SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f5a42e383bd1b00dc2db43ff1bc7dc9fccf1455506446f4d727e7c20f0b61a7' 
  AND token = 'LpIzZPeo5x0tkrjLT8qU1+QvmlPm4JA+UxTxqKM1zO8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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