SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f769fdbb8f4754d6932cd6e2172840ba41ccdad933c56fad5a8cfd94064f490' 
  AND token = 'yt335jgxwNnqHRcQhbU1vRSEgvTZqGJPiNSw01HYfrE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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