SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab97891e5623f3dbded6ceb1561c0a03943a9af19664ed752b3288f0e7a6e8d3' 
  AND token = 'fKao4MOJSkUmu+WVmX3oav0WNPny/wO9CCffrZo4CBQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00125

JSON explain

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