SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7e33c75d6b0d3fd5f197a7d65ef2998ef22a47fd1ddc234d9950ce899a6eb26' 
  AND token = 'dQURdAUXEGH1ZW0ZeL/sRpJYA4V1gjlWBAPZDNImlqA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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