SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2bc3ab2416b64480e6bf89ed7413496af0c6ebfbdd6fed0899e7125d6a8bbd6' 
  AND token = 'N4EdLOzWXGu9eYoxCes0y71/5xlzJm+sEg20ZLGcSPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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