SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1490e9edc93affa389098f673461561008749ac6486ac829a707ecbe5a2e4fca' 
  AND token = '4APebm3nRiX08B48QwGtKv0Xr75QcVVpFK5JbDAeIdM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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