SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f0a1b069d4cb7cf690ad9bffb372e28155af25376a5b6bec81904e7ed99d744' 
  AND token = '7XSXMBPF/KbVWG9nlpbmQ8voNRXvYL/f/XBGBBX6sTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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