SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c158999a480af55953585fa84e638d7294badf359d8c1953144e5c0349d6db41' 
  AND token = 'Wr1eKhgU1qGu/9pydIbxBK5rdZ5AqLtWaKFG4G3e1Ww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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