SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e97273cca955c1e325acc3eaef70b81dfeae4b267d803af6084a3dc996e96b49' 
  AND token = 'WnVFzQjtPW0JVNX2+i0m2s/XZ/wxOgSCpI41tZMH8Tw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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