SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a379e4288e142940b10a539d48a7cfd4746af675ffb52246c8256424528046f' 
  AND token = 'F3doWYZgbuF31Vy6Z/vGxJPNnMr5qUj7mLZwdQEk5Ik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00126

JSON explain

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