SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd382056a4953d21843f00a500a14ab8ad6f1f15f1d797710032cb7395503733b' 
  AND token = 'Fq9QsxFr9MYXS8eFD4u1teXkUxuEVNUsnFuB0PAikJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}