SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f025f4554b035d2f9cb9e9ecfc651bf7bf4da334e49f31616e47627368193160' 
  AND token = 'ETRBtC19jyHGfuviRQu4VUKDw6aBc/XahXcu8Z4gcFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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