SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a8a65cb515191c255098d236adac174a9003eb809ebd88edb376e4c8ac1d0601' 
  AND token = 'fHfafEJey8OeMeomsHQD/ZiVrdqPy2MmW8oNEb9iFcc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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