SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea757dcf7b064a8c713057bccb684c1e02b45de3f838440ee74d688d094b0736' 
  AND token = 'sDgzVdjnAQgiW+G3kq97tIVXxrbVAzz3ajXX6Wil3T0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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