SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bd617997551032c4531bd3731aea3ae23364de1c405841fb553a9a8bcd6cefe' 
  AND token = 'AYmGSdcgX1jDnfPYqVnzUSQZnzKkZ6PKJA49jPZd8z0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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