SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f07da3cbb14f2be65068c8044d4fe142061799d14acb6555e6535ce71d4cda06' 
  AND token = '9t/sERwo0+2yIO1PN1X5Y7xyEc1ZOKgv88O/HwqA5KI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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