SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'fda2a57c52d66773ba48407ab83f53165cfc57b1397166a56960a1e3081d7361' 
  AND token = 'BQuLZXFugNaIUYl5wnVeBZ+HPbEKZ6R4238h5csy5x0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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