SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7be415e28c5f816493814fa260deba7ebab6084328f38c819b821a8f5e5a59c8' 
  AND token = 'Eo9dEi0d+u3Zyjiz/ys9lYhOpK3fBlJwJj/CA4gS8wA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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