SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a063a2b68454c292826cae006a1e814cac7b3e8900bc5f7e18b40e520edb484' 
  AND token = 'aoBKYc19Bu2TWVHlgHPolfwcWVTaNXt6qmnxK3EmipI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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