SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8f77a0add5b8fe560cdecff049ddabb166cbf3de83939a1798ae30f99bb90b42' 
  AND token = 'u85GnP5ZcPU8Ib5yUAJldHAjO7EDp4Yeg7P/FAGIfzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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