SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f578bf4c6ec1cf33e5f4aad522bd64543bb5d66e5feca7c7cecd74880595323' 
  AND token = 'Wim6q5IyqoMg03wuERAyQaNVjTSWdkcM3DeeOLCSyCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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