SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47025efe14ae3c23058f9136d451dddcf04d0925113be04aa1a5179c1b65d967' 
  AND token = 'KYdZLw2uFzFpqk9nncG/0SeKQL/rktWhLGdFvjljHTo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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