SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10a421c82c2b96b47e3fff2b422b6471522c83e51a3bc666c2bd79817c22c719' 
  AND token = 'rzeEQsw6tnuI+hZoLXAYBa4elwJgbEnrQhzQbR4YKVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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