SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '66e4858e7acab0093d2c2e3a46537b0e3bc439db02423df18d260d93bc809a27' 
  AND token = 'bFuyWFkcdWd4Q/A0gU1pySsXGiZ7yhKRMCJFfI6hJlQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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