SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1267bc081e3847b61368d83fd4e63868fe72abe6f7b3c66542e11cb3cace847a' 
  AND token = 'iUwWVTQpYyQGn6ssBzMOqkrQIsAv75HCuBXQzF0VZ/k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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