SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9326a657d92ddecc9d94621357fcb6fae402ca2cb502118ce2c2878f5e5074b3' 
  AND token = 'KLip2Icg00V1cP6SsjjBsCoZiPwXVoxXdfrkS0idPS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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