SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c309965da2ad920ebd899e53a8a5fa37eda410da1cbcbd4f316bfa38fa8614b' 
  AND token = 'Kr/eMbsbOVZqKL4BSlx1C0elbBU/BfKtl4lCBL84thU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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