SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'db99bb1114a2020340e39cd3dc6e90dc67c205254bfb1c6aebbe2c415d17f88d' 
  AND token = '//pHkpxKoPkADNVdutjsjw6pSBATHTXhFOgmwyVRXMc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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