SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a1d9c96a00d0cb8a8d73dac045d5cf163657be7188b5ce4bb95d5dea386dae8' 
  AND token = '6gdCF/Ebyy6BQUsHU0FGtLNBq1Lt/YgEwGUNci+yxoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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