Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a185a8a7aac87819f67bc2cec624950dd30fbd21f77e7d0f256986d4a69a93a2' 
  AND token = 'oy3Qu8Wn/bLqw7y2b9mo0bBuYUmezuQ5H+mHs4PqR4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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