SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5594aad7b1662393ba81cdb5575e34116a98d9329e922c8883b3a68230f7f0bb' 
  AND token = 'ZHH/Id4PdBSMek5qJXcxRlRdpWbCUX/B9RY7wrzcqjU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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