SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b5411bf766baa41424fc6281f057cb86aa95baf1acf74a26b5f5cf53d127357' 
  AND token = 'SNdaz8Z0g7BpwmuMMlOMcpZncBV1u1QLwAXkbMdVh+4=' 
  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"
    }
  }
}