SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1e5cbc443f9974cb3d6a74a58fba3653dea17df8f5cfd0e69d85b3ba89e99edc' 
  AND token = 'OaWCe/dHO42FwTRV9aAzLw4OU9IMywcZGKTMVX8x6Ss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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