatUu3ytgGQg4gIqYZ3BES0Dhfb5jg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}