SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7d2b01b85cc42af37c80af261258c9b9b4183fd8d8b16fb79e61184a7dc0998' 
  AND token = 'MGrxHMSVY0glCbTvBGBdt+O3eDHLn/LU2HZqu5FF4S8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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