SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3508e84fa94574dd7f4fcac1bc574167cfb6a2ad151b107a507413e6b1603a8b' 
  AND token = 'YyqL47CPZI9uw93dNGflD/EkfSMjp2mzwU3QRZQRyx0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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