SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9cbda1e9efd23af45d2e383881b028d0405853d4241ee79de349c056dcb90db8' 
  AND token = 'Bb+MXdARCCVa5xAPgwhT4Up7HvFCyj1eZVg39Y8Zl1k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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