SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4051562a6c555dedf426ad6cf3d60f052e89f021c0aabc8567f16e2594c5658' 
  AND token = 'yWPXXmmXjWmhpht7VzSJIhBifk2KF94YaHl8h9Q1Joo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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