SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1acae522ec8ff3495725b25d5fb6430f02ff2763c073788837a5756b22ee58a3' 
  AND token = 'AgJ6nnNsoGQ4m2Vk/G5SHhsgqZItrUDFucLPF4vxv5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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