SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d7194066990872359ac9c0cc121f94f69b6262cf84949393d1c14bcbcf2c2fc' 
  AND token = 'p8gbXpMAvvjJRY4csphxUqszvaKWiua5Zr/JP/zP+VE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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