SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f9795e052afb3ce8efd8b2e861a5b82eee53bd050752691a4fc78a91a63cbfd0' 
  AND token = '5PGT4lraa/kz5UdJX/TvEGn4zZ7w1cIAnzSDH8QuD6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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