SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99664b9e6f0e8a35f762f5b5762d36a530c69ab390044bb134744188c7143474' 
  AND token = 'zWR+3t7yDIU03Rzf4yWUecL33FiZzTS1fkCMRv7cbQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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