SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0e4e44f0926fa2a4be4ba47f1bea5c10e749312151d9106ed61ffacc0e2e47f5' 
  AND token = '+nmuQeFnXW5oT/IJbEtlwMEpnuEVe0w8MLnjF9FsETA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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