SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '8a244426d757716549d6625ed4f4b53885022ba0c1b32517787c4eaf286dc6ef' 
  AND token = 'q6Hj1t8Pg6XXHej4L0EUB6HplBG9CE05vV8Wzdp73hA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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