SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ed373f3ed6475ea611a70cd335066c37226bea4b6fc8aea7b1829fe54bc704e' 
  AND token = 'gkbEBgfrGur+sqt0iWKGNuH4+Kz+KBlAOa3fsRuz8c4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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