SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ceb24627af22cc0092a268f07732a7cffdaa623d2411758a6ffe4730dab66244' 
  AND token = '5SIn/yqUq+6+g+hrI5qeUYbWxCIxOVC9bljPPdivwqk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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