SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc661ad15cf1a0a6e6c827e59f78722a8974ac443efad117b06790dd53d58156' 
  AND token = 'Xjlh7Mvbw794HxqUOQU44QVZy4oI4prgMVV2HNCX+gk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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